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instruction manual for transformer differential

1. 22 eee COMS 25 1 PADDLE D 490 e See COM 2 2 28 1 BARS GSE SER 4 iam L 25 451 w Y YX POWER SUPPLY STATUS m 9 ray AA A L9 3 7 ee Own s E GROUND AAAS 4 TERMINAL INTERNAL V CIRCUITRY e TARGET TARGET POWER E zA S U PP LY UNRES RES TRIP TRIP e MEJEJE 10 8 6 4 2 P0012 31 05 29 02 Figure 4 12 Internal Connections Three Phase Two Input Sensing Input Type E Output Option E 9171300990 Rev R BE1 87T Installation 4 13 SUPPLY STATUS EXTERNAL CASE GROUND TERMINAL PADDLE OPERATED SHORTING BARS BE1 87T D983 025 2 18 93 Figure 4 13 Internal Connections Three Phase Two Input Sensing Input Type E Output Option F 4 14 BE1 87T Installation 9171300990 Rev R PADDLE OPERATED SHORTING BARS SUPPLY STATUS EXTERNAL CASE GROUND TERMINAL BE1 87T D983 023 2 18 93 UNREST REST Bet 87T S71 9 19 POWER TARGET TARGET A OPTIONAL OPTIONAL gt J d 877 87T 5 20 RESTRAINED LEGEND 87T 87T TRANSFORMER DIFFERENTIAL RELAY 86 LOCKOUT RELAY A OPTIONAL CURRENT OPERATED TARGETS AUXILIARY OUTPUT OPTION FOR SINGLE PHASE NO
2. H X C C B i H B H t A 1 4 H Switch BE1 87T board 18 terminal 16 WYE blocks 15 13 14 12 141 11 4 D2751 23 03 12 98 Phase shift jumper position on analog board 2 Figure 4 29 Three Phase Connections Wye Delta Configuration Internal Phase Compensation The transformer in the example shown in Figure 4 29 has a delta connection on the secondary winding The currents in each winding of the delta are A B and C respectively as reflected from the wye connected primary winding The delta connection of the transformer windings causes the current flowing in the phase leads connected to the delta winding to be A C B A and C B respectively The CT currents on the wye side must be combined similarly to provide A C B A and C B to compensate This is shown in Figure 4 27 by selecting phase compensation jumper position A1 for the wye side input 4 28 BE1 87T Installation 9171300990 Rev R H 3 PC ott X si lt ie ile B H Br E B 3 Bills 316 H X 1 n 1 A pile 5116 Er mie i Switch 7 board 18 terminal m 16 blocks 15 13 14 12 np D2751 24 Phase shift jumper _ V ABS H X position on analog board 2 Figure 4 30 Three Phase Connections Delta Delta Configuration 91713
3. in pu OR Ex gt gt slp Ti ore 100 100 the value of 12 trip max is defined as h trip balance pu l T OR 1 19 100 Ti 2 When 0 35 balance lt in pu 100 the maximum trip point is established as 12 trip 7 balance 0 35 in pu 1 I2trip max 035 1 Example Three Assume tap 2 tap 3 8 slope 15 Inputs 7 22 A 1 pu 1 3 8 A 1 pu 9171300990 Rev R BE1 87T Test Procedures Equation 3 Equation 3a Equation 4 Equation 4a 5 5 Check 0 35 Iobalance gt slope 1 lt 2 333 Therefore Use Equation 4 or 4a From Figure 1 2 the percentage restraint characteristic of the BE1 87T at 15 slope the minimum current where trip occurs is Ip trip 1 pu 0 35 0 65 pu In terms of current the trip current is I5 trip 0 65 pu Tap 0 65 3 8 2 47 6 100 mA 2 Using Equation 4a I2trip 2 035 247A Example Four Assume tap 2 tap 3 8 slope 15 Inputs 6 A 3 pu I 11 4A 3 pu Check 0 35 balance lt gt pu 100 Bas ve 0 35 0 15 3 2 333 Therefore Use Equation 3 or 3a From Figure 1 2 the percentage restraint characteristic of the BE1 87T at 1596 slope the minimum current where trip occurs is 3pu 1 0 15 2 55 pu 12 In terms of current the trip current is I5 trip 2
4. 1 2 00222 20 000 00 000610 a 1 4 Style Number 4 l U U 1 4 SPEGIFIGATIONS enter ed au 1 5 Current Sensing 1 1 5 Current Sensing Burden n n snn 1 5 Tap Setting Control Scaling 1 5 Restrained Outputs re err eicere dese 1 5 Front Panel Setting aee aer Re 1 6 Unrestrained OUtpUL tre e iPad dd rere e P eh Ue Pee epe 1 6 aarti iet 1 7 2 2 tendunt tante tanus 1 7 1 7 Moe e LEE 1 7 Sola iON us otc edet a 1 9 Power Supply eer 1 9 Surge Withstand Capabillfyi y L u uu G itu qa uaqta en nennen rnit 1 9 Radio Frequency Interference RF I l Q s a 1 9 WIE RECOGNITION s L eat eeu cea ecu pal scm nai deca natn eee 1 9 GOST R Certificato Nesie 1 ette eoim ME Dee m EE CLER S Un meme 1 9 enin te i edt Satu Ria eset es 1 9 SHOCKS cee CRT Pere Dt tu a MM LL I E 1 9 VIDE
5. H B e o o J H X AYA o A i id X T Lo o SWITCH BOARD TERMINAL BOARDS BE1 87T 1 B 2 12 aja 14 h A9 A BE1 87T 1 ga 2 12 a 14 AQ BE1 87T 1 e 2 12 11 1 3 14 v N D1186 04 H X 03 12 98 BE1 87T B TYPE SENSING Figure 4 26 Single Phase Connections Delta Wye Configuration With Two Load Busses Three Phase Input Sensing Connections Phase Shift Compensation Three phase units must be connected in a way that will negate any phase shift introduced by the protected power transformer This is accomplished by one of two methods 1 By connecting the system CTs to complement the power transformer connections i e a wye delta CT can negate the phase shift of a delta wye power transformer and vice versa 2 By utilizing the internal 30 Phase Shift Compensation that is a feature of three phase BE1 87T relays Advantages of Internal Phase Compensation Three phase units provide for internal phase angle compensation Among the advantages of this method is the ability to connect all the CTs in wye This not only simplifies the connections but also facilitates sharing the CTs with other devices Furthermore the wye connection reduces the burden on the CTs A set of movable jumpers Figure 4 27 determines the direction of the compensating internal phase shift for each input Because eac
6. 1304 3 HIGH TERTIARY LOW 2863 Ip 2 3563 IE 6 0 2 0 E 2 5 524 zb 524 Step 18 Determine the unrestrained pickup level in multiples of tap X TAP Refer to Appendix A Setting Note 4 X TAP 0 7 Ig Max HIGH TERTIARY LOW Ij not maximum 1 maximum X TAP 0 7 24 16 8 Note The restrained element will not operate due to the large 2nd harmonic component present in the highly distorted current Step 19 Using the results of Step 18 set the UNRESTRAINED PICKUP LEVEL control Referring to the table on the BE1 87T front panel select the tap position X TAP that is higher than the result obtained in Step 18 Therefore for this example select SET position P 19 X TAP which is higher than the above result of 18 2 A Slope Setting Step 20 Determine the multiples of self cooled current 7 Refer to Appendix A Setting Note 5 _ IR MVASELF COOLED T MVAFORCED COOLED Where In relay current from Step 4 T the input tap from Step 9 MVA SELF COOLED and MVA FORCED COOLED are given in Figure 4 33 9171300990 Rev R BE1 87T Installation 4 39 Step 21 4 40 HIGH TERTIARY LOW iE 6 04 Q00 r 169040 1 05900 2 0 250 6 0 50 2 5 250 2 42 2 24 2 42 Select the restrained slope setting The recommended restrained slope setting S is a function of the total mismatch and the power transformer exciting current This provides an ample security
7. E steaks cules 4 1 RELAY OPERATING PRECAUTION S Ring er tne deed tt beds 4 1 eye 4 1 DIELECTRIC TEST uiii itta et iba usai eee e rdg cet ode dan 4 9 5 etico ia ecrit eR ie te te edle ete E 4 9 RELAY DISASSENMBLY iu er rt e eat ee ale reni io 4 17 PIOCAUTIONS EET 4 17 Circuit Board Removal Procedure entrent nnns 4 17 DISABLING 4 18 Single Phase Units dad Era Linie FORE tr rapa 4 20 Three Phase Units L 4 20 SENSING CONNECTION 7 4 20 Single Phase Input Sensing Connections L u 4 20 Three Phase Input Sensing 4 20 SETTING THEBEN 8 a eoa teret sae anu vst date Pasa DOR eve eap edu e ea adus 4 33 Iso TELE 4 33 Procedure One o rite n ie ce eI i tete tne ra pierre Retos tk RA Lane 4 33 Procedure TAO M 4 42 CHECKING THE RELAY SETTINGS AND SYSTEM INPUTS seen 4 49 MAINTENAN GE 2 2 eit eec Eee dete pea is nte abet d eR RR LER 4 50 SORA GE dedit b susunan aie tede
8. VCE 800 200 533 3 Step 16 Determine the saturation factor Sp VB is the largest of the burden voltages calculated in steps 13 and 14 Vg SF VCE HIGH LOW Sr 22 4 Sr 98 0 200 533 3 0 11 0 18 NOTE Maximum Recommended S 0 5 Larger saturation factors will make the relay insecure for external faults The only solution is to increase the CT quality Instantaneous Unrestraint Unit Setting Step 17 Determine the maximum external fault multiple g For wye connected CTs and with WYE jumpers on Analog Board 2 shown in Figure 2 4 Ir Maximum Relay Fault Current Corresponding 4 46 BE1 87T Installation 9171300990 Rev R For delta connected CTs or with 1 or 2 jumpers on Analog Board 2 shown in Figure 2 4 and based on phase to phase fault See Setting Note 3 18643 fps HIGH LOW 32 66 43 I SS oe E730 IgE 2 15 96 E Step 18 Determine the unrestrained pickup level in multiples of tap X TAP See Setting Note 4 X TAP 0 7XIg Max HIGH LOW X TAP 0 7 15 96 Ig not maximum 11 17 This calculation assumes that the CTs carrying the maximum fault saturate severely yielding only 30 of the expected ratio current This leaves 70 of the fault current as a false differential current NOTE The restrained element will not operate due to the large 2nd harmonic component present in the highly distorted current Step 19 Using the resul
9. RESTRAINED ye oA C RESTRAINED is UNRESTRAINED INPUT 1 OUTPUTS COM M FK oA POWER SUPPLY STATUS CONTACTS INPUT 2 4 gC com P0012 32 05 30 02 Figure 4 9 Case Terminals Three Phase Two Input Sensing Input Type E Output Option F 4 10 BE1 87T Installation 9171300990 Rev R BET 87T POWER INPUT 1 2 RESTRAINED COM COM OUTPUTS UNRESTRAINED POWER SUPPLY STATUS CONTACTS 9 INPUT 2 COM on INPUT 3 4 gC P0012 33 05 30 02 Figure 4 10 Case Terminals Three Phase Three Input Sensing Input Type G Output Option E 9171300990 Rev R BE1 87T Installation 4 11 INPUT 4 CO 1 PADDLE E OPERATED 17 15 13 C1 SHORTING NPUT 5 INPUT 3 NPUT 2 BARS 20 16 14 12 X gt x Ny YY p POWER SUPPLY VA AA f STATUS EREN A rn N e EXTERNAL CASE GROUND M I TERMINAL INTERNAL CIRCUITRY POWER TARGET TARGET AUX SUPP a UNREST REST TRIP TRIP AN e 9 5 COM AUX AUX 10 com P0012 30 UNREST RES AUX COM 3 05 29 02 Figure 4 11 Internal Connections Single Phase Five Input Sensing Input Type D Output Option E 4 12 BE1 87T Installation 9171300990 Rev R
10. Target Reset Switch Resets the electronically latched targets Auxiliary Relay Control Two internal slide switches 61 and S2 enable the Switches Option optional Auxiliary Output Relay to close only when a restrained output occurs S1 ON only when an unrestrained output occurs S2 ON or to close when either output occurs S1 and S2 ON When shipped from the factory the Auxiliary Relay will be configured with S1 and S2 ON NOTE The switches are located on the mother board and are only accessible by withdrawing the relay case ELEMENT Targets Option Electronically latching LED targets indicate the phase three phase units ONLY that caused a trip operation RESTRAINED PICKUP Thumb wheel switches one per phase element are LEVEL Switches used to adjust the desired percent of allowable through current restraint from 15 to 60 96 in 5 96 increments Through current is the greatest relative individual input current The through current restraint characteristic is individually adjustable for phases A B and C In a three phase unit all three switches are typically kept at identical settings UNREST TRIP Indicator Red LED lights when there is an unrestrained pickup E REST TRIP Indicator Red LED lights when there is a restrained pickup M Indicator Red LED lights when the OF TRIP pushbutton P is pressed and the restraint current is below the slope characteristic kneepoint as defined in Table 1 1 That is the relay wi
11. 27 are in the WYE WYE position Relays are shipped with all jumpers in this position If one of the inputs requires a shift in phase the jumpers for all three phases are moved as follows 1 The A2 position develops A B B C C A 2 The A1 position develops A C B A C B NOTE The result of each of these vector differences has a magnitude of the square root of three times each component The internal phase shift compensation is performed electronically as shown in the chart of Figure 4 27 The internal compensation can apply to any power transformer with any combination of wye delta or autotransformer winding connections A procedure to check the differential balance is described later in this section CHECKING THE RELAY SETTINGS AND SYSTEM INPUTS 9171300990 Rev R BE1 87T Installation 4 25 gt gt lA 1 TAD 1 1 2 CompensatedI magnitude is J3x 30 I 30 Compensated magnitude D638 002 03 12 98 I A1 Compensation for A Phase I Ic A1 A2 Compensation for A Phase Figure 4 27 30 Phase Shift Compensation Jumpers The transformer in the example shown in Figure 4 28a and 4 28b has a delta connection on the primary winding The currents in each winding of the delta are A B and C respectively as reflected from the wye connected secondary winding The delta connection of the transformer windings causes the current flowing in the phase leads connected to the delta winding to be A B
12. MOTHERBOARD MOTHERBOARD FRONT PANEL 5636 003 THREE PHASE 2 23 93 Figure 4 19 Side View of Cradle Assembly DISABLING UNUSED INPUTS To eliminate the possibility of a spurious input from induced currents within the relay special internal jumpers have been provided to disable any inputs that are not connected to CT wires CAUTION Disabling unused inputs requires disassembly of the relay and must be done when the relay has been taken out of service Access to the input disabling jumpers requires the removal of the Analog 1 Board shown in Figure 4 19 To avoid personal injury or equipment damage do NOT proceed unless thoroughly familiar with the instructions in sections RELAY OPERATING PRECAUTIONS and RELAY DISASSEMBLY Precautions 4 18 BE1 87T Installation 9171300990 Rev R NOTE FOR ALL 2 INPUT RELAYS BOTH SINGLE AND THREE PHASE ALL JUMPERS MUST BE IN THE DISABLE POSITION AT ALL TIMES FOR OTHER RELAYS SEE CHART BELOW x E RIGHT HAND EDGE OF ANALOG BOARD 1 LOOKING FROM FRONT OF RELAY anaes 9 21 94 374 172 NW AE Figure 4 20 Unused Input Disabling Jumpers Analog 1 Board Option 1 0 FACTORY J9 NOT FIELD ADJUSTMENT ADJUSTABLE BE1 87T D1924 12 9 21 94 foo oy WP e at Figure 4 21 Unused Input Disabling Jumpers Analog 1 Board Option 1 1 9171300990 Rev R BE1 87T Installation Single Phase Units Single Phase Units wi
13. Serial No XXXXXXXXXXXX PUSH TO ENERGIZE See Fig 2 4 QUTPUT A B C R U ELEMENT L FUNCTION U S PATENT 5 014 153 PATENTED IN CANADA 1993 P0052 24 Figure 2 1 Sensing Input Range 1 or 3 Three Phase Three Inputs 2 4 BE1 87T Controls and Indicators 9171300990 Rev R ES Basler Electric INPUT 1 INPUT 2 INPUT 3 INPUT 4 INPUT 5 1 00 1 60 1 00 1 60 1 00 1 60 1 00 1 60 1 00 1 60 REST UNREST TRIP TRIP RESTRAINED PICKUP LEVEL amp o o ma cf of ef of o D L THRU CURRENT 15 20 25 30 35 40 45 sof 55 60 1 87 lt K TRANSFORMER DIFFERENTIAL POWER WAY Style No D4E A1J DOS5F Serial No XXXXXXXXXXXX PUSH TO ENERGIZE OUTPUT See Fig 2 4 R UC io E FUNCTION U S PATENT 5 014 153 PATENTED IN CANADA 1993 P0052 23 Figure 2 2 Sensing Input Range 1 or 3 Single Phase Five Inputs 9171300990 Rev R BE1 87T Controls and Indicators See Fig 2 4 ES Basler Electric INPUT 2 100 1 60 C yv UNREST TRIP PHASE A THRU UNREST TRIP UNREST L TRIP PHASE C TRANSFORMER DIFFERENTIAL WAY Style No E2E A1J DOSOF Serial No XXXXXXXXXXXX See Fig 2 4 P0052 25 ELEMENT h CURRENT D See Fig 2 4 POWER PUSH TO ENERGIZE OUTPUT R uO L eunction
14. Step 1 Step 2 Step 3 Connect Input 1 current to terminals A and N Connect Input 2 current to terminals A and N This verifies the A and C phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The B phase differential circuit sees no current and does not respond Connect Input 1 current to terminals B and N Connect Input 2 current to terminals B and N This verifies the A and B phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The C phase differential circuit sees no current and does not respond Connect Input 1 current to terminals C and N Connect Input 2 current to terminals C and N This verifies the B and C phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The A phase differential circuit sees no current and does not respond Jumper Positions A1 A2 Step 1 Step 2 Step 3 Connect Input 1 current to terminals A and N Connect Input 2 current to terminals N and B This verifies the A and B phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The C phase differential circuit sees no current and do
15. The unit is designed to operate from the secondary of current transformers rated at either 1 Aor 5A Frequency range is 5 Hz of nominal 4 Acontinuous 50 A or 50 X tap whichever is less for 1 second 20 Acontinuous 250 A or 50 X tap whichever is less for 1 second For ratings other than one second the rating may be calculated as me t Where tis the time in seconds that the current flows K 50 Aor 50 X tap whichever is less 1 Amp CT Units or K 250 Aor 50 X tap whichever is less 5 Amp CT Models Less than 0 02 ohm per phase Front panel rotary switches labeled INPUT permit scaling the sensed input current or tap setting over the range of 0 4t01 78in0 02A increments 2 01t108 9A in0 1Aincrements Front panel thumbwheel switches adjust pickup of the restrained output as a percentage of the through current The range is 15 to 60 of the operating current in 5 96 increments 6 96 of pickup 100 mA 5 Ampere Units or 20 mA 1 Ampere units 0 35 6 of tap setting Refer to Table 1 1 and Figure 1 2 Table 1 1 provides calculated intersection points of the slope characteristic and the minimum pickup in multiples of tap as shown in Figure 1 2 The calculation was derived from the formula Minimum Pickup Maximum I Restraint estrain percent of Slope For example Minimum Pickup _ 0 35 Percent of Slope 20 The relay operates when the per unit difference current operating current is above
16. A 10 9171300990 Rev R BE1 87T Introduction ix This page intentionally left blank BE1 87T Introduction 9171300990 Rev R SECTION 1 GENERAL INFORMATION INTRODUCTION These instructions provide information concerning the operation and installation of BE1 87T Transformer Differential Relays To accomplish this the following is provided Specifications Functional characteristics Mounting information e e e e Setting procedures and examples WARNING To avoid personal injury or equipment damage only qualified personnel should perform the procedures presented in these instructions These instructions may be used in place of all earlier editions For change information see Section 8 NOTE FOR USERS OF SENSING INPUT TYPE F RELAYS Users of BE1 87T relays with Sensing Input Type F three phases three inputs per phase will find Difference Data in Section 6 of this manual that describes features specific to these relays The three phase three inputs per phase design previously available as Sensing Input Type F has been modified and is now available as Sensing Input Type G Due to differences in components and output terminal connections Type G relays are not compatible with earlier versions of the BE1 87T with Sensing Input Type F There are also differences in the output connections as described in Section 6 Difference Data DESCRIPTION BE1 87T Transformer Differential Relays provide primary prote
17. Application Example Autotransformer With Tertiary Winding See Figure 4 32 for 3 phase connections SPECIFICATIONS HIGH SIDE TERTIARY LOW SIDE CT Ratio 600 5 2000 5 um 600 5 T 1200 5 CT Accuracy Class C400 One Way Lead Burden ohms 0 7 CT Connection Three Phase WYE WY WYE NOTE Three phase is the most common application of the BE1 87T Using single phase relays requires a Delta connection for the High side and Low side CTs to match the tertiary connection in the example detailed in Figure 4 32 Step 3 Units Only Adjust the phase compensation jumpers on Analog Board 2 shown in Figure 2 4 and Figure 4 27 or use the procedure listed in TESTING THREE PHASE UNITS WITHOUT CHANGING JUMPERS in Section 5 Because of the grounded winding in this example as shown in Figure 4 33 and 4 32 the high side and low side zero sequence currents must be canceled A2 position is selected to align the High side and Low side secondary current phasors with the tertiary phasors which lead by 30 in this example HIGH TERTIARY LOW Jumper A2 WYE A2 Position 9171300990 Rev R BE1 87T Installation 4 35 Step 4 Determine the relay current lp Ig Ig Conversion Factor Three Phase Units only When using either A2 or A1 jumper positions shown in Figure 2 4 multiply the secondary current 7 by the conversion factor square root of three just as if the CTs were connect
18. Maintenance to Section 4 Installation e Added GOST R certification to Section 1 General Information Q 10 05 e In Section 1 General Information Specifications corrected values for Maximum Current per Input for 1 Ampere CT Units e n Section 5 Test Procedures corrected values inside CAUTION box for 1 AMP CT on page 5 14 P 05 03 e Added a thumbscrew to the figure on the manual front cover e Added not all styles to the Power Supply Output heading on page 3 4 as well as added NOTE and a text box around the second last paragraph on page 3 4 e Added the new thumbscrew to Figure 4 1 and changed the height dimensions in Figure 4 2 e Clarified the terminal numbers on Figure 4 6b e Added a shorting bar between terminals 6 amp 7 in Figure 4 11 e Added a shorting bar and normally open contact and normally closed contact effecting terminals 1 2 amp 5 in Figure 4 12 e Step 13 was corrected on pages 4 31 and 4 39 to include Ry in the formulas e Values were changed to Table 5 4 under Option 1 0 for Unrestrained Trip N 09 00 e Corrected Table 1 3 to show power supply ranges e Changed instruction manual front cover Figures 4 1 4 3 and 4 5 to show new unit case covers e Changed Figure 4 32 per markup M 04 99 e Table 3 1 changed mid range nominal volt 125 Vac to 120 Vac e Corrected Figures 4 24 4 31a and A 3 e Corrected page 4 38 Step 10 added note to page 4 39 Step 13 and corrected Steps 14
19. Step 8 5 14 Relays without Changing Jumpers at the end of this section Replace all circuit boards and reassemble the relay Refer to Table 1 1 and Figure 1 2 for multiples of tap and percentage restraint characteristics Set the RESTRAINED PICKUP LEVEL switches and the INPUT 1 and INPUT 2 tap switches to the values shown in Table 5 5 Apply power to the relay Apply input current as indicated in Table 5 5 for each input Then reduce the Input 2 current or increase the Input 1 current until the REST TRIP LED lights This should occur as the input current being adjusted reaches the level given in the Trip Amperes column for the respective input If the relay has more than two inputs reconnect the relay by substituting the Input 3 terminals for the Input 2 terminals Then repeat step 6 and 7 using the Input 2 values of Table 5 5 for Input 3 If there are more than three inputs as in some single phase units continue substituting every higher numbered input for Input 2 each time comparing the input under test against Input 1 as in Steps 6 and 7 BE1 87T Test Procedures 9171300990 Rev R Step 9 Three Phase Units Only Repeat Steps 6 7 and 8 for phases B and C Refer to Figures 5 2 through 5 5 as appropriate for the terminal numbers of the phase B and C inputs of the relay under test Table 5 5 Restraint Pickup Test 1 A 50 or 60 Hz 15 15 15 15 2 2 2 2 5 5 5 5 3 3 O O CO RP
20. The trip time should be less than that shown in Table 5 4 Three Phase Units Only Repeat Steps 1 through 5 for Phases B and C Place the UNRESTRAINED PICKUP LEVEL switch to the A setting 6 X TAP Place all of the INPUT switches to the 2 0 A tap position With 0 0 A at Input 1 terminals 11 amp 13 apply 24 A 2 x Pickup to Input 2 terminals 12 and 13 on single phase and terminals 15 amp 18 on three phase Note the time interval between initiation of the simulated fault and the closure of the unrestrained output contact The interval should be less than that shown in Table 5 4 Repeat Steps 7 and 8 at 10 x Pickup Note that with Input 1 at 0 0 A it will be necessary to step the Input 2 current to 120 0 A for an unrestrained trip The trip time should be less than that shown in Table 5 4 Three Phase Units Only Repeat Steps 8 and 9 for phases B and C Table 5 4 Timing 5 A 50 or 60 Hz Option 1 0 Option 1 1 Timing Maximum Timing Maximum Function Differential Current 50Hz 60Hz 50 or 60 Hz Restrained Trip 49 ms Restrained Trip 37 ms Unrestrained Trip 57 ms Unrestrained Trip 10 x Pickup 32 ms 28 ms 10 ms 9171300990 Rev R BE1 87T Test Procedures 5 13 VERIFICATION TESTS 1 AMP CT 50 OR 60 HZ UNITS CAUTION Current supplied to the BE1 87T input terminals must not exceed 4 A continuous or 50 A for 1 second Whenever 4 A must be exceeded provisions must be made to cut off the sensing
21. When the Target option is specified as either C or D shown in the seventh position of the Style Number electronically latched indicators labeled FUNCTION are incorporated in the front panel The electronically latched and reset targets consist of red LED indicators The appropriate target is tripped when either a restrained R or unrestrained U output occurs Latched targets are reset by operating the target reset switch on the front panel If relay operating power is lost any illuminated latched targets are extinguished When relay operating power is restored the previously latched targets are restored to their latched state When targets are specified for three phase relays three additional ELEMENT targets are incorporated to indicate the phase involved Only the FUNCTION targets restrained R or unrestrained U are available for single phase units Relays can be equipped with either internally operated targets Type C or current operated targets Type D Both target types are reset by operating the target reset switch e Type target referred to as internally operated is actuated by an integral driver circuit that responds directly to the relay internal logic This type of target is tripped regardless of the amount of current flowing through the associated output contact e Type D target referred to as current operated is actuated when a minimum of 0 2 A flows through the associated output contacts To accomplish this a spe
22. Xo OR H X BUSHING 151A t A1 OR A2 AS APPROPRIATE 18 N 1 terminal 14 C blocks 12 B 141 OR A2 13 N D2751 26 03 12 98 Phase shift jumper position on analog board 2 NOTES THE BE1 87T MUST USE THE SAME PHASE COMPENSATION JUMPER POSITION ON ALL INPUTS Figure 4 31b Three Phase Connections Wye Wye or Autotransformer Configuration Internal Phase Compensation 9171300990 Rev R BE1 87T Installation 4 31 X C x B X P H 3 2 H B Y B lt H Y A 1 d 1 A MN TR 5 Switch board in terminal dis ji blocks I L 14 12 11 13 2 5 6 7 18 15 16 17 Lo w BE1 87T J lt A A2 WYE A2 D2751 27 vsd 09 07 00 A Figure 4 32 Three Phase Connections Autotransformer With Loaded Delta Tertiary The transformer in the example shown in Figure 4 32 has a delta connection on the tertiary winding The currents in each winding of the delta are A B and C respectively as reflected from the wye or auto connected winding The delta connection of the transformer windings causes the current flowing in the phase leads connected to the delta winding to be A B B C and C A respectively The CT currents on the wye or auto windings must be combined similarly to provide A B B C and C A to compensat
23. 05 28 02 Inches Millimeters Figure 4 1 Outline Dimensions Front View BE1 87T Installation 9171300990 Rev R 5 56 141 3 5 56 141 3 00000 00000 20 Oh GO e eO 2 9 e 000000 00000 20 9171300990 Rev R PROJECTION MOUNTING SEMI FLUSH MOUNTING Inches Millimeters Figure 4 2 Outline Dimensions Rear View BE1 87T Installation 4 3 22 S lt A 2 EN Inches Millimeters Figure 4 3 Outline Dimensions Side View Semi Flush Mounting 4 4 BE1 87T Installation 9171300990 Rev R 9171300990 Rev R Inches Millimeters Figure 4 4 Panel Drilling Diagram Semi Flush Mounting BE1 87T Installation 4 5 l N I Inches Millimeters Figure 4 5 Outline Dimensions Side View Projection Mounting 4 6 BE1 87T Installation 9171300990 Rev R 7 41 188 1 6 20 157 6 D1427 12 a NOTES 01 16 98 N OPTIONAL RECTANGULAR CUTOUT MAY REPLACE 10 DRILLED HOLES 2 TERMINAL NUMBERS SHOWN ARE AS VIEWED FROM REAR OF RELAY 3 BOTTOM HALF OF PANEL DRILLING DIAGRAM FROM CENTERLINE DOWN IS SHOWN IN FIGURE 4 6b Inches Millimeters Figure 4 6a Panel Drilling Diagram Top Half Projection Mounting 9171300990 Rev R BE1 87T Installation 4 7
24. 55 pu Tap 2 55 3 8 9 69 A 6 100 mA 5 6 BE1 87T Test Procedures 9171300990 Rev R I2trip 1 0 15 x 6 x 9 69 A Using Equation 3a NOTE The relay operates on maximum restraint By reducing the current of one input the published trip non trip regions are as defined by Figure 1 2 TEST SETUP DIAGRAMS Refer to the appropriate test setup diagram under Related Topics Figure 5 2 Test Setup Single Phase Figure 5 3 Test Setup Three Phase Sensing Input Type E Output Option E 9171300990 Rev R BE1 87T Test Procedures 5 7 Figure 5 4 Test Setup Three Phase Sensing Input Type E Output Option F Figure 5 5 Test Setup Three Phase Sensing Input Type G Output Option E 5 8 BE1 87T Test Procedures 9171300990 Rev R VERIFICATION TESTS 5 AMP CT 50 OR 60 HZ UNITS CAUTION Current supplied to the BE1 87T input terminals must not exceed 20 A continuous or 250 A for 1 second Whenever 20 A must be exceeded provisions must be made to cut off the sensing current automatically after a suitable time interval Sensing current can be calculated by using the following equation K IE Jr Where K 250 or 50 x tap whichever is less t the time in seconds that the current flows Restrained Pickup Verification Step 1 Step 2 Step 3 Step 4 Connect the relay as appropriate refer to Figures 5 2 through 5 5 beginning with input terminals 11 and 13 for the initial t
25. B C and C A respectively The CT currents on the wye side must be combined similarly to provide A B B C and C A to compensate This is done in Figure 4 28a by connecting the wye side CTs in delta such that the currents sent to the relay are A B B C and C A This is shown in Figure 4 28b by selecting phase compensation jumper position A2 for the wye side input 4 26 BE1 87T Installation 9171300990 Rev R ALA V ALA Switch board terminal blocks CAAK D2751 21 03 12 98 Phase shift jumper position on analog board 2 An alternative to grounding one corner of the delta connected CTs is to connect the ground to a lead connected to terminal 18 Figure 4 28a Three Phase Connections Delta Wye Configuration CT Compensation Y VY V NP WP NP CYN YN Switch board terminal blocks CYN YA 18 17 16 15 13 14 12 11 02751 22 02 05 98 Phase shift jumper position on analog board 2 Figure 4 28b Three Phase Connections Delta Wye Configuration Internal Phase Compensation 9171300990 Rev R BE1 87T Installation 4 27
26. Hz Units Range 3 One Ampere CT 60 Hz Units Range 4 and One Ampere CT 50 Hz Units Range 2 Within each group are separate tests that can be performed individually to make it easier to focus on a particular problem However all of these tests should be performed prior to putting the relay into service To help field users understand the verification procedures four examples for restrained pickup testing are provided before the actual Verification Tests begin Two examples are for increasing one input from balance and two examples are for decreasing one input from balance These examples are not a necessary part of verification testing but are provided for clarification For routine assurance that the BE1 87T is operating correctly the simplified OPERATIONAL TESTS may be performed Before starting a test program check the Style Number of the relay against the Style Number Identification Chart Figure 1 1 to identify the specific features and options to be tested For location of the switches and controls refer to Figures 2 1 and 2 2 for Input Range 1 or 3 and Figures 2 3 and 2 4 for Input Range 2 or 4 NOTE LEDs and targets if provided should be checked for proper operation and targets reset after they have been tripped Current operated Type D targets will only operate when a minimum of 0 2 A is present in the trip circuit Similarly the auxiliary contacts if present should be checked for proper operation Switches S1 and
27. NC OR SPDT BE1 87T D240 008 4 21 94 Figure 4 15 Control Circuits Single Phase Output Option E 9171300990 Rev R BE1 87T Installation 4 15 87T 19 POWER TARGET SUPPLY OPTIONAL A STATUS 720 87T RESTRAINED LEGEND 87T 87T TRANSFORMER DIFFERENTIAL RELAY 86 LOCKOUT RELAY N OPTIONAL CURRENT OPERATED TARGETS AUXILIARY OUTPUT OPTION FOR SINGLE PHASE NO NC OR SPDT BE1 87T D240 015 4 21 94 Figure 4 16 Control Circuits Three Phase Two Input Sensing Input E Output Option E 87T 877 9 TARGET o 877 TARGET 19 OPTIONAL A OPTIONAL STATUS 87T 87T 87T 87T 6 877 RESTRAINED 7 RESTRAINED T RESTRAINED T UNRESTRAINED 20 PHASE A PHASE B PHASE C 87T 1 2 8 10 LEGEND 87T 87T TRANSFORMER POWER DIFFERENTIAL RELAY 86 LOCKOUT RELAY 87T BE1 87T 3 OPTIONAL CURRENT 9 OPERATED LT TARGETS Figure 4 17 Control Circuits Three Phase Two Input Sensing Input E Output Option F 4 16 BE1 87T Installation 9171300990 Rev R Figure 4 18 Control Circuits Three Phase Three Input Sensing Input Output E RELAY DISASSEMBLY Precautions The following procedures require the removal and handling of the internal printed circuit boards Figure 4 19 shows the location of major components and assemblies Because some of the components are vulnerable to electrostatic charge the following precautions
28. O O C OPR O O aja 4 5 5 ajo Input 1 Tap 2 0 Input 2 Tap 3 8 Increasing Input 1 Decreasing Input 2 1 2 3 2 28 3 2 667 0 180 1 026 0 082 Input or Tap Switch Verification Each input is scaled using a combination of two rotary switches Verify the switches as follows Step 1 Step 2 Step 3 Determine the Sensing Input Type the first digit of the Style Number shown on the front panel Single phase two inputs Single phase three inputs Single phase four inputs Single phase five inputs Three phase two inputs each phase G Three phase three inputs each phase Connect the input being tested to the current source as shown the appropriate diagram Figures 5 2 through 5 5 Set the INPUT under test to the 0 78 tap position as shown in Table 5 6 Set the RESTRAINED PICKUP LEVEL switch to position A 15 Apply current to the input under test increasing the current until the REST TRIP LED lights At this point the input current should be 0 273 A 6 20 mA 9171300990 Rev R BE1 87T Test Procedures 5 15 Step 4 Repeat Step 3 for the additional tap positions shown in Table 5 6 This verifies the accuracy of all the binary combinations of the rotary switches Step 5 Test the other inputs by reconnecting to the next pair of terminals for your relay and repeating Steps 3 and 4 The successful completion of these tests will verify the electrical integrity of a
29. and 16 e Page A 2 changed 3 Phase fault ratio current to 3 phase fault current e Page A 3 corrected formulas for Figure A 3 e Under Section 4 Procedure One Verify CT Performance changed the procedure to the ANSI accuracy class method This forced changes in the following steps 12 13 14 16 18 20 and 21 e Under Section 4 Procedure Two Verify CT Performance changed the procedure to the ANSI accuracy class method This forced changes in the following steps 12 13 14 and 16 e Added ECO revision information to Table 8 1 Added Setting Note 7 ANSI Accuracy Class Method to Appendix A L 05 97 e delete the part number from the front cover of the manual 9171300990 Rev R BE1 87T Introduction iii Manual Revision and Date Change K 03 97 Deleted all references to Service Manual 9171300620 Changed the Title of Section 2 from Controls and Indicators to Human Machine Interface Replaced the Power Supply Options paragraphs with a new Power Supply paragraph explaining the new power supply design Deleted Figure 3 2 and added Table 3 1 Wide Range Power Supply Voltage Ranges Changed Power Supply Status Output for Type G power supply on the formerly page 3 6 now page 3 4 from terminals 9 and 20 to terminals 9 and 19 Added information to Section 4 to help the user understand the procedures better Deleted all NOTES FOR USERS OF SENSING INPUT TYPE F RELAYS and added
30. desired pickup LEVEL Switches setting for all phases of the unrestrained output The adjustment range is from 6 to 21 times the phase tap setting in increments of 1 CALIBRATE Switch A two position switch is located on each Analog 1 three phase units ONLY Board and is easily accessible on the right side of the relay when it is withdrawn from the case In the CALIBRATE position these switches inhibit the harmonic share feature when calibrating the 2nd Harmonic Restraint In the NORMAL position the relay will operate normally 30 Phase Shift Jumpers These jumpers control the internal phase shift of the POWER Indicator This LED will illuminate when operating power is supplied to the internal circuitry of the relay 9171300990 Rev R BE1 87T Controls and Indicators 2 1 PUSH TO ENERGIZE Two momentary pushbutton switches are accessible by OUTPUT Switches Option inserting a 1 8 inch diameter non conducting rod through access holes in the front panel Switch R when actuated closes the Restrained Output Relay contacts Switch U when actuated closes the Unrestrained Output Relay contact s NOTE The optional Auxiliary Relay contacts Option 3 1 3 2 or 3 5 will also be operated by the PUSH TO ENERGIZE switches if enabled by the two internal Auxiliary Relay Control Switches Refer to LETTER FUNCTION Targets Option Electronically latched LED targets that indicate an unrestrained or restrained output has occurred
31. es at uta Fate tke pasasqa 4 50 FEST Ju cp EET ER 4 50 SECTION 5 e TEST PROCEDURES irre neri teer ined dn u u u 5 1 OVERVIEW mL 5 1 EQUIPMENT REQUIRED aieiaa iei ave dei duse tg 5 1 MUNERE 5 1 RESTRAINED PICKUP TESTING EXAMPLES sess a 5 2 Increasing One Input from 1 00 L nennen nnns nennen nnns 5 2 Decreasing One Input from 2 2 4 0 0000000 eene enne 5 5 TEST SETUP BIAGRAMS tuii diee id ae av ee Ma dc d n deg ut 5 7 VERIFICATION TESTS 5 AMP CT 50 OR 60 HZ UNITS entren 5 9 Restrained Pickup Level Verification ua 5 9 Input or Tap Switch I n n 5 10 Unrestrained Pickup Verification U U 5 11 Second Harmonic Restraint Verification 5 11 Fifth Harmonic Restraint 5 12 Response Time VerificatlOni e P tee e e 5 13 VERIFICATION TESTS 1 CT 50 OR 60 HZ 5 5 14 Restrained Pickup Level Verification a 5 14 Input or Tap Switch Verification nnne
32. ignored in fault current calculations Procedure One Refer to Figure 4 33 for a one line drawing of this example Refer to Figure 4 32 for the three line representation of this transformer Tap and Phase Shift Settings Step 1 Determine the primary current p of each winding MVA rating of transformer X 1 000 V LINE LINE amp 3 Use the MVA rating of the highest rated winding for all the other windings when making the calculations This procedure assures that the taps follow the voltage ratios Refer to Appendix A Setting Note 1 Ip HIGH TERTIARY LOW _ 250 000 _ 250 000 _ 250 000 P 34543 P 432 3 P 138 3 Ip 418 Ip 10 935 Ip 1 046 Step 2 Determine the CT secondary current s of each winding Ip Is CT ratio HIGH TERTIARY LOW 418 10 935 1046 Is Em Ill Is Is ea 120 600 240 Is 2349 Is 18 22 1 4 36 9171300990 Rev BE1 87T Installation 4 33 Table 4 1 List of Variables The driving input number a procedural term designating the current input terminal whose tap is the first selected The setting procedure is simplified if the driving input is the input of least current 1 Maximum external fault current in multiples of tap the larger of three phase or line ground values Driving input relay current used for matching in amperes The larger of 7r and Irc Relay input current at the maximum external three phase fault level in secondary amperes Relay
33. pu 9171300990 Rev R BE1 87T Test Procedures 5 3 In terms of current the trip current is 1 35 pu x tap 1 35 2 0 2 70A 6 100mA 3 8 Using Equation 2a 38 a 035 2 7 A Example Two Assume tap 2 tap2 3 8 slope 15 h 6 Inputs 6A 3 pu 4 2 2 114 114 3 pu 2 04 i m 38 P Check 0 35 T balance lt gt C lope 100 slope 1 zw 100 3 lt gt 0 35 0 15 0 15 3 gt 1 983 Therefore Use Equation 1 or 1a From Figure 1 2 the percentage restraint characteristic of the BE1 87T at 15 slope the minimum current where trip occurs is l tri P 1 0 15 3 53 pu In terms of current the trip current is I trip 3 53 pu x tap 3 53 2 0 7 06 A 6 100 mA 114 2 x 1 015 38 7 06 A min Using Equation 1a 5 4 BE1 87T Test Procedures 9171300990 Rev R Decreasing One Input from Balance The formula to determine the unbalance value at which the restrained trip occurs is slope unbalance gt maximum restraint or 0 35 pu whichever is greater Where unbalance absolute value of J I in per unit pu slope the RESTRAINED PICKUP LEVEL setting 15 to 60 maximum restraint larger of T or L in pu I By decreasing the input current from balance T2 The balance current is 7 1 x 1 1 When 0 35 1 0 35 I 2balance gt gt
34. restraint larger of 7 or L in pu i e or T T2 unbalance absolute value of I I in per unit pu i e Ti By increasing the I input current from balance The balance current is 1 I2 x Amps T2 1 When 0 35 I2 0 35 gt R gt R in pu sere T2 seve 100 100 ie seve 1 seve 100 100 This means the pu restraint current is to the right of the intersection of the slope characteristic with the 0 35 MPU horizontal line see Figure 1 2 5 2 BE1 87T Test Procedures 9171300990 Rev R the minimum trip point is established as N balance E y 1n pu slope RE Equation 1 100 min OR x in Amps Equation 1a 2 2 When 0 35 l balance lt in pu 100 slope 100 1 the minimum trip point is established as Iitrip min balance 0 35 pu Equation 2 OR I Trip min 2 0 5 Amps Equation 2a 2 Example One Assume tapi 2 tap 3 8 slope 15 2 Inputs 2 1 pu 2 2 1 4 1 1 pu 2 5 P I 38A 1 pu 2 1 pu T2 B 38 Check 0 35 i balance lt gt in pu slope 100 slope ae oo E oe 0 15 1 0 15 1 1 983 Therefore Use Equation 2 or 2a From Figure 1 2 the percentage restraint characteristic of the BE1 87T at 15 slope the minimum current where trip occurs is I trip 1 pu 0 35 1 35
35. the 0 35 pu or the slope line in Figure 1 2 Calculation examples are found in Section 5 1 75 BE1 87T General Information 1 5 Table 1 1 Multiples of Tap Front Seting 20 25 50 Maximum Restraint 2 33 1 75 1 40 1 17 1 00 0 875 0 778 0 700 636 KA 583 Current At Minimum Pickup In Multiples of Tap Figure 1 2 Percentage Restraint Characteristic Second Harmonic Restraint Inhibit of the restrained output occurs when the second harmonic component exceeds a pickup setting which is internally adjustable over the range of 8 to 15 of the operating current for single phase Units or 11 to 27 for three phase units The factory setting is 12 for single phase units and 18 for three phase units Fifth Harmonic Restraint Inhibit of the restrained output occurs when the fifth harmonic component exceeds a pickup setting which has an internally adjustable range of 25 to 45 of the operating current The factory setting is 35 Unrestrained Output Pickup Range Front panel thumbwheel switches adjust the pickup point of the unrestrained output over a range of 6 to 21 times the tap setting in increments of 1 x Tap Pickup Accuracy 3 of the front panel setting 1 6 BE1 87T General Information 9171300990 Rev R Outputs Output contacts are rated as follows Resistive 120 240 Vac Make 30 A for 0 2 seconds carry 7 A continuously and break 7 A 250 Vdc Make and carry 30
36. this example as shown in Figure 4 35 the high side and low side zero sequence currents must be canceled Because the CTs are connected in wye and the high side currents lead the low side currents by 30 select the A2 position This connection advances the low side phasors by 30 to match the phasors from the high side HIGH LOW Jumper Position WYE A2 On single phase units the zero sequence currents must be canceled by connecting the low side CTs in delta Step 4 Determine the relay current lp x Conversion Factor Three Phase Units Only When using either 1 or A2 jumper positions shown in Figure 2 4 multiply the secondary current 7 by the conversion factor square root of three just as if the CTs were connected in delta If the system CTs are connected in delta either three phase or single phase units the same square root of three conversion factor must be applied HIGH LOW In 2 79 1 Ig 57943 IR 2 79 Ig 10 02 Step 5 Determine the spread ratio of the relay currents largest smallest which must be less than the 4 45 capability of the BE1 87T Spread 10 02 2 79 3 59 If the spread exceeds 4 45 consider changing CT ratios or use auxiliary CTs Step 6 Determine the Driving Input DP which we define as the input assigned to the smallest current in Step 4 DP ly DP HIGH INPUT 1 9171300990 Rev R BE1 87T Installation 4 43 Step 7 Step 8 Step 9 Step 10 Step 11 4 44
37. to be changed in the field SENSING CONNECTION DIAGRAMS Each connection diagram provides as an example typical transformer terminal markings and voltage diagrams that might be found on a transformer nameplate with the winding interconnections shown The designations for high side and low side windings are for illustrative purposes only For example a diagram for a delta wye transformer is applicable to a wye delta transformer if the winding interconnections are the same The phase shifts shown in the voltage diagrams assume A B C Phase sequence rotation Each connection diagram shows the CT circuit safety ground located at the switch board panel terminal block as recommended in ANSI Standard C57 13 3 Single Phase Input Sensing Connections Typical single phase input sensing connections are illustrated in Figure 4 22 Single phase units may also be used in three phase configurations one on each phase Figure 4 23 through Figure 4 26 show several typical three phase sensing examples using three BE1 87T single phase relays Many other configurations are possible 4 20 BE1 87T Installation 9171300990 Rev R BE1 87T BREAKER Sn BREAKER ne Y INPUT 5 INPUT 4 OPTIONAL INPUTS INPUT 3 INPUT 2 INPUT 87T Figure 4 22 Typical Single Phase Sensing Connections c HOA z naam 26 c CY H X ee
38. together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The C phase differential circuit sees no current and does not respond Step 2 Connect Input 1 current to terminals A and C Connect Input 2 current to terminals A and C This verifies the A and C phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The B phase differential circuit sees no current and does not respond Step 3 Connect Input 1 current to terminals B and C Connect Input 2 current to terminals B and C This verifies the B and C phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The A phase differential circuit sees no current and does not respond Jumper Positions WYE A1 Step 1 Connect Input 1 current to terminals A and B Connect Input 2 current to terminals A and N This verifies the A and B phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The C phase differential circuit sees no current and does not respond Step 2 Connect Input 1 current to terminals A and C Connect Input 2 current to terminals N and C 9171300990 Rev R BE1 87T Test Procedures 5 21 Step 3 This verifies the A and C
39. 0 1 9 I 453 704 210 120 240 I 43 704 90 120 120 I 43 704 330 1 0 1 43 20 210 170 240 I 43 0 90 1704 120 I 43 20 330 1 0 1 3 40 150 140 240 I V3 20 30 1 0 120 1 V3 70 270 1 Table 4 4 is for reference only and applies to three phase units with Input at zero amperes 2 For A B C rotation MAINTENANCE BE1 87T relays require no preventative maintenance other than a periodic operational check If the relay fails to function properly contact Technical Sales Support at Basler Electric to coordinate repairs STORAGE This protective relay contains aluminum electrolytic capacitors which generally have a life expectancy in excess of 10 years at storage temperatures less than 40 C 104 F Typically the life expectancy of a capacitor is cut in half for every 10 C rise in temperature Storage life can be extended if at one year intervals power is applied to the relay for a period of 30 minutes TEST PLUG Test plugs Basler p n 10095 provide a quick easy method of testing relays without removing them from their case Test plugs are simply substituted for the connection plugs This provides access to the external stud connections as well as to the internal circuitry 4 50 BE1 87T Installation 9171300990 Rev R Test plugs consist of a black and red phenolic molding with 20 electrically separated contact fingers connected to 10 coaxial binding po
40. 00990 Rev R BE1 87T Installation 4 29 s A B B ae B Ae B Pu 5 L _ 1 87 M y Switch Hy Xo OR H X BUSHING AS 16 BA WE board APPROPRIATE 18 N terminal 14 E blocks TA we N 13 D2751 25 m 04 16 99 en Phase shift jumper position on analog board 2 WITH UNLOADED TERTIARY NOTES A AN ALERNATIVE TO GROUNDING THE CORNER OF THE THE DELTA CONNECTED CTs IS TO CONNECT THE GROUND TO LEADS CONNECTED TO TERMINALS 13 AND18 A IF THERE IS NOT A DELTA TERTIARY OR IF THE WYE WINDING IS UNGROUNDED IT IS UNNECESSARY TO DELTA SHIFT THE CURRENTS FOR ZERO SEQUENCE BLOCKING Figure 4 31a Three Phase Connections Wye Wye or Autotransformer Configuration CT Compensation The Wye Wye or Autotransformer does not require phase shift compensation However it is necessary to Delta compensate the currents to block zero sequence currents being supplied by the transformer bank This is shown in Figure 4 31a by connecting the CTs in Delta In Figure 31b compensation is shown by internal phase compensation jumper setting 4 30 BE1 87T Installation 9171300990 Rev R H 3 X C B T H X es H X E A as els BE1 87T L 17 C Switch E 16 board Ho
41. 11 amp 13 Input 1 for both single phase and three phase units Step 2 Set the UNRESTRAINED PICKUP LEVEL switch to position A 6 x TAP Increase the input current until the UNREST TRIP LED lights disregard the REST TRIP LED This should occur at 12 0 A 3 as indicated in Table 5 3 Step 3 Repeat Step 2 using the other UNRESTRAINED PICKUP LEVEL switch positions given in Table 5 3 Step 4 Three Phase Units Only Repeat Steps 1 through 3 for phase B of input 1 terminals 12 amp 13 and Phase C of input 1 terminals 14 amp 13 Table 5 3 Unrestrained Pickup Verification 5 A 50 or 60 Hz Unrestrained Input 1 Tap Input Current at Pickup Level Position Pickup 3 A 6 x TAP 12 0A J 14 x TAP 28 0A S 21 x TAP 42 0A Second Harmonic Restraint Verification Step 1 Set the INPUT 1 tap switches to the 2 0 A position Connect the relay as appropriate refer to Figures 5 2 through 5 5 using terminals 11 amp 13 Input 1 for both single phase and three phase units 9171300990 Rev R BE1 87T Test Procedures 5 11 Step 2 Three Phase Units Only Set the Calibrate toggle switch S2 letter 2 of Figure 2 4 to the CAL position on each of the three Analog 1 boards These three toggle switches are readily accessible on the right side of the relay when withdrawn from the case It is not necessary to pull out the circuit boards NOTE With two current sources in parallel apply the fundamental frequ
42. 71300990 Rev R BE1 87T Setting Notes A 9 Figure 5 illustrates how a lower Rs value reduces the difference between SF and SF SF and SF for Zc 2 ZB 0 5 Rs 0 2 0 4 0 20 40 60 80 100 IF Figure 5 Reducing the Difference between SF and SF Conclusion This analysis shows that the easy to apply SF based on the ANSI Accuracy Class may yield optimistic results in cases where the CT internal resistance is significant The Excitation curve method requiring more data yields more accurate results and should be used when the SF is marginal A 10 BE1 87T Setting Notes 9171300990 Rev R Basler Electric ROUTE 143 BOX 269 HIGHLAND IL 62249 USA http www basler com info basler com PHONE 1 618 654 2341 FAX 1 618 654 2351
43. 751 28 02 12 98 Figure A 5 BE1 87T Slope vs and Ir D2751 29 02 12 98 Figure A 6 BE1 87T Margin vs and Ir 9171300990 Rev R BE1 87T Setting Notes HdO IS NIDAVIN SETTING NOTE 6 Inrush vs Unrestraint Tap RCH RCL N LOAD D2751 20 87T 02 03 98 Compare the unrestraint pickup setting defined in NOTE 4 to the transformer in rush current I The UR tap is set at 70 of IE the maximum pu through fault current r Tx RCH The worst case 3 Phase fault occurs when the source impedance is negligible 0 1 Then Ir X pu at the transformer OA base T Fora X7 6 06 167PU The unrestraint tap MPU would be set for 0 7 x 16 7 117 pu Note that 11 7 pu value is different from the relay UR tap setting The inrush current is generally assumed to be less than 10 times the nominal transformer current 10 pu on the OA base For this worst case example the maximum inrush current is below the UR threshold For significant source impedance values we assume that the inrush current will decrease in proportion to the decrease in the fault current and thus maintain security with the recommended settings A 6 BE1 87T Setting Notes 9171300990 Rev R SETTING NOTE 7 CT Performance Evaluation Saturation Factor The secondary current delivered by a current transformer to a relay circuit is always less than the current available from an ideal CT The ideal or ratio cu
44. 90 Rev R BE1 87T General Information 1 7 1 8 Figure 1 3 Unrestrained Response Times Figure 1 4 Restrained Response Times BE1 87T General Information 9171300990 Rev R Isolation In accordance with IEC 255 5 and ANSI IEEE C37 90 1989 one minute dielectric high potential tests as follows All circuits to ground 2121 Vdc Input to output circuits 1500 Vac or 2121 Vdc Power Supply Refer to Table 1 3 Table 1 3 Power Supply Specifications Burden at Burden at Nominal Input Input Voltage Nominal Nominal Type Voltage Range Energized De energized J Mid 125 Vdc 62 150 Vdc 9 0 W 64W Range 120 Vac 90 132 Vac 21 0 VAx 19 8 VA K Mid 48 Vdc 24 60 Vdc 85W 62W me 22 48 24 60 8 5 W 2W 5 250 140 280 9 5W 6 4W At 55 65 Hz T Type L power supply may require 14 Vdc to begin operation Once operating the voltage may be reduced to 12 Vdc Surge Withstand Capability Qualified to ANSI IEEE C37 90 1 1989 Standard Surge Withstand Capability SWC Tests for Protective Relays and Relay Systems and IEC 255 5 Impulse Test and Dielectric Test Radio Frequency Interference Maintains proper operation when tested in accordance with RFI IEEE C37 90 2 1987 Trial Use Standard Withstand Capability of Relay Systems to Radiated Electromagnetic Interference from Transceivers UL Recognition UL Recognized per Standard 508 UL File No E97033 Note Output contact
45. A for 0 2 seconds carry 7 A continuously and break 0 3 A 500 Vdc Make and carry 15 A for 0 2 seconds carry 7 A continuously and break 0 1 A Inductive 120 240 Vac 125 250 Make and carry 30 A for 0 2 seconds carry 7 A continuously and break 0 3 A L R 0 04 Target Indicators Target indicators may be either internally operated or current operated operated by a minimum of 0 2 A through the output trip circuit When the target is current operated the associated output circuit must be limited to 30 A for 0 2 seconds 7 A for 2 minutes and 3 A continuously Single Phase Units Either an internally operated or a current operated target is supplied as selected by the Style Number for each trip output i e the restrained and the unrestrained functions Three Phase Units Either internally operated or current operated targets as selected indicate the function restrained or unrestrained that caused the trip and the tripped phase A B C Harmonic Attenuation Refer to Table 1 2 Table 1 2 Harmonic Attenuation Parameter Minimum Attenuation at Indicated Fundamental 50 Or 60 Hz Models 50 60 Hz 100 120 2 150 180 Hz 250 300 Hz Through Current 12 dB 2nd Harmonic Restraint 12 dB m5 12 dB 12 dB 12 dB 5th Harmonic Restraint 12 dB 12 dB 12 dB s 12 dB Timing Refer to Figure 1 3 for Unrestrained Response Times and For 60 Hz units only Figure 1 4 for Restrained Response Times ET KI e 91713009
46. B qe Hea 2 5 X SWITCH BOARD amp TENE 5 5 5 TERMINAL BLOCKS BE1 87T 1 e 13 Coy 2 12 y BE1 87T 2 i EN 12 111 BE1 87T 3 13 W 2 12 11 17 H X D1186 02 H H A Figure 4 23 Single Phase Connections Delta Wye Configuration 9171300990 Rev R BE1 87T Installation 4 21 c He H X o5 A Heer 9 Ho e o X SWITCH BOARD TERMINAL BLOCKS 4 22 BE1 87T 1 13 12 o 2 11 4 1 87 2 2 12 13 1111 BE1 87T 3 13 2 12 11 1 H X D1186 20 vsd p p p Figure 4 24 Single Phase Connections Wye Wye Configuration BE1 87T Installation 9171300990 Rev R SWICH BOARD TERMINAL BLOCKS BE1 87T 1 c 1 11 12 e rV Figure 4 25 Single Phase Connections Delta Delta Wye Configuration 9171300990 Rev R BE1 87T Installation 4 23
47. BE1 87T Introduction i First Printing June 1990 Printed in USA 1990 1997 1999 2000 2003 2005 2007 Basler Electric Highland Illinois 62249 USA All Rights Reserved September 2007 CONFIDENTIAL INFORMATION of Basler Electric Highland Illinois USA It is loaned for confidential use subject to return on request and with the mutual understanding that it will not be used in any manner detrimental to the interest of Basler Electric It is not the intention of this manual to cover all details and variations in equipment nor does this manual provide data for every possible contingency regarding installation or operation The availability and design of all features and options are subject to modification without notice Should further information be required contact Basler Electric BASLER ELECTRIC ROUTE 143 BOX 269 HIGHLAND IL 62249 USA http www basler com info basler com PHONE 1 618 654 2341 FAX 1 618 654 2351 ii BE1 87T Introduction 9171300990 Rev R REVISION HISTORY The following information provides a historical summary of the changes made to the BE1 87T instruction manual 9171300990 Revisions are listed in reverse chronological order Manual Revision and Date Change R 09 07 e Replaced magnetic type targets with electronic type targets e Updated power supply burden data and output contact ratings e Updated front panel illustrations to show laser graphics e Moved content of Section 6
48. Determine the Driving Input Tap T If both relay currents are between 2 0 and 8 9 amperes the tap settings can be set equal to the relay currents to the nearest 0 1 ampere However choosing the 2 0 tap setting for the minimum input will yield maximum sensitivity 2 00 Determine the desired Tap for Input 2 I Tp 2 qm 10 02 0 7 18 Select taps by rounding Tp to the nearest tenth T 2 0 To 7 2 Determine the CT mismatch My 100 Current Ratio Tap Ratio the smaller of the above Fri fi Ig T 100 Smaller 2 79 20 10 02 7 2 2 ET _ 100278 0 2778 Smaller 02778 0216 or 0 22 96 Determine the total mismatch M 7 Mrz My LTC Add the maximum CT mismatch My based on the power transformer in the neutral tap position to the total permissible tap excursion from neutral In this example a 10 load tap change LTC must be accommodated Therefore 0 22 10 10 22 BE1 87T Installation 9171300990 Rev R Verify CT Performance NOTE This procedure uses the ANSI accuracy class method See Appendix A Setting Note 7 for more information Step 12 Determine the maximum CT secondary fault current for external faults at F for three phase lrg for single phase Refer again to Figure 4 35 for this example HIGH LOW 1916 10603 69 160 32A 66A 1171 11231 TFG 90 IFG T60 2195 70A Step 13 Determine
49. ERATING PRECAUTIONS on page 4 1 and RELAY DISASSEMBLY Precautions on page 4 11 Step 1 Step 2 Insert the cradle assembly into the relay case then Three Phase Units with Sensing Input Type G Remove the lower connection plug first Then remove the upper connection plug Insert two Test Plugs P N 10095 or equivalent in place of the top and bottom connection plugs For further information refer to TEST PLUG in Section 6 MAINTENANCE Terminal 20 trip output common shown in Figure 4 10 must be isolated for this test All other styles Replace the top connection plug with a Test Plug P N 10095 or equivalent For further information refer to TEST PLUG in Section 6 MAINTENANCE Terminal 9 trip output common shown in Figures 4 7 through 4 9 must be isolated for this test Using an ammeter and phase angle meter measure the magnitude and phase angle of each current input testing two inputs at a time Begin with Inputs 1 and 2 CAUTION When more than two inputs are present all inputs not being tested must be shorted to Step 3 ground Single Phase Units Relay must not trip when the current to each input of the pair being tested is equal to the other in magnitude and the two currents are 180 out of phase e g Inputs 1 and 2 measured with Inputs 3 4 and 5 shorted For input terminal numbers see Table 4 3 Three Phase Units Relay must not trip when the current to Input 1 is equal to that of Input 2 in m
50. INSTRUCTION MANUAL FOR TRANSFORMER DIFFERENTIAL RELAY BE1 87T Basler Electric INPUT 1 INPUT 2 INPUT 3 INPUT 4 5 0 8 0 5 0 8 0 5 0 8 0 5 0 8 0 UNRESTRAINED PICKUP LEVEL RESTRAINED PICKUP LEVEL OF TRIP RU ws ull oo 00000009 TRIP ACTIVE K r THRU current 15 20 25 3s 4o as so BE1 87T P TRANSFORMER DIFFERENTIAL Q TAM Style No D2E A1J 0150 POWER Serial No XXXXXXXXXXXX 99 OO FUNCTION U S PATENT 5 014 153 PATENTED IN CANADA 1993 P0052 22 Basler Electric Publication 9171300990 Revision R 09 07 INTRODUCTION This instruction manual provides information about the operation and installation of the BE1 87T Transformer Differential relay To accomplish this the following information is provided e General Information and Specifications Controls and Indicators e Functional Description e Installation e Test Procedures WARNING To avoid personal injury or equipment damage only qualified personnel should perform the procedures in this manual NOTE Be sure that the relay is hard wired to earth ground with no smaller than 12 AWG copper wire attached to the ground terminal on the rear of the unit case When the relay is configured in a system with other devices it is recommended to use a separate lead to the ground bus from each unit 9171300990 Rev R
51. OL ay EIER 1 9 Operating Temperature sssssssssssesseeeeeeene eene nnne nnn nisi nnns innen rens nnn sn nene nanna 1 10 Storage Temperatures orae de dca dt va de 1 10 ep 1 10 CaSe ipa PEERS 1 10 SECTION 2 e CONTROLS AND INDICATORS 2 inna sa u u u 2 1 LOCATION OF CONTROLS AND INDICATORS sse ener nnne ns 2 1 SECTION e FUNCTIONAL 3 1 GENERAL SS T 3 1 Wes 3 1 Current TransfOFm ls iiec ice n eee Ere 3 1 snot 3 1 PES 3 1 30 Internal Phase Shift Three Phase Relays 3 1 Restrained Trip Output sentent nnns Hua aa sia aa as 3 3 Unrestrained OUtP t q u u sua aus aa aa tren tenens 3 3 Auxiliary Relay OPton NP 3 4 geo 3 4 Power Supply Status Output Optional 3 4 Indicators 3 4 OF TD Tapa n 3 5 9171300990 Rev R BE1 87T Introduction vii GENERAL
52. S2 located on the mother board and shown in Figure 2 4 allow the auxiliary output to operate in conjunction with a restrained trip an unrestrained trip or both EQUIPMENT REQUIRED The following test equipment or equivalent is required for either the Operational Tests or the Verification Tests 1 Two current sources with independently regulated current outputs Must be able to produce outputs 180 out of phase If harmonic testing is desired harmonic capability is also required Counter 0 to 0 5 second range Two Test Plugs Basler p n 10095 see Test Plug in Section 4 Installation Extender Card Basler p n 9165500100 as shown in Figure 5 1 Phase angle meter or oscilloscope with an ungrounded plug or ground isolation transformer oF ON 9171300990 Rev R BE1 87T Test Procedures 5 1 CAUTION If an oscilloscope or meter is to be connected to the internal relay circuitry it must be isolated from ground The internal circuits are not grounded to the case or isolated from the power inputs source BE1 87T D439 001 1 81 94 Figure 5 1 Illustrating Use of Extender Board RESTRAINED PICKUP TESTING EXAMPLES Increasing One Input from Balance The formula to determine the unbalance value at which the restrained trip occurs is sl unbalance gt ET maximum restraint or 0 35 pu whichever is greater Where I2 T T2 slope the RESTRAINED PICKUP LEVEL setting 15 to 60 1 I2 maximum
53. Section 7 Difference Data Changed previous Section 7 Manual Change Information to Section Added an Appendix A to clarify the setting procedures Added an index to help the user find information easier Changed the format of the manual J 01 96 Deleted Difference Data formerly Section 7 and included notes for users of Type F relays Moved all information regarding relay settings and checking relay setting from Section 5 Testing and Setting to Section 4 Installation Section 5 now contains information on test procedures Combined 50 and 60 Hz Verification Tests Various editorial changes Reformatted instruction manual as Windows Help file for electronic documentation 1 01 95 Added outline box to Figure 5 8 to highlight the figure Page 5 42 Step 5 changed should be less than 4 45 to must be less than 4 45 Added note to page 5 43 Step 10 and corrected the formula in Step 10 Page 5 45 Step 18 corrected formula and high side results and Step 19 changed last sentence from H 13 x tap to S 21 x tap Page 5 46 Steps 20 and 21 corrected figure references H 12 94 Page 1 6 changed Specification for Restrained Output Pickup Accuracy Changed Section 5 Testing and Setting Verification Tests all models Steps 1 4 5 and 8 and Table 5 4 Page 5 50 Jumper Positions Wye Delta 1 Step 3 Corrected Input 2 terminal identifications Page 5 51 Jumper Positions Delt
54. U S PATENT 5 014 153 PATENTED IN CANADA 1993 Figure 2 3 Sensing Input Range 2 or 4 Three Phase Two Inputs BE1 87T Controls and Indicators 9171300990 Rev R LH EDGE OF ANALOG 2 BOARD THE 4TH BOARD DOWN COUNTING THE der ues BOARD BE1 87T VR2 Ll TP 12V P0052 26 SECTION OF THE VERTICAL lt MOTHER BOARD AT LEFT j REAR OF RELAY Figure 2 4 Controls Mounted Inside the Relay 9171300990 Rev R BE1 87T Controls and Indicators 2 7 2 8 Ede P0052 27 ES Basler Electric INPUT 1 INPUT 2 INPUT 3 INPUT 4 INPUT 5 5 0 8 0 5 0 8 0 semNG A s c p e r e na x c w wu pe n s xme 7 1 12 13 14 5 t6 17 18 v9 20 24 UNRESTRAINED PICKUP LEVEL OF TRIP BE1 87T x TRANSFORMER DIFFERENTIAL Q FAX Style No D3E A1J D1S0F POWER Serial No XXXXXXXXXXXX PUSH TO ENERGIZE OUTPUT O L Function U S PATENT 5 014 153 PATENTED IN CANADA 1993 BE1 87T Controls and Indicators Figure 2 5 Sensing Input Range 2 or 4 Option 1 1 Single Phase Five Inputs OF TRIP Option 9171300990 Rev R SECTION 3 FUNCTIONAL DESCRIPTION GENERAL BE1 87T relays are solid state devices that protect transformers by providing output contact closure when the scaled current into the protected transformer does not equal the scaled current out within defined limits These relays are harmonically restrained to prevent trippi
55. VEL setting slope to S 60 9171300990 Rev R BE1 87T Installation 4 41 Procedure Two Refer to Figure 4 35 for a one line drawing of this example Data 12 20MVA 2 2 100 69 gt 1247 600 5MR 1200 5MR zs 300 5T LOAD 800 5T 1171 19 11 231 19 x1 O LTC D1873 21 Z 5 12MVA 0371598 Figure 4 35 Two Winding Transformer Relay Setting Calculation Example SPECIFICATIONS CT Ratio CT Tap CT Accuracy Class CT Resistance ohms One Way Lead Burden ohms XFMR Connection CT Connection Input Fault Current Three Phase Fault Current Single Phase Standard connection High voltage leads low voltage by 30 Tap and Phase Shift Settings Step 1 Determine the full load primary current lp of each winding u MVA ratingof transformer x 1 000 VLINE LINE V3 Ip Use the top kVA rating of the transformer when making the calculations HIGH LOW 20 000 r 20000 P SN P 12 413 Ip 167 35 Ip 925 98 4 42 BE1 87T Installation 9171300990 Rev R Step 2 Determine the CT secondary current 16 Ip Ts CT ratio HIGH LOW 167 35 I 925 98 S 60 S 160 Is 2 79 1 5 79 Step 3 Units Only Adjust the phase compensation jumpers on Analog Board 2 shown in Figure 2 4 or use the procedure listed in TESTING THREE PHASE UNITS WITHOUT CHANGING JUMPERS in Section 5 Because of the grounded winding in
56. a2 Delta2 Step 2 Corrected verification statement G 09 94 Changed all sections to reflect new Option 1 1 Added to Section 5 four examples for testing relays to clarify test procedures Added to Section 5 one procedure for setting relays Corrected typographical and illustration errors BE1 87T Introduction 9171300990 Rev R Manual Revision and Date Change F 03 93 Changed formula pages 5 4 5 10 5 16 and 5 22 from the square root of K over t to K over the square root of t E 01 93 Manual was revised to incorporate a revision in the relay that made sensing input type F obsolete and included the 1 A 60 hertz and 5 A 50 hertz model relays Section 5 Test Setup diagrams were changed to clarify relay connections Added three relay Internal Connection diagrams Changed unrestrained maximum time to trip reference old Tables 5 4 and 5 8 new Tables 5 4 5 8 5 12 and 5 16 Renamed Section 7 Manual Change Information to Section 8 Manual Change Information and added new Section 7 Difference Data to support BE1 87T relays with Sensing Input Type F D 06 92 Manual was revised to include the 1 A 50 Hz model relay and reformatted to a new Instruction Manual style Additional connection diagrams were included in Section 4 and test plug information was added to Section 6 Minor typographical errors were also corrected C 03 91 Table 5 1 was expanded and Figure 5 4 Test S
57. ach phase G Three phase three inputs each phase moou r Step 2 Connect the input being tested to the current source as shown in the appropriate TEST SETUP Figures 5 2 through 5 5 Step 3 Set the input under test to the 3 9 tap position as shown in Table 5 2 Set the RESTRAINED PICKUP LEVEL switch to position A 1596 Apply current to the input under test increasing 5 10 BE1 87T Test Procedures 9171300990 Rev R the current until the REST TRIP LED lights At this point the input current should be 1 36 A 6 100 mA Step 4 Repeat Step 3 for the additional tap positions shown in Table 5 2 This verifies the accuracy of all the binary combinations of the rotary switches Step 5 Test the other inputs by reconnecting to the next pair of terminals for your relay and repeating Steps 3 and 4 The successful completion of these tests will verify the electrical integrity of all the tap switches Table 5 2 Input Verification 5 A 50 or 60 Hz Position Input Current Range at Pickup 3 9 1 18 1 55A 4 3 1 31 1 70A 6 4 2 01 2 47 7 8 2 47 2 99 Pickup occurs at 0 35 x Tap See Figure 1 2 T setting of the upper and lower INPUT switches of the input being tested Reference LOCATION OF CONTROLS AND INDICATORS Unrestrained Pickup Verification Step 1 Set the INPUT 1 tap switches to the 2 0 A position Connect the relay as appropriate refer to Figures 5 2 through 5 5 using terminals
58. agnitude and the phase angle is as shown in Table 4 4 If there are three inputs per phase interchange Inputs 2 and 3 and repeat the procedure this time with magnitudes and phase angles as shown in Table 4 4 Testing may require six synchronized current sources Using the Test Plug reestablish all input connections and verify that the front panel REST TRIP and UNREST TRIP LEDs are extinguished This assures that the X TAP settings and jumper settings refer to Figures 4 20 4 21 and 4 27 are within acceptable parameters and that the differential current is below pickup If the REST TRIP or UNREST TRIP LEDs light recheck the system current inputs and relay settings If actual waveforms as sensed by the BE1 87T are desired a procedure using a circuit board Extender Card shown in Figure 5 1 and an oscilloscope is available Table 4 3 Single Phase Input Terminals 9171300990 Rev R BE1 87T Installation 4 49 Table 4 4 Input Conditions For Non Trip Three Phase Sensing 30 Phase Shift Compensation Jumper Settings Ref Figure 4 27 WYE WYE A1 A1 or A2 A2 In these cases input currents are equal and 180 out of phase Input 1 is 1 Input 2 is WYE Input 1 is WYE Input 2 is A1 Input 1 is A2 Input 2 is WYE Input 1 is WYE Input 2 is A2 NOTES Input 1 Input 2 1 0 180 140 240 170 60 1 04 120 170 4 300 1 0 16 3 0 150 1 0 2407 1 43 704 30 10 120 I 43 704 27
59. ained slope setting S is a function of the total mismatch and the power transformer exciting current This provides an ample security margin with respect to the characteristic kneepoint of the BE1 87T Refer to Figure 4 34 Specifically if the maximum saturation factor 5 from Step 16 exceeds 0 5 set the RESTRAINED PICKUP LEVEL to setting K which is equal to 60 as shown in the table on the front panel For all other cases including this example use the following equation ses rn Where S restrained slope setting Mr total mismatch in percent rated self cooled current of the power transformer in multiples of tap Mris 10 2 from Step 11 and 7 is 0 84 Step 20 35 10 2 3 23 4 0 84 26 596 3 Because the maximum saturation factor S for this example is less than 0 5 from Step 16 use the next highest slope Select position D which 30 For examples of suitable slope settings see Table 4 2 BE1 87T Installation 9171300990 Rev R CHECKING THE RELAY SETTINGS AND SYSTEM INPUTS Steps 1 and 2 check that the current inputs from the power transformer are correct and consistent with the BE1 87T settings The remaining steps check that the relay settings are within acceptable parameters CAUTION Do NOT install connection plugs apply power remove circuit boards or carry out any of the other instructions given unless you are thoroughly familiar with the instructions in the sections on RELAY OP
60. cial reed relay is placed in series with the contact to signal the target indicator The series impedance of the reed relay is less than 0 1 ohm Current in the output circuit must be limited to 30 amperes for 0 2 seconds 7 amperes for 2 minutes and 3 amperes continuously 3 4 BE1 87T Functional Description 9171300990 Rev R NOTE Prior to September 2007 the BE1 87T target indicators consisted of magnetically latched disc indicators These mechanically latched target indicators have been replaced by the electronically latched LED targets in use today of Trip When the of trip pushbutton Q is pushed eight LEDs shown in Figure 2 5 are used to indicate the percentage of operating current to Minimum pickup LED M also lights or Slope characteristic pickup LED S also lights The eight LEDs represent the following percentages 1 LED 3 Yellow LED 2 LEDs 7 Yellow LED 3 LEDs 11 Yellow LED 4 LEDs 20 Red LED 5 LEDs 40 Red LED 6 LEDs 60 Red LED 7 LEDs 80 Red LED 8 LEDs 100 Red LED A bar chart above the LEDs shows the relative percentage of trip 9171300990 Rev R BE1 87T Functional Description 3 5 3 6 This page intentionally left blank BE1 87T Functional Description 9171300990 Rev R SECTION 4 INSTALLATION GENERAL When not shipped as part of a control or a switchgear panel the relay is shipped in a sturdy carton to prevent damage during transit Immediately upon rec
61. ction for power transformers and are available in either Single Phase or Three Phase configurations The solid state BE1 87T compares the currents entering and leaving the protected transformer If a fault is detected the relay initiates a trip signal to isolate the power transformer This limits damage to the transformer and minimizes the impact on the power system BE1 87T relays use three types of restraint e Percentage of through current e Second harmonic e Fifth harmonic Selectivity in differential relaying is based on the ability to distinguish between internal and external faults This is achieved by comparing the currents into and out of a power transformer Comparing these currents often requires more than two inputs For example e Power transformers may have a significant portion greater than 10 96 of the current flowing in a third or tertiary winding e Power transformers can have multiple breakers for a given winding e g ring bus or breaker and a half bus BE1 87T relays are available with up to five restraint inputs for the single phase unit and up to three restraint inputs per phase for the three phase unit 9171300990 Rev R BE1 87T General Information 1 1 APPLICATION In general power transformers have different values of current flowing through their primary secondary and tertiary windings These currents have specific phase relationships depending upon the connections of the individual windings e g wye del
62. current automatically after a suitable time interval This can be calculated by using the following equation K Jr Where K 50 or 50 x tap whichever is less t the time in seconds that the current flows Restrained Pickup Verification Step 1 Step 2 Step 3 Step 4 Connect the relay as appropriate refer to Figures 5 2 through 5 5 beginning with input terminals 11 and 13 for the initial tests Do not apply power at this time Observing the precautions provided in Section 4 HELAY DISASSEMBLY remove the relay from its case Then remove the front panel to gain access to the printed circuit boards Remove the Analog 1 board one per phase shown in Figure 4 19 Connect the Input Grounding jumpers to the disabled position Refer to Figure 4 20 for relays with Option 1 0 and Figure 4 21 for relays with Option 1 1 for correct positioning For further information see Grounding Unused Inputs in Section 4 After testing is complete and prior to placing the relay in service it may be necessary to reposition the jumpers Three Phase Units Only Check that all of the 30 Phase Shift Compensation jumpers on the Analog Board 2 shown in Figure 4 27 are in the WYE position If not reposition these jumpers accordingly NOTE It is possible to test three phase units without changing the 30 Phase Shift Compensation jumpers from the in service positions Refer to Testing Three Phase Step 5 Step 6 Step 7
63. d by 30 or passed through unchanged Compensating phase shift direction shown as the Phase Shift Setting circuit in Figure 3 1 is determined by the position of three jumpers on the internal Analog 2 Board The location of these jumpers is shown in Figure 2 4 The internal phase shift will accomplish the corresponding zero sequence blocking The current magnitude will be increased by 3 and must be taken into account in the tap setting explained later in detail in Section 4 9171300990 Rev R BE1 87T Functional Description 3 1 OPERATING POWER ENED POWER SUPPLY TO INTERNAL U OSHIFT SETTING CIRCUITRY SENSOR POWER 30 30 0 SUPPLY STATUS IN 1 CALCULATE MAXIMUM INDIVIDUAL CURRENT OF TRIP IN 2 RESTRAINED gA Q 3 10 IN 4 SECOND HARMONIC IN 5 RESTRAINT FILTERS COM IF lop gt UNREST UNREST UNRESTRAINED NREST SETTIN TRIE a SETTING 6TO21 j THEN TRIP TIMES TAP TO OTHER PHASES THREE PHASE ONLY BE1 87T D741 001a 7 11 94 Figure 3 1 Functional Block Diagram NOTES 1 Present in three phase units ONLY 2 Inputs 4 and 5 are available in single phase units ONLY 3 settings are calibrated to a specified percentage of the harmonic to the fundamental See Harmonic Restraints for factory settings 4 Phase Targets are supplied on three phase units ONLY 5 Restrained Trip Contact e contact for single phase units e One contact or one contact per phase available on three phase
64. de system protection Always be sure that external operating monitored conditions are stable before removing a relay for inspection testing or servicing Be sure that connection plugs are in place before replacing the front cover CAUTION To prevent possible false tripping the upper connection plug should be in place prior to removing or installing the lower connection plug 4 Thumbwheel switches should not be changed while the relay is in service Momentary undesired indications and outputs may occur WARNING The TEST PROCEDURES require familiarity with solid state relay circuits To avoid personal injury or equipment damage do not proceed unless qualified in this area MOUNTING Because the BE1 87T Transformer Differential Relay is of solid state design It does not have to be mounted vertically Any convenient mounting angle may be chosen The BE1 87T relay is supplied in a standard M1 size drawout case and can be either semi flush or projection mounted Option 4 Refer to Figures 4 1 through 4 6 for outline dimensions and panel drilling diagrams NOTE Several procedures in this manual require the removal of printed circuit boards Refer to the topic RELAY DISASSEMBLY before installing the BE1 87T 9171300990 Rev R BE1 87T Installation 4 1 4 2 6 65 168 91 15 32 389 13 D1924 28
65. dicating that the inhibit point has been reached Note the magnitude of the fifth harmonic component at the inhibit point To calculate the fifth harmonic inhibit percentage divide the current measured in Step 3 by the current applied in Step 2 Divide the harmonic current by the fundamental current Factory setting is 35 0 3 for both single phase and three phase units Three Phase Units Only Repeat Steps 1 through 4 for phase B terminals 12 amp 13 and phase C terminals 14 amp 13 BE1 87T Test Procedures 9171300990 Rev R Response Time Verification Step 1 Step 2 Step 3 Step 4 Step 5 Step 6 Step 7 Step 8 Step 9 Step 10 Connect the relay as appropriate refer to Figures 5 2 through 5 5 Set the RESTRAINED PICKUP LEVEL switch phase A to A 15 Place all of the INPUT switches on the 2 0 A tap position Apply 2 0 A at 50 or 60 Hz as appropriate for the style to Input 1 terminals 11 amp 13 on both single and three phase styles and to Input 2 terminals 12 amp 13 on Single Phase and terminals 15 amp 18 on three phase Perform a restrained trip at 2 x Pickup by stepping the Input 2 current 3 4 A Note the time interval between initiation of the simulated fault and the closure of the restrained output contact The trip time should be less than that shown in Table 5 4 Repeat Step 4 at Io 10 x Pickup Note that with Input 1 at 2 0 A Input 2 current should be stepped to 9 0 A
66. e This is shown in Figure 4 32 by selecting phase compensation jumper position A2 for these inputs This also provides zero sequence blocking for these inputs since this transformer configuration is a source of zero sequence currents 4 32 BE1 87T Installation 9171300990 Rev R SETTING THE BE1 87T The following setting procedures include two examples 1 Using the MVA rating of the highest rated winding for all the other windings when making the calculations 2 Using the top kVA rating of the transformer Each procedure can be used as a means to understand the principles involved and by replacing the variables of the example can become a procedure of general application Variable abbreviations and definitions are provided in Table 4 1 List Of Variables Method Both procedures determine 1 The matching tap and slope settings required to implement the restrained function and 2 The unrestrained pickup setting as a multiple of the BE1 87T tap setting i e the INPUT switches The matching tap procedure is conventional providing tap values proportional to the normal currents as seen by the relay An exception occurs with multiple winding banks where zero balance current is assumed in each pair of windings successively NOTE The component of the input current is effectively blocked by the gapped cores of the input CTs Therefore for offset fault currents or magnetic inrush the dc component of the waveform can be
67. e For wye connected CTs VBG Irc 2RL Rr Where lg determined in Step 12 R one way lead resistance in ohms relay resistance in ohms lt 0 05 ohm For delta connected CTs Vz is a function of the proportion of positive sequence to zero sequence currents but may be approximated by the same equation Neglecting Rr use Rw and from Figure 4 33 HIGH TERTIARY LOW Vac 28 2 0 7 NONE 38 2 0 7 39 2 53 2 Step 15 Determine the effective CT accuracy class Vcg Base Accuracy Number of CT Turns in Use 5 Maximum Ratio HIGH TERTIARY LOW 600 3000 1200 400 VCE 800 400 ce G00 En 800 5000 CE 400 400 800 240 Step 16 Determine the saturation factor Sg Note Vz is the largest burden voltage from steps 13 and 14 SF Vos HIGH TERTIARY LOW 5 392 _ 154 5 532 400 F 800 240 0 1 0 02 0 22 4 38 BE1 87T Installation 9171300990 Rev R NOTE Maximum recommended S 0 5 Instantaneous Unrestraint Unit Setting Step 17 Determine the maximum external fault multiple g For wye connected CTs and with WYE jumpers on Analog Board 2 shown in Figure 2 4 Ir Maximum Relay Fault Current E T Corresponding Tap For delta connected CTs or with 1 or A2 jumpers on Analog Board 2 shown in Figure 2 4 and based on a phase to phase fault Refer to Appendix A Setting Note 3
68. each input then reduce the Input 2 current or increase the Input 1 current until the REST TRIP LED lights This should occur as the input current being adjusted reaches the level given in the Trip Amperes column for the respective input If the relay has more than two inputs reconnect the relay by substituting the Input 3 terminals for the Input 2 terminals Then repeat Steps 6 and 7 using the Input 2 values of Table 5 1 for Input 3 If there are more than three inputs as in some single phase units continue substituting every higher numbered input for Input 2 each time comparing the input under test against Input 1 as in Steps 6 and 7 9171300990 Rev R BE1 87T Test Procedures 5 9 Step 9 Three Phase Units Only Repeat Steps 6 7 and 8 for phases and C Refer to Figures 5 2 through 5 5 as appropriate for the terminal numbers of the phase B and C inputs Table 5 1 Restrained Pickup Test 5 A 50 or 60 Hz Input 1 Tap 2 0 Input 2 Tap 3 8 Increasing Input 1 Decreasing Input 2 25 5 33 0 42 5 70 0 44 60 6 0 3 11 4 3 15 00 1 00 4 56 0 37 Input or Tap Switch Verification Each input is scaled using a combination of two rotary switches Verify the switches as follows Step 1 Determine the Sensing Input Type the first digit of the Style Number shown on the front panel Single phase two inputs Single phase three inputs Single phase four inputs Single phase five inputs Three phase two inputs e
69. ed in delta Remember that if system CTs are connected in delta the same square root of three conversion factor must be applied HIGH TERTIARY LOW INPUT 1 INPUT 2 INPUT 3 Ig 23 4943 IR 1822 1 Ig 243643 Ig 26 04 IR 18 22 Ig 7 55 Step 5 Determine the spread ratio of the relay currents largest smallest Spread 18 22 6 04 3 0 Step 6 Determine the Driving InputError Bookmark not defined DP which we define as the input assigned to the smallest current in Step 4 DP ly DP HIGH INPUT 1 Step 7 Determine the Driving Input which must be less than the 4 45 capability of the BE1 87T HIGH T 22 0 Choosing the 2 0 setting for the minimum inputs will yield maximum sensitivity Step 8 Determine the Desired Tap TERTIARY 18 22 A 6 03 Step 9 Select taps by rounding Tp to the nearest tenth HIGH TERTIARY T 2 0 T 6 0 4 36 BE1 87T Installation LOW T 8 2 0 2 50 LOW 2 5 9171300990 Rev Step 10 Determine the CT mismatch My HIGH LOW HIGH TERTIARY LOW TERTIARY My 100 MN 100 Sie of above the smaller of dc above Mat the m of above 6 04 18 22 18 22 6 0 100 753 AG 100 oo s 100 Gaz Gs the smaller of dc above the smaller of FA above the smaller of the above _ 90 9 80 0 80 100 3 02 3 0 100241240 0 80 3 0 2 40 0 0 6 0 4 Step 11 Determine the total misma
70. eipt of a relay check the model and Style Number against the requisition and packing list to see that they agree Visually inspect the relay for damage that may have occurred during shipment If there is evidence of damage immediately file a claim with the carrier and notify the Regional Sales Office or contact a sales representative at Basler Electric Highland Illinois In the event the relay is not to be installed immediately store the relay in its original shipping carton in a moisture and dust free environment For more information see STORAGE in Section 4 When the relay is to be placed in service it is recommended that the VERIFICATION TESTS shown in Section 5 be performed prior to installation RELAY OPERATING PRECAUTIONS Before installation or operation of the relay note the following precautions 1 A minimum of 0 2 A in the output circuit is required to ensure operation of current operated targets 2 The relay is a solid state device and has been type tested in accordance with the requirements defined under Dielectric Test If a wiring insulation test is required on the panel assembly in which the relay is to be installed it is suggested that the connection plugs or paddles of the relay be removed and the cradle withdrawn from the case so as not to produce false readings during the wiring insulation test 3 When the connection plugs are removed the relay is disconnected from the operating circuit and will not provi
71. ency and then add the required harmonic Step 3 Step 4 Step 5 Step 6 Step 7 Apply 2 0 A at 50 or 60 Hz as appropriate for the style to Input 1 The REST TRIP LED should be illuminated Increase the second harmonic current until the REST TRIP LED extinguishes indicating that the inhibit point has been reached Note the magnitude of the second harmonic component at the inhibit point To calculate the second harmonic inhibit percentage divide the second harmonic current measured in Step 4 by the current applied in Step 3 Divide the harmonic current by the fundamental current Factory setting is 12 0 3 for single phase units and 18 0 3 for three phase units Three Phase Units Only Repeat Steps 1 through 5 for phase B terminals 12 amp 13 and phase C terminals 14 amp 13 Three Phase Units Only Upon completion of above testing return the three calibrate toggle switches S2 letter D of Figure 2 4 to the NORM position Fifth Harmonic Restraint Verification Step 1 Step 2 Step 3 Step 4 Step 5 5 12 Set the INPUT 1 tap switches to the 2 0 A position Connect the relay as appropriate refer to Figures 5 2 through 5 5 using terminals 11 amp 13 Input 1 for both single phase and three phase Apply 2 0 A at 50 or 60 Hz as appropriate for the style to Input 1 The REST TRIP LED should be illuminated Increase the fifth harmonic current until the REST TRIP LED extinguishes in
72. es not respond Connect Input 1 current to terminals C and N Connect Input 2 current to terminals N and A This verifies the A and C phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The B phase differential circuit sees no current and does not respond Connect Input 1 current to terminals B and N Connect Input 2 current to terminals N and C 9171300990 Rev R BE1 87T Test Procedures 5 23 This verifies the B and C phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The A phase differential circuit sees no current and does not respond 5 24 BE1 87T Test Procedures 9171300990 Rev R SECTION 6 DIFFERENCE DATA GENERAL This section provides the information necessary to support BE1 87T Transformer Differential Relays with sensing input type F three phases three inputs each phase Sensing input type F relays have a style number with the first character F refer to Style Number Identification Chart Figure 6 1 Sensing input type F relays require the lower connection plug to be removed before the upper connection plug This procedure prevents false trips During installation the lower connection plug should be installed last DIFFERENCES Revision P to BE1 87T relays made sensing input type F obsolete and created sen
73. ests Do not apply power at this time Observing the precautions provided in Section 4 HELAY DISSASSEMBLY remove the relay from its case Then remove the front panel to gain access to the printed circuit boards Remove the Analog 1 board one per phase as shown in Figure 4 19 Connect the Input Grounding jumpers to the disabled position Refer to Figure 4 20 for relays with Option 1 0 and Figure 4 21 for relays with Option 1 1 for correct positioning For further information see Grounding Unused Inputs in Section 4 After testing is complete and prior to placing the relay in service it may be necessary to reposition the jumpers Three Phase Units Only Check that all of the 30 Phase Shift Compensation jumpers on the Analog Board 2 shown in Figure 4 27 are in the WYE position If not reposition these jumpers accordingly NOTE It is possible to test three phase units without changing the 30 Phase Shift Compensation jumpers from the in service positions Refer to Testing Three Phase Step 5 Step 6 Step 7 Step 8 Relays without Changing Jumpers at the end of this section Replace all circuit boards and reassemble the relay Refer to Table 1 1 and Figure 1 2 for multiples of tap and percentage restraint characteristics Set the RESTRAINED PICKUP LEVEL switches and the INPUT 1 and INPUT 2 tap switches to the values shown in Table 5 1 Apply power to the relay Apply input current as indicated in Table 5 1 for
74. etup illustration was added Miscellaneous editing B 03 91 Manual with the exception of Section 2 was rewritten for ease of use A 06 90 Figure 3 1 Functional Block Diagram corrected Formula in caution note formerly on p 4 17 now on p 5 2 corrected Miscellaneous editing 9171300990 Rev R BE1 87T Introduction This page intentionally left blank vi BE1 87T Introduction 9171300990 Rev R CONTENTS SECTION 1 e GENERAL INFORMATION U 1 1 INTRODUCTION etr attente u la h B aita ah awha uy phe date 1 1 DESCRIPTION EE 1 1 6 tereti u uh thats a ta aku uyu ata tea Whats 1 2 single Ph se wie mau hte ayu d een baa al 1 2 TMreG PhaSe a tel e Td e Eae beer ee kaa 1 2 Percentage Ftestralnt eo ed e SRL te fro der p care e ul 1 2 Second Harmonic Restraint ic udo a e Eee eed e t LO Pede 1 2 Fifth Elarmonic Restralbt s eroe UT et ea eaten antes 1 3 Unrestrained Tip eie n eee hav ieee ede 1 3 Me cc ERU 1 3 Push To Energize Output 0 a 1 3 Auxiliary Output Contacts reete ei 1 3 Aiea tess tte t oe b uD aol 1 3 MODEL AND STYLE
75. h jumper can be shifted 30 30 or 0 a total of 60 is achievable between two inputs for special applications In this way the appropriate direction of phase shift can be matched to the shift in the protected transformer This alleviates the need for an extra set of external CTs in most applications Figures 4 28 through 4 32 illustrate the use of internal phase shift in lieu of matching by external CT connections These are typical of the many combinations that can occur 4 24 BE1 87T Installation 9171300990 Rev R CAUTION Assigning 30 Phase Shift Compensation requires disassembly of the relay and must be done when the relay has been taken out of service Access to the 30 Phase Shift jumpers requires the removal of the Analog 2 Board shown in Figure 4 27 To avoid personal injury or equipment damage do NOT proceed unless thoroughly familiar with the instructions in the sections on RELAY OPERATING PRECAUTIONS and RELAY DISASSEMBLY Precautions 30 Phase Shift Compensation Adjustment Procedure The position of a set of movable jumpers on Analog Board 2 determines the state of the internal compensation To gain access to these jumpers it is necessary to remove Analog Board 2 Refer to the topic RELAY DISASSEMBLY for instructions on gaining access to the circuit board then adjust the jumpers shown in Figure 4 27 as follows In cases where no phase shift is wanted all three jumpers A 6B and C shown in Figure 4
76. hases one 240 Vac i two inputs unrestrained NOTES each phase OPTION 2 1 All relays are an M1 size case F eee SUN N Output type must be E and Option 3 must be each phase None S Push to Sensing input type must be E and Option 3 must energize output be O When targets are specified a Two targets are supplied in single phase IN i i SENSING INPUT TIMING styles restrained unrestrained b Five targets are supplied 3 phase styles RANGE jai oe and unrestrained plus phase A B 1 20 H 8 9 A Auxiliary contacts are only available if 2 Sensing Input is not F and Output is E 2 0 4 1 78A D422 003 PAS 50 Hz Figure 6 1 Style Number Identification Chart BE1 87T Difference Data 9171300990 Rev R Figure 6 2 Typical Internal Connections Three Phase Sensing Input Type F Output Option E 9171300990 Rev R BE1 87T Difference Data 6 3 Figure 6 3 Case Terminals Sensing Input Type F Output Option E 6 4 Figure 6 4 Test Setup Sensing Input Type F Output Option E BE1 87T Difference Data 9171300990 Rev R APPENDIX A SETTING NOTES INTRODUCTION These setting notes are to clarify several of the settings steps in Section 4 nstallation SETTING NOTE 1 The procedure outlined in Step 1 assumes that 5 or S is zero and yields the correct magnitude and ratios This note is to point out that the relay taps are determined by the windings turn ratios The use of
77. i L 3 69 93 7 4 16 105 6 2 28 s 57 9 6 20 157 6 E 1 75 a 1 75 44 5 44 5 741 4 188 1 56 14 3 DIA 5 PLACES 50 Le 12 7 TYP 9 Z Y 69 147 17 5 37 3 XB i L 8 L 6 gt 1 75 19 1 DIA 1 00 25 20 PLACES 25 4 6 4 2 63 66 8 D1427 12b 05 29 02 em 5 25 133 4 NOTES N OPTIONAL RECTANGULAR CUTOUT MAY REPLACE 10 DRILLED HOLES 2 TERMINAL NUMBERS SHOWN ARE VIEWED FROM REAR OF RELAY 3 TOP HALF OF PANEL DRILLING DIAGRAM FROM CENTERLINE UP IS SHOWN IN FIGURE 4 6a Inches Millimeters Figure 4 6b Panel Drilling Diagram Bottom Half Projection Mounting 4 8 BE1 87T Installation 9171300990 Rev R DIELECTRIC TEST In accordance with IEC 255 5 and ANSI IEEE C37 90 1989 one minute dielectric high potential tests may be performed as follows All circuits to ground 2121 Vdc Input to output circuits 1500 Vac or 2121 Vdc Note that this device employs decoupling capacitors to ground at all the output terminals and at the power supply terminals 3 4 Accordingly a leakage current of approximately 15 milliamperes per 1000 Vac is to be expected CONNECTIONS Incorrect wiring may result in damage to the relay Be sure to check the model and Style Number against the options listed in the Style Number Identification Chart Figure 1 1 before connecting and energizing a particular relay NOTE Be sure the rela
78. indicating overexcitation of the transformer or when the second harmonic content exceeds 12 single phase or 18 three phase of the operate current indicating a magnetic inrush condition an inhibit signal is developed that blocks operation of the Restrained Trip output contact Stated percentages represent the factory setting Unrestrained Trip Output Iop is also compared against a reference established by the front panel UNRESTRAINED PICKUP LEVEL switch is shown in Figures 2 1 through 2 5 When this reference is exceeded the Unrestrained Trip output relay is energized An unrestrained trip is not affected by through current or harmonic inhibits 9171300990 Rev R BE1 87T Functional Description 3 3 Auxiliary Relay Option Auxiliary relays Option 3 1 3 2 or 3 5 in the tenth position of the Style Number are accompanied by two switches S1 and S2 which allow the relays to respond to a restrained trip S1 ON or to an unrestrained trip S2 ON or both 81 and S2 ON These switches letter of Figure 2 4 and described in Table 2 1 are located on the mother board and are shipped in the ON position Auxiliary relays may be disabled by opening both switches 1 S2 OFF Power Supply Relay operating power is developed by a wide range isolated low burden switching power supply that delivers 12 Vdc to the relay s internal circuitry The power supply is not sensitive to the input power polarity A front panel LED power indicato
79. input current at the maximum external line ground fault level in secondary amperes The input with the least minimum current CT primary current in amperes Relay input current in amperes CT secondary current in amperes Rated self cooled current of the power transformer in multiples of tap Current mismatch with power transformer on its neutral tap Multiple rating CT i e a tapped CT Total mismatch including the maximum transformer tap excursion Total number of CT turns available Number of CT turns in use One way lead resistance in ohms CT winding resistance in ohms Relay resistance in ohms Restrained slope setting from 15 to 60 Saturation factor which equals Vz Vcr Relay current tap 0 4 to 1 78 for 1 ACT 2 to 8 9 for Desired tap based on the current ratio The larger of Vs The CT burden voltage with Zr flowing The CT burden voltage with Zrc flowing Base accuracy class CT voltage rating Accuracy class CT effective voltage where not all turns are used which equals Vc NA N Unrestrained pickup setting in multiples of tap 6 to 21 4 34 BE1 87T Installation 9171300990 Rev R WYE 3 600 5MR 345 kV HIGH 4 ane WYE 3 SIDE 2 y 3360 3 2 3375 A 1 2 12 13 2 2000 5MR 138 kV 1200 5T PA X LOW SIDE 3000 5 _ gt TERTIARY 1 8400 A 3 2 9000 A 1 2 13 280 A 3 12 12 WYE 3 1 87 D240 004 02 12 98 10 LTC 11 Figure 4 33
80. l circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The A phase differential circuit sees no current and does not respond Jumper Positions A1 A1 Step 1 Step 2 Step 3 5 22 Connect Input 1 current to terminals A and N Connect Input 2 current to terminals A and N This verifies the A and B phase differential circuits which respond together The C phase differential circuit sees no current and does not respond Connect Input 1 current to terminals B and N Connect Input 2 current to terminals B and N This verifies the B and C phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The A phase differential circuit sees no current and does not respond Connect Input 1 current to terminals C and N Connect Input 2 current to terminals C and N BE1 87T Test Procedures 9171300990 Rev R This verifies the A and C phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The B phase differential circuit sees no current and does not respond NOTE The same test connections are used for A1 A1 and A2 A2 The proper jumper position is confirmed by which relay differential circuits respond for the specific condition Jumper Positions A2 A2
81. lectrical characteristics and operational features included in BE1 87T relays For example if the Style Number were G1E A1Y D1SOF the device would have the following BE1 87T Model Number designates the relay as a Basler Electric Class 100 Transformer Differential Relay G Three phase sensing with three inputs per phase 1 2 0 to 8 9 A Sensing Range at 60 Hz E One unrestrained output contact and one restrained output contact A1 No intentional delay in the outputs Y 48 125 Vdc switchable D Current operated targets 1 Percent lop display and high speed trip S Push to Energize outputs 0 No auxiliary output F Semi flush mounting STYLE NUMBER IDENTIFICATION CHART 1 87 Al 1 MODEL NO TENES POWER ul UTU E TARGET N OPTION 1 OPTION 3 AN OPTION 4 A Single phase Two NO J 125 Vde amp N None 0 None 0 None F Semi Flush two inputs contacts one 100 120 C Internally 1 Auxiliar Mountin 1205 1 Percent lop y ME B Single phase restrained one Vac operated contacts NO P Projection Display and SOCTS ject three inputs unrestrained K 48 Vdc targets High d 2 Auxiliary Mounting Single phase F Four NO L 24 Vde D Current Spes contacts NC four inputs contacts one Y 48 125 ope
82. lel with 150 Increase until the REST TRIP LED extinguishes The inhibit percentage is l AN 100 x 47 at the point where the LED extinguishes 50 Expected Values 12 3 for single phase 18 3 for three phase For 60 Hz Units Holding the 60 Hz current constant at tap value add a 120 Hz J 29 current in parallel with 160 Increase 7 until the REST TRIP LED extinguishes The inhibit percentage is ere 100 x p at the point where the LED extinguishes 60 Expected Values 12 3 for Single Phase 18 3 for Three Phase Fifth Harmonic Inhibit Step 8 Step 9 For 50 and 60 Hz Units Apply tap value 1 pu to Input 1 REST TRIP LED should be illuminated For Three Phase Units Return S2 to the NORMAL position For 50 Hz Units Holding the 50 Hz current constant at tap value add a 250 Hz 1 current parallel with 150 Increase 1 until the REST TRIP LED extinguishes The inhibit percentage is Iso A 100 x um at the point where the LED extinguishes 50 Expected Values 35 3 for single phase or three phase units For 60 Hz Units Holding the 60 Hz current constant at tap value add a 300 Hz Izo current in parallel with 160 Increase 1 until the REST TRIP LED extinguishes The inhibit percentage is I300 mm 100 x at the point where the LED extinguishes 60 Expected Values 35 3 for single phase or three phase units TESTING THREE PHASE UNITS WITHOUT CHANGING JUMPERS The simp
83. lest way to test three phase units using only two test currents is to set all jumpers to the WYE position Then each comparison circuit is tested independently when the respective phase currents are applied This is not acceptable from two points of view Requires changing the relay settings jumpers from the in service position Does not verify that the jumpers have been properly set It is possible to completely test the BE1 87T with the jumpers set to the in service position and still use only two input current sources When the jumpers are in the positions shown in Table 5 9 the respective current inputs are compared 5 20 BE1 87T Test Procedures 9171300990 Rev R Table 5 9 Input Signals to Comparison Circuits Based On Jumper Positions Cin Jumper s Am The following connections can be used to verify proper relay jumper positions on a three phase unit or to test an in service relay without changing the jumpers These tests only require two input current sources 180 out of phase In most cases the specified input pair will properly test only two of the three phases within the relay In order to test all three of the relay phases two of the three connection pairings should be tested This confirms relay operation Jumper Positions WYE WYE Step 1 Connect Input 1 current to terminals A and B Connect Input 2 current to terminals A and B This verifies the A and B phase differential circuits which respond
84. ll the tap switches Table 5 6 Input Verification 1 A 50 or 60 Hz Tapt Position Input Current Range at Pickup 0 78 0 24 0 31 A 1 28 0 40 0 49 A 1 56 0 49 0 60 A Pickup occurs at 0 35 x Tap See Figure 1 2 T setting of the upper and lower INPUT switches of the input being tested Reference Figures 2 1 to 2 4 Unrestrained Pickup Verification Step 1 Set the INPUT 1 tap switches to the 2 0 A position Connect the relay as appropriate refer to Figures 5 2 through 5 5 as appropriate using terminals 11 amp 13 Input 1 for both single phase and three phase units Step 2 Set the UNRESTRAINED PICKUP LEVEL switch to position A 6 X TAP Increase the input current until the UNREST TRIP LED lights disregard the REST TRIP LED This should occur at 2 4 A 3 as indicated in Table 5 7 Step 3 Repeat Step 2 using the other UNRESTRAINED PICKUP LEVEL switch positions given in Table 5 7 Step 4 For Three Phase Units Only Repeat Steps 1 through for Phase B of input 1 terminals 12 amp 13 and Phase C of input 1 terminals 14 amp 13 Table 5 7 Unrestrained Pickup Verification 1 A 50 or 60 Hz Unrestrained Input 1 Tap Input Current at Pickup Level Position Pickup 396 AIGXTAP J 14 X TAP 5 6A S 21 X TAP 84 Second Harmonic Restraint Verification Step 1 Set the INPUT 1 tap switches to the 0 4 A position Connect the relay as refer to Figures 5 2 through 5 5 as appropriate
85. ll operate at minimum pickup 0 35 times BE1 87T Controls and Indicators 9171300990 Rev R M S Indicator RN Percent of Trip Pushbutton OF TRIP Indicators Option Red LED lights when the OF TRIP pushbutton P is pressed and the restraint current is above the slope characteristic kneepoint as defined in Table 1 1 That is the relay will operate based on the restraint characteristic Pushbutton that is used to activate the of TRIP LEDs When the OF TRIP pushbutton P is pushed eight LEDs shown in Figure 2 5 are used to indicate the approximate percentage of operating current to Minimum pickup LED M also lights or Slope characteristic pickup LED S also lights The eight LEDs represent the following approximate percentages 1LED 3 Yellow LED 2 LEDs 7 Yellow LED 3 LEDs 11 Yellow LED 4 LEDs 20 Red LED 5 LEDs 40 Red LED 6 LEDs 6096 Red LED 7 LEDs 8096 Red LED 8 LEDs 100 Red LED A bar chart above the LEDs shows the relative percentage of trip 9171300990 Rev R BE1 87T Controls and Indicators 2 3 ES Basler Electric INPUT 1 INPUT 2 INPUT 3 1 00 1 60 1 00 1 60 1 00 1 60 See Fig 2 4 UNREST TRIP PHASE A THRU CURRENT UNREST TRIP PHASE B UNREST L TRIP See Fig 2 4 BE1 87T lt TRANSFORMER DIFFERENTIAL POWER W Style No G4E 1 DOSOF
86. margin with respect to the characteristic kneepoint of the BE1 87T Refer to Figure 4 34 lop 1 U L 1 L E S o TOTAL MISMATCH F T EXCITING CURRENT MAXIMUM Ig IN MULTIPLES OF TAP BE1 87T D610 010 3 2 91 Figure 4 34 Slope Needed to Accommodate Total Mismatch with Adequate Margin Specifically if the maximum saturation factor Sp from Step 16 exceeds 0 5 set the RESTRAINED PICKUP LEVEL to setting K which is equal to 60 as shown in the table on the front panel For all other cases including this example use the following equation Where S restrained slope setting Mr total mismatch in percent Ir rated self cooled current of the power transformer in multiples of tap For a three winding transformer application such as this example the maximum of the three values of M and of I is used Mrz is 10 6 from Step 11 and ris 2 42 Step 20 BE1 87T Installation 9171300990 Rev R 35 10 6 3 23 4 2 42 38 8 Because the maximum saturation factor Sp for this example is less than 0 5 from Step 16 use the next highest slope Select position F which 40 For examples of suitable slope settings see Table 4 2 Table 4 2 Examples of Suitable Slope Settings Maximum Current Rating of Power Recommended Minimum Mismatch in 96 Transformer in RESTRAINED PICKUP Multiples of LEVEL Seiting Slope 53 Sr V B V ce If Sr gt 0 5 set the RESTRAINED PICKUP LE
87. nce It corresponds to an excitation voltage on a curve passing through point Q in Figure 2 at which the excitation current is 10 amperes the maximum error allowed by the accuracy class definition The Rsx100 term represents the voltage drop across the CT internal resistance A new SF which takes the internal CT resistance into account can be defined on the excitation curve as peer VIO Where Ve is the internal excitation voltage VT Rs IF at the maximum fault current IF and V10 is the voltage of the curve passing through point Q where the exciting is 10A This voltage is practically close to the knee point voltage which would yield nearly the same a slightly more conservative result Since in all likelihood the excitation voltage capability of the CT will be higher passing through point R in Figure 2 for instance the saturation factor defined on the excitation curve appears to be lower i e more favorable A detailed analysis can be performed to compare the two saturation factor definitions Saturation Factor Definitions Compared Using the equivalent circuit in Figure 1 and the ANSI Accuracy Class definition that the CT must be able to source 20 times nominal current into a standard burden Zc we now develop a comparative analysis between the two definitions SF ME Ve VC V10 ZB IF pe gp IFAZB 5 100 Zc 100 Zc Rs A 8 BE1 87T Setting Notes 9171300990 Rev R To compare the two expressions we
88. nel Refer to Figure 2 1 through 2 4 for location Appropriate power must be applied to Power Supply terminals 3 and 4 shown in Figures 4 7 through 4 10 for these pushbuttons to operate the output relays However it is not necessary to apply currents to the sensing inputs of the relay for these switches to function Auxiliary Output Contacts Three types of auxiliary output contacts are available Normally open normally closed and SPDT The contacts can be made to respond to a restrained trip an unrestrained trip or both Refer to the Functional Description Auxiliary Relay Option for further information Power Supply Various power supply options are available to allow the BE1 87T to be used with standard supply voltages See the Style Number Identification Chart Figure 1 1 for details 9171300990 Rev R BE1 87T General Information 1 3 MODEL AND STYLE NUMBER The electrical characteristics and operational features of the BE1 87T Transformer Differential Relay are defined by a combination of letters and numbers that make up its Style Number The Model Number together with the Style Number describe the options included in a specific device and appear on the front panel drawout cradle and inside the case assembly Upon receipt of a relay be sure to check the Style Number against the requisition and the packing list to ensure that they agree Style Number Example The Style Number Identification Chart Figure 1 1 defines the e
89. nene 5 15 nnne nennt 5 16 Second Harmonic Restraint Verification sess 5 16 Fifth Harmonic Restraint 9 5 17 Response Time 5 18 OPERATIONAL TEST PROCEDURES 5 19 Restrained PICKUP s cucurrit arcs ae ved eee ee ada Pee ae 5 19 Sacris S 5 19 Second Harmonic Inhibit u uu kai didan aasi iaiia inani Kadi 5 19 Inhibib ient eti ertet ir eed eec tete ees i re qaq n ck e pna 5 20 TESTING THREE PHASE UNITS WITHOUT CHANGING 5 20 Jumper Positions Wye Wye Aae EEEE E VAS 5 21 Jumper Positions 5 21 Jumper Positions Wy Dellag2 5 22 Jumper Positions 1 1 5 22 Jumper Positions 2 2 nnns nnn ens 5 23 Jumper Positions 1 2 2 22 1 0 000 nennen nennen nnne nennen 5 23 viii BE1 87T Intr
90. ng during initial energization and external fault conditions A through current restraint also provides security against tripping for external faults An unrestrained tripping element is included to provide a high speed trip in the event of a particularly severe fault within the transformer DESCRIPTION The functional block diagrams of Figures 3 1 and 3 2 illustrate the overall operation of the BE1 87T Transformer Differential Relay Figure 3 1 shows Phase A or single phase functions Figure 3 2 shows the additional functions for phases B and C Since the three phases are functionally similar only phase A is shown in detail in Figure 3 1 Note that in a three phase unit there may be one restrained output for each phase Output Type Option E in the third position of the Style Number or one restrained output that serves for all three phases Option F in the third position When Target Option C or D is specified for a three phase Unit in the seventh position an individual target is supplied for each phase Current Transformers In the protected zone of the power system CTs with a 1 ampere or 5 ampere secondary winding supply the sensing current for each input This is not shown in Figure 3 1 or Figure 3 2 Other relays may be connected ahead of the BE1 87T Sensing currents are in turn applied to relay internal input transformers These transformers provide system isolation Scaling Input currents are scaled by the front panel INPUT r
91. nsformer overexcitation causes additional exciting current to flow into one set of terminals This presents an apparent differential or operating current not attributable to an internal fault Although potentially damaging overexcitation is not an internal fault and therefore is not an appropriate condition for transformer differential relay operation One of the principal components in the complex waveform produced during overexcitation is the fifth harmonic BE1 87T relays use fifth harmonic restraint to inhibit the differential relay operation Unrestrained Trip Severe internal transformer faults may cause CT saturation Under such circumstances harmonic restraint transformer differential relays may fail to trip because of the extremely high harmonic content in the waveform Lack of operation can result in severe transformer damage BE1 87T relays provide an independent unrestrained tripping function When set above the possible inrush current magnitude this function provides high speed protection for the most severe internal faults OPTIONS Push To Energize Output Pushbuttons Two PUSH TO ENERGIZE OUTPUT switches are available as a means to verify external output wiring without the inconvenience of having to test the entire relay Option 2 S provides a small pushbutton switch for each isolated output function Restrained and Unrestrained and may be actuated by inserting a thin non conducting rod through access holes in the front pa
92. nt That input is chosen and then called the Imax signal The 4x output is then scaled by the front panel RESTRAINED PICKUP LEVEL switches shown as the Hestrained Pickup Control in Figure 3 1 The resulting signal Ivax that represents the percentage of through current is extended to the Then Trip comparator and the 7o Divided By Ivax function The Then Trip circuitry compares the operating current to Ivax If the operating current is greater than Ivax and there is no 5th or 2nd harmonic restraint to cause an inhibit as described below a Restrained Trip output is produced Divided By Ivax contains eight comparators and compares to the preset percentage levels of lmax Mf Top is greater than the preset percent of 1 for a specific comparator the LED associated with that comparator lights The eight LEDs represent the following approximate percentages First LED 3 SecondLED 7 Third LED 1196 Fourth LED 2096 Fifth LED 40 Sixth LED 60 Seventh LED 8096 Eighth LED 100 NOTE As each successive LED lights all previous or lesser percentage value LEDs will also light Harmonic Restraints Development of a restrained trip output may be inhibited by either of two harmonic restraints These are generated by bandpass filters tuned to the second and fifth harmonics of the operating current Comparators monitor these signals When the fifth harmonic content exceeds 35 of the operate current
93. oduction 9171300990 Rev R SECTION 6 e DIFFERENCE DATA U U U U U U nananana 6 1 ejr 6 1 DIERERENGES etiem eie tamia t Ed ere ect tid fea reed he yma i 6 1 COMPALTIBIEETY ete ett ec ettet ec esta cotes Ud e o eura 6 1 Tx 6 1 APPENDIX A e SETTING NOTES 222222201 uu u cR RR Ra u A 1 INTRODUCTION Cm 1 oii zac Imm A 1 SETIFINGNOTE2 mm 2 SEWING NOTE ERR A 3 SEATING NO TE 55 aAA aA A 4 SANNER O TE 5 E AE E AEE A AE ET A 4 Slope Margil 25 556 ole c tem aa a E end e suit Yanta a e at A 4 SETTING N TE a EAEE S A A AE a TAE AE A EEA EEA A 6 Inrush vs Unrestraint Tap rtr EE AKRA E EIEEE A 6 EER AE E l Sa A E AEA A 7 CT Performance Evaluation Saturation A 7 Saturation Factor Defined from the ANSI C Classification A 7 Saturation Factor Defined from the CT Excitation Curve A 8 Saturation Factor Definitions Compared U aS A 8 GODCIUSIOD E FE IE E OE EPOR ETUR
94. of controls that are mounted inside the relay call out letters B D and 1 are shown in Figure 2 4 Table 2 1 Controls and Indicators INPUT or TAP Switches Front panel INPUT switches are used to scale the transformer currents There are two of these rotary switches for each input 1 Ampere CT Units Each of the upper switches is calibrated to represent the tenths and units digits 0 4 through 1 6 of tap value Each of the lower switches is calibrated to represent two hundredths of tap value for each increment Always add the setting of the lower switch to that of the upper switch For example if a setting of 1 02 is desired the upper switch must be at 1 0 and the lower switch must be at 0 02 The total setting range for each input is 0 4 to 1 78 5 Ampere CT Units Each of the upper switches is calibrated to represent the units digit 2 through 8 of tap value Each of the lower switches is calibrated to represent tenths of tap value Always add the setting of the lower switch to that of the upper switch For example if a setting of 5 0 is desired the upper switch is set to 5 0 the lower switch must be at 0 0 The total setting range for each input is 2 0 to 8 9 three phase units ONLY relay either 30 30 or 0 depending upon the position of the jumpers provided for each input on the Analog 2 Board shown in Figure 2 4 Additional information is in Section 4 UNRESTRAINED PICKUP This thumbwheel switch establishes the
95. otary switches that introduce resistances to the internal CT secondaries The switches are calibrated in 0 02 ampere increments from 0 4 to 1 78 ampere for 1 ampere CT units Options 2 or 4 in the second position of the Style Number and in 0 1 ampere increments from 2 0 to 8 9 amperes for 5 ampere CT models Options 1 or 3 in the second The many graduations of adjustment are provided to allow each input to approach an ideal representation of the actual operating per unit value Summing Analog signals representing each input contribution are vector summed shown as Summing in Figure 3 1 This summing process produces the operating current that is the phasor sum of the input currents Ideally and with perfectly matched CTs a transformer without an internal fault should cause Io to be exactly zero on a continuous basis When not zero a fault would be indicated However saturation effects caused by heavy through current or magnetic inrush can cause a temporary imbalance even though no internal fault has occurred To prevent a false trip under such conditions various types of restraint are used Each restraint is specific to a potential cause of misoperation These are individually discussed in the topic Restrained Trip Output 30 Internal Phase Shift Three Phase Relays ONLY For three phase units the inputs to the Summing function are first routed through the 30 Phase Shift circuit There the signals may be advanced or retarde
96. phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The B phase differential circuit sees no current and does not respond Connect Input 1 current to terminals B and C Connect Input 2 current to terminals B and N This verifies the B and C phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The A phase differential circuit sees no current and does not respond Jumper Positions WYE A2 Step 1 Step 2 Step 3 Connect Input 1 current to terminals A and B Connect Input 2 current to terminals N and B This verifies the A and B phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The C phase differential circuit sees no current and does not respond Connect Input 1 current to terminals A and C Connect Input 2 current to terminals A and N This verifies the A and C phase differential circuits which respond together as provided earlier in the Verification Tests 5 Amp CT or Verification Tests 1 Amp CT in this section The B phase differential circuit sees no current and does not respond Connect Input 1 current to terminals B and C Connect Input 2 current to terminals N and C This verifies the B and C phase differentia
97. pickup tests always decrease one current starting from a balanced input Since percentage restraint is derived from the maximum current at any one input an increase of any current increases restraint By contrast a decrease of one current has no effect on restraint Step 1 Connect the relay as appropriate refer to Figures 5 2 through 5 5 Apply the tap value to Input 1 and to Input 2 Step 2 With Input 1 constant decrease Input 2 until the REST TRIP LED lights Ensure that this measurement is within 6 of the calculated current Return Input 2 to tap value Step 3 With Input 2 constant decrease Input 1 until the REST TRIP LED lights Ensure that this measurement is within 6 of the calculated current Return Input 1 to tap value Unrestrained Pickup Step 4 Set the front panel UNREST PICKUP LEVEL switch to the desired multiple of the tap setting X TAP which is the pickup level Step 5 Increase the input test current until the UNREST TRIP LED lights Ensure that this measurement is within 3 of calculated pickup Do NOT exceed the thermal rating Second Harmonic Inhibit Step 6 For 50 and 60 Hz Units Apply tap value 1 pu to Input 1 The REST TRIP LED should be illuminated For Three Phase Units Set CALIBRATE switch S2 to CAL Position see Figure 2 4 9171300990 Rev R BE1 87T Test Procedures 5 19 Step 7 For 50 Hz Units Holding the 50 Hz current constant at tap value add a 100 Hz current in paral
98. r lights to indicate that the power supply is functioning properly Style number designations and input voltage ranges for the available power supply models are provided in Section 1 General Information Power Supply Status Output Optional The Power Supply Status output relay has normally closed NC contacts The relay is energized by the presence of nominal voltage at the output of the power supply Normal operating voltage then keeps the relay continuously energized and its contacts open However if the power supply voltage falls below requirements the Power Supply Status output relay will de energize and close the contacts The Power Supply Status output is not associated with any magnetically latched target The POWER LED on the front panel provides a visual indication of the normal operating status of the power supply NOTE Sensing Input Types A through E first position of the Style Number have paddle operated shorting bars included in the relay case terminals 19 and 20 so that the Power Supply Status output terminals can provide a remote indication that the BE1 87T has been withdrawn from its case or that it has been taken out of service by removing the connection plugs Sensing Input Type G relays do NOT have shorting bars on the Power Supply Status output Sensing Input Type G units use terminal 9 lower terminal block and terminal 19 upper terminal block for the Power Supply Status output Target Indicators Optional
99. r the wye winding and in wye for the delta winding This type of connection also eliminates the zero sequence component of current which could cause a false trip operation during external ground fault conditions on the wye system Three Phase BE1 87T Three Phase relays can provide zero sequence filtering and compensation for phase shifts introduced by the connections of the power transformer This 30 Phase Shift compensation either 30 or no compensation is field selectable Additionally this feature allows sharing the transformer differential relay CTs with other relays or instrumentation BE1 87T relays use the highest input current in per unit values to operate on maximum restraint The relay does not have a conventional operate winding in the internal magnetics Operating current is developed within the electronics of the relay Percentage Restraint A primary concern in differential relay applications is security against high current levels caused by faults outside the protected zone Inevitable differences in the saturation characteristics between current transformers require a compensating decrease in relay sensitivity It is also necessary to be able to adjust the sensitivity to compensate for transformer voltage taps or CT mismatches This is accomplished by providing a restraint factor proportional to the current flowing through the protected zone through current BE1 87T relays maintain sensitivity at a specified ratio of t
100. rated ne 5 Auxiliary D Single phase restrained for Vdc targets contacts SPDT five inputs each of 3 Z 250 Vdc Three phase phases one 240 Vac two inputs unrestrained each phase G NOTES three inputs h phas each phase 1 All relays are in an 1 size case e a A N Output type must be E and Option 3 must be 0 AN Sensing input type must be E and Option 3 must SENSING INPUT IMS be ORION Z RANGE x NEC When targets are specified A1 Instantaneous a Two targets are supplied in single phase N None 1 2 0 8 9 A styles restrained unrestrained S Push to 60 Hz b Five targets are supplied in 3 phase styles energize output 2 0 4 1 78A restrained and unrestrained plus phase A B 50 Hz and C 3 20 8 9 A A Auxiliary contacts are only available if 50 Hz Sensing Input is not G and Output is E 4 0 4 1 78A 60 Hz 6 This drawing based on 9 1715 50 471 REV F Figure 1 1 Style Number Identification Chart 1 4 BE1 87T General Information 9171300990 Rev R SPECIFICATIONS The BE1 87T relay is available in either single phase or three phase configurations and with the following features and capabilities Current Sensing Inputs Maximum Current Per Input 1 Ampere CT Units 5 Ampere CT Units Current Sensing Burden Tap Setting Control Scaling 1 Ampere CT Units 5 Ampere CT Units Restrained Output Pickup Range Pickup Accuracy Minimum Pickup 9171300990 Rev R
101. re 2 4 to the NORM position Fifth Harmonic Restraint Verification Step 1 Step 2 Step 3 Step 4 Step 5 Set the INPUT 1 tap switches to the 0 4 A position Connect the relay as appropriate refer to Figures 5 2 through 5 5 using terminals 11 amp 13 Input 1 for both single phase and three phase Apply 0 4 A at 50 or 60 Hz as appropriate for the style to Input 1 The REST TRIP LED should be illuminated Increase the fifth harmonic current until the REST TRIP LED extinguishes indicating that the inhibit point has been reached Note the magnitude of the fifth harmonic component at the inhibit point To calculate the fifth harmonic inhibit percentage divide the current measured in Step 3 by the current applied in Step 2 Divide the harmonic current by the fundamental current Factory setting is 35 0 3 for both single phase and three phase styles Three Phase Units Only Repeat Steps 1 through 4 for phase B terminals 12 amp 13 and phase C terminals 14 amp 13 9171300990 Rev R BE1 87T Test Procedures 5 17 Response Time Verification Step 1 Step 2 Step 3 Step 4 Step 5 Step 6 Step 7 Step 8 Step 9 Step 10 5 18 Connect the relay as appropriate refer to Figures 5 2 through 5 5 Set the RESTRAINED PICKUP LEVEL switch phase A to A 15 Place all of the INPUT switches on the 0 4 A tap position Apply 0 4 A at 50 or 60 Hz as appropriate for the style to Inpu
102. rip current to through current This ratio generally referred to as slope is front panel adjustable in 5 96 increments from 15 to 60 96 Second Harmonic Restraint Magnetizing inrush current presents another problem unique to transformer differential relays Relays must be capable of detecting the small differences in current caused by the shorting of a limited number of turns yet remain secure against the occurrence of magnetizing currents many times the transformer rating as seen at one set of terminals Although magnetizing inrush is usually associated with the energizing of the transformer any abrupt change in the energizing voltage may produce this phenomenon Common causes are the transients generated during the onset evolution and removal of external faults Desensitizing the relay only during energization is therefore insufficient 1 2 BE1 87T General Information 9171300990 Rev R Magnetizing inrush produces an offset sine wave rich in all harmonics BE1 87T relays use the second harmonic to restrain operation because it predominates and because it does not occur in significant magnitude or duration at other times Three phase BE1 87T relays use second harmonic sharing The second harmonic content of all three phases is summed together to derive the restraint for each phase As a result the second harmonic inhibit range and the associated factory setting is higher than on single phase relays Fifth Harmonic Restraint Power tra
103. rrent Ist IP RCT is reduced by the excitation current Ie to yield the actual current Is This relationship is illustrated in the CT equivalent circuit shown in Figure 1 Is Rs RI Rr IP Ist VT Figure 1 CT Equivalent Circuit For relaying applications the CT performance is considered acceptable if the ratio correction is less than 10 The ratio error is defined C57 13 1993 Section 8 1 10 as re Is This criterion is expressed in the ANSI C accuracy class which is defined in the following sentence Under steady state symmetrical current conditions the excitation current must be less than 10 amperes for a relay current of 100 amperes into the specified standard burden Since fault currents necessarily start with some degree of transient DC offset good design practice requires that the ratio error remain below 1096 during the initial transient offset period if possible particularly when fast tripping is in effect It has been generally accepted that a design for a saturation factor SF of 0 5 or less is acceptable The following analysis provides two definitions of the saturation factor using a C200 application as an example Saturation Factor Defined from the ANSI C Classification In Figure 2 the CT terminal voltage increases linearly with the secondary current along the V ZBx line where ZB is the total CT burden leads plus relays for a particular fault and connection A
104. s are not UL Recognized for voltages greater than 250 V GOST R Certification Gost R certified No POCC US ME05 B03391 complies with the relevant standards of Gosstandart of Russia Issued by accredited certification body POCC RU 0001 11ME05 Patent Patented in U S 1991 U S Patent No 5014153 Patented in Canada 1993 Shock In standard tests the relay has withstood 15 g in each of three mutually perpendicular axes without structural damage or degradation of performance Vibration In standard tests the relay has withstood 2 g in each of three mutually perpendicular axes swept over the range of 10 to 500 Hz for a total of six sweeps 15 minutes each sweep without structural damage or degradation of performance 9171300990 Rev R BE1 87T General Information 1 9 Operating Temperature Storage Temperature Weight Case Size 40 C 40 F to 70 C 158 F 65 C 85 F to 100 C 212 F 22 3 lbs 10 1 kg maximum three phase unit 19 5 Ibs 8 85 kg maximum single phase unit All units are supplied in an M1 case size See Section 4 Installation for case dimensions BE1 87T General Information 9171300990 Rev R SECTION 2 CONTROLS AND INDICATORS LOCATION OF CONTROLS AND INDICATORS Table 2 1 lists and briefly describes the operator controls and indicators of the BE1 87T Transformer Differential Relay Reference the call out letters A through M to Figures 2 1 to 2 3 N through Q to Figure 2 5 Exploded views
105. s configured with other protective devices it is recommended to use a separate lead to the ground bus for each relay Connections should be made with 14 AWG stranded wire or better except as noted for the ground wire Figure 6 3 shows case terminal designations for sensing input type F relays And Figure 6 4 shows the test setup Refer to the test procedures in Section 4 for testing sensing input type F relays Testing procedures are the same with the exception of terminal connections and the procedures for removing connection plugs 9171300990 Rev R BE1 87T Difference Data 6 1 STYLE NUMBER IDENTIFICATION CHART BE1 87T l A 1 0 MODEL NO POWER OUTPUT SUPPLY TARGET OPTION 1 OPTION 4 Single phase Two J 125 Vde amp N None 0 None 0 None F Semi Flush two inputs contacts one 100 120 C Internally 1 Auxiliary Mounting Single phase restrained one Vac operated contacts NO P Projection three inputs unrestrained K 48 Vde targets 2 Auxiliary Mounting Single phase F Four NO L 24 Vde D Current contacts NC four inputs contacts one Y 48 125 operated 5 Auxiliary D Single phase N restrained for Vde targets contacts SPDT five inputs each of 3 Z 250 Vdc E Three phase p
106. should be observed CAUTION 1 Always remove power from the BE1 87T by removing the connection plugs before removing or installing a printed circuit board 2 Always neutralize static body charge before placing a printed circuit board on or removing one from metal surfaces This can be accomplished by placing your hand on the metal surface before handling the boards 3 Never hand a printed circuit board to another person whose static body charge has not been neutralized 4 Testing or troubleshooting should always be done on a conductive and grounded static controlled surface 5 Never test printed circuit boards with an ohmmeter The test current from the ohmmeter may exceed component ratings 6 Printed circuit boards or integrated circuits should be transported only in electrically conductive containers The use of ordinary plastic bags may result in damage from static charge buildup Circuit Board Removal Procedure Step 1 Remove the front cover and connection plugs CAUTION To prevent possible false tripping the upper connection plug should be in place prior to removing or installing the lower connection plug Step 2 Withdraw the cradle assembly see Figure 4 19 9171300990 Rev R BE1 87T Installation 4 17 Step 3 Remove the four screws that attach the front panel to the cradle assembly and remove the front panel Step 4 With a slight side to side rocking motion withdraw Analog Board 1
107. sing input type G for three phase three inputs for each phase Primary differences between sensing input types F and G are e Sensing input type G relays do not require a specific procedure for removing and installing connection plugs Sensing input type F relays have the normally closed power supply status PSS output at terminals 19 and 20 and have shorting bars across the PSS terminals refer to Figure 6 2 Sensing input type F relays have terminal 9 for the common terminal on restrained and unrestrained outputs Sensing input type G relays have the normally closed PSS output at terminals 9 and 19 and have NO shorting bars across the PSS terminals refer to Figure 4 7 Sensing input type relays have terminal 20 for the common terminal on restrained and unrestrained outputs COMPATIBILITY Revision P relays with sensing input type G are NOT compatible with previous versions of the relays with sensing input type F CONNECTIONS Sensing input type F relays three phase three inputs per phase provide protection for transformers requiring three differential inputs per phase Be sure to check the model and style number against the options listed in the Style Number Identification Chart before connecting and energizing a particular relay NOTE Be sure the relay case is hard wired to earth ground with no smaller than 12 AWG copper wire attached to the ground terminal on the rear of the relay case When the relay i
108. sts The 10 fingers on the black side are connected to the inner binding posts black thumbnuts and tap into the relay internal circuitry The 10 fingers on the red side of the test plug are connected to the outer binding posts red thumbnuts and also connect to the relay case terminals When testing circuits connected to the bottom set of case terminals the test plug is inserted with the numbers 1 through 10 facing up When using the test plug in the upper part of the relay the numbers 11 through 20 are face up It is impossible due to the construction of the test plug to insert it with the wrong orientation 9171300990 Rev R BE1 87T Installation 4 51 This page intentionally left blank 4 52 BE1 87T Installation 9171300990 Rev R SECTION 5 TEST PROCEDURES OVERVIEW BE1 87T Transformer Differential Relays are calibrated and tested for correct operation at the factory and all calibration pots are sealed Immediately upon receipt of the relay or after extended service it is recommended that the Verification Tests provided in this section be performed These comprehensive tests verify all operating parameters including calibration BE1 87T relay Verification Tests are divided into two groups based on the current CT ampere rating and the nominal operating frequency See the first position of the Style Number and the Sensing Input Range Option as shown in Figure 1 1 Five Amperes CT 60 Hz Units Range 1 and Five Amperes CT 50
109. t 1 terminals 11 amp 13 on both single and three phase styles and to Input 2 terminals 12 amp 13 on single phase and terminals 15 amp 18 on three phase Perform a restrained trip at 2 x Pickup by stepping the Input 2 current to 0 68 A Note the time interval between initiation of the simulated fault and the closure of the restrained output contact The trip time should be less than that shown in Table 5 8 Repeat Step 4 at 10 x Pickup Note that with Input 1 at 0 4 A Input 2 current should be stepped to 1 8 A The trip time should be less than that shown in Table 5 8 Three Phase Units Only Repeat Steps 1 through 5 for Phases B and C Place the UNRESTRAINED PICKUP LEVEL switch to the A setting 6 X TAP Place all of the INPUT switches to the 0 4 A tap position With 0 0 A at Input 1 terminals 11 amp 13 apply 4 8 A 2 x Pickup to Input 2 terminals 15 amp 18 on three phase Note the time interval between initiation of the simulated fault and the closure of the unrestrained output contact The interval should be less than that shown in Table 5 8 Repeat Steps 7 and 8 at 10 x Pickup Note that with Input 1 at 0 0 A it will be necessary to step the Input 2 current to 24 A for an unrestrained trip The trip time should be less than that shown in Table 5 8 Three Phase Units Only Repeat Steps 8 and 9 for phases B and C Table 5 8 Timing 1 A 50 or 60 Hz Option 1 0 Option 1 1 Timing Maximum Timing Maxim
110. ta As inputs to a differential relay these currents must be compensated or scaled so that the relay can compare the inputs and determine when an unbalance exists Under ideal operating conditions the scaled vector sum of these currents is zero Because it is practically impossible to match the magnitudes of these detected currents from the various power windings using standard CT ratios the currents are matched within the relay by scaling each of the applied currents by an appropriate factor called a Tap Setting This is set by means of the front panel INPUT dials By selecting suitable tap ratios the applied currents are scaled within the relay to achieve the desired balance for normal operating conditions BE1 87T relays offer a range of available tap settings for inputs between 0 4 A to 1 78 A Sensing Input Range Options 2 and 4 for a 1 ACT or 2 0 to 8 9 A Sensing Input Range Options 1 and for a 5 A CT These settings are independently adjustable in increments of 0 02 A for Sensing Input Range Options 2 and 4 or 0 1 A for Sensing Input Range Options 1 and 3 These small increments allow more precise scaling of the applied currents and usually eliminate the need for installing auxiliary ratio matching CTs Single Phase BE1 87T Single Phase relays require phase angle compensation to be accomplished externally by proper connection of the system CT secondaries A wye delta transformer requires that the CT secondaries be connected in delta fo
111. take the ratio SF SF SF Zc ZB Rs SF ZB Zc Rs Since this expression varies with the ratio of the actual relay circuit burden ZB to the accuracy class burden Zc and the CT internal resistance Rs it is best visualized with a surface plot showing simultaneous variations of the parameters The following example is based on a C200 Zc 2 with Rs varying from 0 1 to 0 8 ohms and ZB varying from 0 1 to 2 times ZC ohms Load angles are neglected Figure 3 SF SF Ratio The 0 to 20 axis represents the variations X10 of ZB 20 is 2xZC The 0 to 8 axis represents the variations x10 of Rs in ohms The vertical axis 0 to 4 shows that for ZB values equal to or greater than the burden value Zc the two saturation factor equations are nearly identical The ANSI Accuracy Class method yields the larger more conservative result For low values of ZB and large values of Rs the Excitation Curve method yields a larger saturation factor Since the Excitation Curve method is closely following the CT characteristics it may be said that the ANSI Class method which neglects the CT internal resistance is too optimistic in this range and should be discarded in favor of the Excitation Curve method The absolute values of SF and SF are compared in Figure 4 for the particular case where Zc 2 ZB 0 5 and Rs 0 8 when IF varies from 0 to 100A SF and SF for Zc 2 ZB 0 5 Rs 0 2 0 4 SFip yp 02 IF Figure 4 Comparing SF and SF 91
112. tch Mr Mn LTC Add the maximum CT mismatch My based on the power transformer in the neutral tap position to the total permissible tap excursion from neutral In this example a 10 load tap change LTC must be accommodated Therefore 0 64 10 10 6 96 Verify CT Performance NOTE This procedure uses the ANSI accuracy class method See Appendix A Setting Note 7 for more information Step 12 Determine the maximum CT secondary fault current for external faults 3 for three phase and for line to ground Refer again to Figure 4 33 for this example The maximum fault current is recorded for each set of terminals for all combinations of external faults HIGH TERTIARY LOW _ 3360 215280 _ 8400 F190 F3 600 240 28 22 35A 3375 9000 eee 0 28 38 A Step 13 Determine the worst case burden voltage for a three phase fault Vas e For wye connected CTs Ir3 R Rp e For delta connected CTs based on a three phase fault refer to Appendix A Setting Note 2 Vgpa Rw 3 3 Where determined in Step 12 p relay resistance in ohms lt 0 05 ohm Ry winding burden R one way lead resistance in ohms 9171300990 Rev R BE1 87T Installation 4 37 Neglecting Rr use R from Figure 4 33 HIGH TERTIARY LOW Vg 28 0 7 Vg 22 0 7 Vg 35 0 7 19 6 15 4 24 5 Step 14 Determine the burden voltage for line to ground fault Vac
113. ted CTs 9171300990 Rev R BE1 87T Setting Notes A 3 SETTING NOTE 4 OAS D2751 18 02 03 98 1 Find the maximum pu fault current for external faults ie 2 Assume that one of the input CTs saturates to 70 3 Set unrestraint pickup gt 7 X IE 1 V Iru Rcu x L R I FH Sct i i FH Top TRIP gt Rm Sie 78 7 A C x UNRESTRAINT M MPU SETTING 0 31 L rn 4 lt 0 3 x IrL T Ro ho t L RccxTL 4 14 02751 19 03 12 98 v Figure A 4 Unrestraint Tap Setting SETTING NOTE 5 Slope Margin The slope formula accounts for an operating current bias due to magnetizing current in one winding The magnetizing current is assumed to be 496 of the OA rating Step 20 is used to scale this magnetizing ratio to the corresponding ratio of relay operate current 4 x 17 The formula further assumes a conservative margin corresponding to an operation current of 2396 of tap The actual margin varies with the tap settings as given by the following equation Margin 35 4x Ir Mr 3 x2 The margin variations for different tap settings 7 can be evaluated with this equation The following plots show the calculated slope and the resulting margin for Mr varying from 1 to 11 and varying from 5 to 2 plot shows 10 x Jr A 4 BE1 87T Setting Notes 9171300990 Rev R D2
114. terminal voltage VT corresponds to the maximum fault current This voltage is lower than the maximum voltage VC that the C200 CT can support Saturation will occur i e ratio error will exceed 1096 for secondary currents in excess of IFs where the corresponding terminal voltage crosses the accuracy class limit VC point C in Figure 2 We can define a measure of the degree of saturation with the saturation factor SF sp IFs By examination of triangles OAB and OCD the same saturation factor can be expressed as sr VL VC 9171300990 Rev R BE1 87T Setting Notes A 7 lt am z 9 2 E LAM PINE REM C400 2 ra Vio a SS Vk mat lo a VK Ve Rs 100 206 VT 10 20 40 IF IFs 100 EXCITATION CURRENT RELAY CURRENT Figure 2 CT Terminal and Excitation Voltages This first definition of saturation relates the CT terminal voltage to the accuracy class of the CT effective class in the case of multi ratio CTs It is practical and easy to calculate since it requires only readily available data An application is considered reasonably secure when SF is less than 0 5 Saturation Factor Defined from the CT Excitation Curve The definition of the saturation factor given above appears to be conservative because it assumes the worst case ratio error However a closer look is required since it neglects the CT internal resista
115. th Option 1 0 Three Input Disabling Jumpers are located on each Analog Board 1 as shown in Figure 4 20 Single Phase Units with Option 1 1 Three additional Input Disabling Jumpers are also located on each Analog Board 1 as shown in Figure 4 21 J9 is a factory adjustment and is not intended to be changed in the field BE1 87T single phase units are shipped with all inputs enabled Three Phase Units Three Phase Units with Option 1 0 Three Input Disabling jumpers are located on each Analog Board 1 as shown in Figure 4 20 Three Phase Units with Option 1 1 Three additional Input Disabling jumpers are also located on each Analog Board 1 as shown in Figure 4 21 J9 is a factory adjustment and is not intended to be changed in the field For Three Phase Units with Input Sensing Type E two inputs per phase The jumpers shown in Figures 4 20 and 4 21 are shipped in the disabled position and no further adjustment should ever be necessary For Three Phase Units with Input Sensing Type G three inputs per phase The jumpers shown in Figures 4 20 and 4 21 are shipped with Input 3 enabled and Inputs 4 and 5 disabled If only two inputs are actually used which must be Inputs 1 and 2 it is important to disable the unused input of each phase by means of the internal Input Disabling jumpers provided on each of the three Analog Boards 1 as shown in either Figure 4 20 or Figure 4 21 J9 in Figure 4 21 is a factory adjustment and is not intended
116. the MVA rating is only a convenient way of calculating the currents i e taps in proportion to their voltage rating It does not mean that the windings will necessarily carry the maximum rating L 5 V3 Vals v I 1 V gt 81 4 3 Vit 3 S3 43 Vals D2751 16 01 30 98 12 2 5 Vili VolIo Vsls Hey 1 Vi _ 5 87 S Winding Rating MVA Figure A 1 Multi winding Transformer 9171300990 Rev R BE1 87T Setting Notes A 1 SETTING NOTE 2 I I Ry NE R A t y ty R L I B R B y x 1 s Ic R D2751 17 01 30 98 14 15 1 0 1 10 1Ga Ic Rg En IA zL RyE Ry RgRFRg Ig Rr Rg Ic Rj Rg L Ry 2R 2Rg IgtIc Ry Rg Since I4 Ig Hc V I Rw 3R 3Rp Where I4 3 Phase fault current Relay burden R Lead burden Rw Winding burden Figure A 2 CT Burden Delta Connected CTs 3 Phase Fault A 2 BE1 87T Setting Notes 9171300990 Rev R SETTING NOTE 3 87T A 100 1 IDD 2129 4 2100 2 129 gt 9 109 02779 01 04 16 99 Assuming Zi Z I 155 Phase 2 carries twice the fault current returning from the relay to the CTs Therefore the maximum current is Imax 2x 109 B s 1 3 x Figure A 3 Phase Phase Fault Delta Connec
117. the worst case CT burden voltage for a three phase fault Va For wye connected CTs Vss Ir3 R Rp For delta connected CTs for three phase fault Iz Rw 3R 3Ry Note that the wye connection produces a lower burden on the CTs see Appendix A Note 2 Where le determined in Step 12 one way lead resistance in ohms Rw winding burden relay resistance in ohms lt 0 05 ohm Neglecting Hg use Rw and R from Figure 4 35 HIGH LOW Vp3 32 0 7 VB3 66 0 7 22 4V 46 2 V Step 14 Determine the worst case burden voltage for a line to ground fault Vac For wye connected CTs Vag Iro 2R Rp Where la determined in Step 12 one way lead resistance in ohms relay resistance in ohms For delta connected CTs Vao is a function of the proportion of positive sequence to zero sequence currents but may be approximated by the same equation for worst case 9171300990 Rev R BE1 87T Installation 4 45 Neglecting Rp use Rw and R from Figure 4 35 HIGH LOW VBG 19 5 0 7 70 2 0 7 13 6V 98 0 V NOTE Since a phase to ground fault looks like a phase to phase fault on the delta side of a delta wye transformer each CT only has to carry one times the one way lead burden Step 15 Determine the effective CT accuracy class Vce Base Accuracy Number of CT Turns in Use V eR Maximum Ratio NA ver HIGH LOW 400
118. ts of Step 18 set the UNRESTRAINED PICKUP LEVEL control Referring to the table on the BE1 87T front panel select the tap position X TAP that is higher than the result obtained in Step 18 Therefore for this example select SET position G 12 X TAP which is higher than the above result of 11 17 X TAP If this value exceeds 21 max setting raise the tap settings toward the upper end of the tap range If after the highest tap has been reached the unrestrained trip settings still exceeds 21 security is affected The user should remember that the 70 saturation is conservative A close look at the system L R and CT performance is recommended Chances are that the risk will be tolerable Slope Setting The slope equation determines the slope setting required to maintain a margin of about 12 of at the breakpoint of the slope characteristic This margin varies slightly with the actual taps but remains secure over the tap range Step 20 Determine the multiples of self cooled current 7 Refer to Appendix A Setting Note 5 Ig MVA sexr cooten ET MVA Where Tp relay current from Step 4 T the input tap from Step 9 MVAazir and MVArorce are given in Figure 4 35 9171300990 Rev R BE1 87T Installation 4 47 HIGH LOW 2 7912 y _ 00212 T 2 0 20 T 0 84 0 84 Step 21 Select the restrained slope setting 4 48 The recommended restr
119. um Function Differential Current 50 Hz 60 Hz 50 or 60 Hz Restrained Trip 2 x Pickup 81 ms 70 ms 49 ms Restrained Trip 10 x Pickup 73 ms 67 ms 37 ms Unrestrained Trip 2 x Pickup 64 ms 52 ms 57 ms Unrestrained Trip 10 x Pickup 32 ms 28 ms 10 ms BE1 87T Test Procedures 9171300990 Rev R OPERATIONAL TEST PROCEDURES The functional tests given below provide a simplified method of checking the relay trip performance relative to the front panel settings and indirectly the calibration Individual steps of the procedure are designed as a series of tests that are performed in the sequence shown rather than stand alone For a more comprehensive test refer to Verification Tests 5 Amp CT or Verification Tests 1 Amp CT earlier in this section CAUTION Do not proceed unless familiar with the Relay Operating Precautions the procedures described in Relay Disassembly and the procedures listed in the RESTRAINED PICKUP TESTING EXAMPLES at the beginning of this section These tests may be performed by removing the BE1 87T to a test station or with the relay installed CAUTION If testing an installed relay be sure to isolate the current inputs and the relay outputs from the system Basler electric test plugs p n 10095 are recommended for this purpose to isolate the relay as well as simplify the test setup For further information see Test Plug in Section 4 INSTALLATION Restrained Pickup NOTE When making restrained
120. units 6 Three phase units use the sum of the second harmonic from each phase to restrain each phase 7 Phase Targets are supplied on three phase units ONLY 8 Restrained Trip Contact e One contact for single phase units e One contact or one contact per phase available on three phase units B SAME AS gA RESTRAINED UNRESTRAINED C SAME AS gA RESTRAINED UNRESTRAINED OPTIONAL RESTRAINED CONTACTS FOR EACH OF 3 PHASES 1 87 SEE NOTE A D741 001b 7 11 94 Figure 3 2 Functional Block Diagram Phase B and Phase C 3 2 BE1 87T Functional Description 9171300990 Rev R Restrained Trip Output Restrained trip output contacts are subject to three types of restraint i e inhibit signals e Percentage restraint e Second harmonic restraint e Fifth harmonic restraint These signals are developed within the relay in response to external conditions and block the restrained output contacts from closing Percentage Restraint Percentage restraint developed from the maximum through current and the slope setting determines the minimum operating current 7o Figure 3 1 in a comparator where Jpop must be greater than Ivax to produce a Restraint Trip output The 7o desired trip level is adjustable on the front panel RESTRAINED PICKUP LEVEL switches shown in Figures 2 1 through 2 3 Comparators in the Calculate Max Individual Current circuit determine which input of a particular phase is receiving the greatest curre
121. using terminals 11 amp 13 Input 1 for both single phase and three phase units Step 2 Three Phase Units Only Set the Calibrate toggle switch S2 letter D of Figure 2 4 to the CAL position on each of the three Analog 1 boards These three toggle switches are readily 5 16 BE1 87T Test Procedures 9171300990 Rev R accessible on the right side of the relay when withdrawn from the case It is not necessary to pull out the circuit boards NOTE With two current sources in parallel apply the fundamental frequency and then add the required harmonic Step 3 Step 4 Step 5 Step 6 Step 7 Apply 0 4 A at 50 or 60 Hz as appropriate for the style to Input 1 The REST TRIP LED should be illuminated Increase the second harmonic current until the REST TRIP LED extinguishes indicating that the inhibit point has been reached Note the magnitude of the second harmonic component at the inhibit point To calculate the second harmonic inhibit percentage divide the second harmonic current measured in Step 4 by the current applied in Step 3 Divide the harmonic current by the fundamental current Factory setting is 12 0 3 for single phase units and 18 0 3 for three phase units Three Phase Units Only Repeat Steps 1 through 5 for phase B terminals 12 amp 13 and phase C terminals 14 amp 13 Three Phase Units Only Upon completion of above testing return the three calibrate toggle switches S2 letter D of Figu
122. y case is hard wired to earth ground with no smaller than 12 AWG copper wire attached to the ground terminal on the rear of the relay case When the relay is configured in a system with other protective devices it is recommended to use a separate lead to the ground bus from each relay Except as noted above connections should be made with a minimum wire size of 14 AWG Figures 4 7 through 4 10 show case terminals designations for four typical relay configurations Figures 4 11 through 4 14 show the internal connections of the BE1 87T Control circuit connections are shown in Figures 4 15 through 4 18 CAUTION To prevent possible false tripping the upper connection plug should be in place prior to removing or installing the lower connection plug BE1 87T AUX N O AUX COM AUX INPUTS RESTRAINED OUTPUTS COMMON NRESTRAINED SUPPLY STATUS POWER CONTACTS BE1 87T CONFIGURATION IS DEPENDENT ON STYLE SELECTED Figure 4 7 Case Terminals Single Phase 9171300990 Rev R BE1 87T Installation 4 9 BE1 87T rower RESTRAINED COMMON OA UNRESTRAINED INPUT 1 28 gc POWER CO OUTPUTS CONTACTS DA AUX N O OB INPUT 24 gc AUX COM AN CO AUX N 1 87 D437 002 9 23 94 N CONFIGURATION IS DEPENDENT ON STYLE SELECTED Figure 4 8 Case Terminals Three Phase Two Input Sensing Input Type E Output Option E RESTRAINED N POWER

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