the manual - TDK-Lambda Americas Inc.
Contents
1. 10 pos and TB2 12 neg 8 9 10 11 12 13 14 15 16 17 0 1MA FIGURE 8 REMOTE PROGRAMMING BY EXTERNAL CURRENT CURRENT MODE 1 3 7 parallel operation figure 9 Page 14 of 29 83 467 001 Rev A NOTE It is not recommended to operate more than three TCR power supplies in parallel without thorough evaluation by the user with counseling from the Engineering Department of Electronic Measurements Inc This will help avoid any failures in the application because of instability of the power supplies The simplest parallel connection is that of attaching the positive and negative terminals to their respective load points The procedure is as follows 1 Turn on all units open circuit and adjust to appropriate output voltage 2 Turn supplies off and connect all positive output terminals to the positive side of the load and all negative output terminals to the negative side of the load NOTE Individual leads connecting unit to the load must be of equal lengths and oversized to provide as low an impedance as practical for the high peak currents 3 Set the current controls clockwise 4 Turn units on one at a time until the sum of the power supply current capabilities exceed the load current drawn 5 Using the voltage controls balance each unit voltage for equal output current Balance the current of each unit for equality 6 Set the current controls to limit just above running current so that if a unit s output voltage dri2. 17 FIGURE 5 REMOTE PROGRAMMING BY EXTERNAL VOLTAGE VOLTAGE MODE Current Channel A voltage of 0 to 100 mV programs the output from zero to full rated current NOTE A signal from a higher potential source may be attenuated to this 100mV level by a resistor divider For best performance the source impedance of this divider must not exceed 100 Ohms 1 Remove the jumpers between terminals TB2 9 10 and 11 2 Connect the programming voltage source between terminal TB2 10 pos and TB2 12 neg TB2 1 2 3 4 5 6 7 8 9 1011 12 13 14 15 16 17 DDOD ODD ODD ODD DD DD D2DOD All 0 100MV FIGURE 6 REMOTE PROGRAMMING BY EXTERNAL VOLTAGE CURRENT MODE Page 13 of 29 83 467 001 Rev A 1 3 6 Remote programming by external current figures 7 amp 8 The front panel voltage or current control is not disabled in this programming mode The front panel control must be left in the clockwise position to maintain the programming constant or signal to the output A current of 0 1mA programs the output from zero voltage to full rated voltage or current Voltage 1 Remove the jumpers between terminals TB2 3 and 4 2 Connect the programming current source between terminals TB2 4 pos and TB2 6 neg TB2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 FIGURE 7 REMOTE PROGRAMMING BY EXTERNAL CURRENT VOLTAGE MODE Current 1 Remove the jumper between terminals TB2 9 and 10 2 Connect the programming current source between TB2
3. 2 should be off 6 Advance CURRENT CONTROL 6 one half turn and slowly advance VOLTAGE CONTROL 3 The DC VOLTMETER 4 will deflect from zero to maximum rating of the supply as this control is advanced completely clockwise The VOLTAGE INDICATOR 5 will be lit 7 Return all controls completely counter clockwise 8 To check out constant current first turn off supply Connect a shorting bar across the plus and minus output terminal at the back of the unit 9 Turn the circuit breaker on off switch to on Advance the VOLTAGE CONTROL 3 one turn clockwise and slowly advance the CURRENT CONTROL 6 The DC AMMETER 7 will deflect smoothly from zero to the rated current of the supply as this control is advanced clockwise The CURRENT INDICATOR 8 will be lit 10 Return all controls completely counter clockwise and turn unit off Disconnect output shorting bar 1 1 oVP operation figure a If supply is equipped with an overvoltage crowbar the front panel will contain OVERVOLTAGE ADJUSTMENT 9 This potentiometer may be adjusted through an access hole in the front panel NOTE All overvoltage circuitry has been properly adjusted to their respective unit before leaving the factory For trip levels less than the maximum output voltage or to check the overvoltage circuitry simply set the potentiometer 9 fully clockwise Now adjust the power supply output voltage to the desired trip level 3 and slowly adjust the potentio
4. Figure A Front Panel Controls and Indicators Figure 1 Normal Operation Figure 2 Remote Sensing Figure 3 Remote Programming by External Resistance Voltage Mode Figure 4 Remote Programming by External Resistance Current Mode Figure 5 Remote Programming by External Voltage Voltage Mode Figure 6 Remote Programming by External Voltage Current Mode Figure 7 Remote Programming by External Current Voltage Mode Figure 8 Remote Programming by External Current Current Mode Figure 9 Master Slave Power Connection Figure 10 Parallel Operation Master Slave LIST OF TABLES Table 1 Rating Table 25 26 28 29 29 GENERAL INFORMATION 1 1 INTRODUCTION This manual contains operation and maintenance instructions covering the TCR 3 Phase Power Supply series manufactured by Electronic Measurements Inc of Neptune NJ All models provide AC turn on off and circuit protection by means of a UL rated input circuit breaker Output control is provided by a 10 turn voltage control and a 1 turn current control which are monitored by front panel meters These meters are an optional selection between either an analog or digital display Input AC is applied to 3 pairs of bi directional connected SCRs placed within the delta connected primary of the main power transformer The secondary of this transformer is rectified and double LC filtered to provide a low ripple DC output It also has a dual amplifier one for voltage channel and one for
5. compensates for the voltage drop in the power distribution system and provides specified regulation at the point of load 1 1 2 remote programming The power supply output voltage or current can be controlled from a remote location by means of an external voltage source or resistance 1 1 3 parallel operation The power supply output can be operated in parallel with another unit when greater output current capability is required The parallel operation permits one master supply to control the other supplies 1 1 4 series operation Two power supplies can be used in series when a higher output voltage is required in the constant voltage mode of operation or when greater voltage compliance is required in the constant current mode of operation 1 1 5 Remote turn The power supply may be remotely turned on or off by application of a combination of external voltages or interlock control The open interlock potential is the applied external voltage level If the interlock function is used without an external control level the open interlock potential is 24 Vdc SPECIFICATIONS 1 2 1 AC input Standard AC input is 208 220 230 volts A three phase three wire system which will operate within full specification form 190 to 253 volts or optional voltage as specified Input AC phase rotation sequence is not Critical to this supply The phase to phase voltage balance requirement is 2 to achieve ripple specification Current Draw Per
6. current channel In addition it also has adjustment controls that will furnish full rated output voltage at the maximum rated output current or can be continuously adjusted throughout most of the output range These supplies may also be controlled locally at the front panel or remotely by external voltage current or resistance on rear mounted programming terminals VOLTAGE PROGRAMMING Voltage Programming 0 to 5Vdc Programs from 0 to full voltage output Current Programming 0 to 1mA into 5000 ohms Programs 0 to full voltage output Resistance Programming 0 to 5000 ohms Programs 0 to full voltage output CURRENT PROGRAMMING Voltage Programming 0 to 100mV Programs 0 to full current output Current Programming 0 to 1mA into 100 ohms Programs 0 to full current output Resistance Programming 0 to 100 ohms Programs 0 to full current output Page 1 of 29 83 467 001 Rev A Output voltage and current are continuously monitored by two front panel meters Input power is connected to a four screw terminal at the rear of the unit The output terminals are heavy busbars mounted on the rear of the unit A 17 screw terminal block at the rear of the unit provides expansion of the operational capabilities of the instrument A brief description of these capabilities are given below l 1 1 remote sensing Separate output sensing terminals are provided to remotely sense the power supply output at a distant load This feature
7. effect of this ripple on the measurement 1 2 7 stability The output voltage or current will remain within 0596 of full output for 8 hours after warm up under fixed line load and temperature conditions 1 2 8 transient response A 3096 step increase in power demanded by the load will cause a transient in the regulation output which will typically recover to within 296 of final value within 75 milliseconds 1 2 9 temperature coefficient Page 3 of 29 83 467 001 Rev A Voltage The temperature coefficient of the output voltage set point is 0 02 per degree centigrade of the maximum output voltage Current The temperature coefficient of the output current set point is 0 03 per degree centigrade of the maximum rating of the supply 1 2 10 ambient temperature Operating 0 C to 40 C Non Operating 40 C to 85 C Critical circuitry is thermostat protected so that in the event of an over temperature condition the unit is turned off until a safe temperature returns 1 2 11 cooling All units are air cooled and thermostatically protected Air enters at the front right side and exits at the front left side and rear 1 2 12 ripple The output voltage ripple specified in the Rating Table is the worst case ripple under any resistive load condition with the power line within specification Typically the highest ripple occurs at 50 output voltage current and is lower at maximum output voltage and power is approached Output rippl
8. or current channel is fed to the base of transistor Q110 which operates as a linear amplifier whose output is fed to the phase control circuit Q101 106 The mode indicator lights are controlled by the outputs of the voltage and current channels For example if the voltage channel is in control output of the current channel is negative This will cause current to flow through CR135 lighting the voltage LED When the current channel is in control current will flow through CR134 lighting the current LED The voltage signal developed across R164 is a source of feedback fed through R187 and C145 and R182 and C142 to stabilize the current and voltage channels respectively Additional loop compensation is provided by R183 and C143 and R185 and C144 A control signal that momentarily switches negative at the base of Q110 allows the collector ramp voltage to increase the firing line voltage earlier in the cycle thus increasing the SCR firing angle A positive going signal at the cathodes of CR136 and CR139 causes the output of the power supply to reduce by retarding the conduction of the SCRs This shows that the amplitude of the phase angle is directly proportional to the polarity of the base signal of Q110 The collector voltage of Q110 is approximately 7 to 8 volts at full conduction angle and 5 to 6 volts for minimum conduction angle SCR FIRING CIRCUIT Page 21 of 29 83 467 001 Rev A IV 5 IV 6 The SCR firing pulses are developed by p
9. 16 17 A WITH DRY CONTACT 16 17 B REMOTE ON OFF AC DC E FIGURE 1 NORMAL OPERATION Connecting Load Each load must be connected to the power supply output terminals using separate pairs of connecting wires This will minimize mutual coupling effects between loads and will retain full advantage of the low output impedance of the power supply Each pair of connecting wires must be as short as possible and twisted or shielded if strong AC or RF fields are present to reduce noise pickup If a shielded pair is used connect one end of the shield to ground at the power supply and leave the other end disconnected 1 3 2 remote sensing figure 2 In applications where the effect of the voltage drop IR of the DC load wires would adversely affect the performance of the load it is possible to sense the voltage at the load instead of the output terminals of the power supply Remote sensing will therefore remove the effect of changes in load current through the power distribution system The maximum available load voltage then equals the rated power supply output voltage less the total of the IR drop Connections for Remote Sensing 1 Remove jumpers between the following terminals TB2 1 and 2 TB2 7 and 8 2 Connect the positive point of load to TB2 2 3 Connect the negative side of the load to TB2 7 and 6 Page 10 of 29 83 467 001 Rev A 4 If the sense points are separated from each other by some distance it is sometim
10. 7 001 Rev A V MAINTENANCE V 1 V 2 V 3 GENERAL A regular scheduled preventive maintenance program is recommended for the TCR 3 Phase power supply As a minimum maintenance should consist of a thorough cleaning of interior and a visual inspection of components on printed circuit boards Even a relatively clean location reguires at least one inspection every six months INSPECTION AND CLEANING CAUTION Always unplug power supply from AC line before removing cover 1 Remove six 8 32 machine screws from both sides of top cover Loosen two 8 32 machine screws at top of back of unit 2 Cover can now be removed 3 Check for loose wires burn marks etc 4 A100 control board will snap out so it can be checked 5 Remove dust from in and around parts with a small long bristled brush or compressed air V 2 1 eguipment reguired for calibration and maintenance 1 Oscilloscope Dual Trace 20kHz bandwidth isolated from ground Tektronix 2213 with 10x voltage probe 2 RMS Multimeter 100 VDC 1000 VAC Hewlett Packard HP 3465A 3 VOM Simpson 260 4 Load egual to the output capability of unit CALIBRATION This procedure applies to the adjustment and calibration of a properly functioning unit only Any malfunctions must be corrected before proceeding with calibration It is only necessary to remove top cover to make these calibrations See Section 5 2 NOTE If an external shunt is being used connect it in serie
11. AT FULL LOAD VOLTAGE CURRENT RMS HEIGHT 4 900 35mV 17 5 4T900 6 900 35mV 17 5 6T900 30 500 20mV 17 5 30T500 The 15kW schematic is the same as the 10kW package except for 6 fans TWO connected between each of the 3 phases The fans are the same as the ones used on the 10kW unit The OVP part number is listed on the schematic 01 467 001 The OVP for this unit should be bought as a complete assembly therefore no schematic will be provided Page 29 of 29 83 467 001 Rev A
12. Control Board could be shorted Check transistor Q108 on the A100 Control Board could be open TURN VOLTAGE AND CURRENT CHANNELS UP SLOWLY CIRCUIT BREAKER SNAPS OFF One of the high power diodes located on the heatsink could be shorted Refer to Section 5 5 for diode replacement EXCESSIVE RIPPLE Check output filtering capacitors C16 and C17 Page 27 of 29 83 467 001 Rev A could be defective One of the main SCRs Q1 Q6 could be open Inductor coils L1 or L2 could be shorted SCR control circuit on the A100 Control Board could be defective 1 Check for equal ramp amplitudes across CR101 106 2 Check that the waveform across C109 114 drops rapidly to 1 4 volts UNIT IS OSCILLATING Check C142 and C145 could be defective CURRENT OR VOLTAGE CHANNEL DOES NOT REGULATE Check 104 and 0110 could be defective V 4 3 overvoltage troubleshooting Most overvoltage faults fall into two general categories 1 The circuit overvoltage fires at all times even when the trip point is adjusted to maximum Check SCRs Q201 and Q202 They could be shorted 201 could be defective 2 The overvoltage is completely inoperative at any trip point setting Check SCRs Q201 and Q202 They could be open 201 could be defective V 5 PRIMARY DIODE REPLACEMENT 1 The bottom and side cover is all one piece and must be removed to replace diodes Remove
13. IC201 Pin 2 samples the power supply output voltage level through voltage divider R202 R203 and R204 Capacitor C204 connected to Pins 3 and 4 determines the minimum duration of the overvoltage condition before the OVP trips When the input voltage rises above the trip point set by an internal reference source capacitor C204 begins charging When the voltage at Pins and 4 goes above the minimum duration output of IC201 Pin 8 goes positive and turns on Q201 Q202 and Q203 SCR Q201 is connected to the collector of Q110 When Q201 conducts it shorts the firing line inhibiting the input SCRs On low voltage power supplies the voltage available is not high enough to trip the circuit breaker therefore the charged energy from a 15V capacitor C206 is used to trip the breaker On power supplies above 10 volts C206 and CR206 are not used Q202 applies the DC output voltage to the circuit breaker Q203 and R211 serve as a low impedance high current short to crowbar the output to zero This will prevent voltage damaging overshoot which could occur with a shorted SCR DIGITAL METER A100 PCB The major component of the Digital Meter Printed Circuit Board A100 is a 3 1 2 digital analog to digital converter 1C17136 All necessary active devices are contained within including seven segment decoders display drivers reference and clock It also interfaces with a liquid crystal display and provides the backplane drive voltage Page 23 of 29 83 46
14. INSTRUCTION MANUAL FOR TCR 3 PHASE POWER SUPPLY 83 467 001 Revision B MODEL SERIAL NUMBER LAMBDA EMI 405 ESSEX ROAD NEPTUNE NJ 07753 TEL 732 922 9300 FAX 732 922 9334 TCR 3 Phase OPERATING SYSTEM MANUAL TABLE OF CONTENTS GENERAL INFORMATION 1 1 INTRODUCTION 1 2 SPECIFICATION INSTALLATION 2 1 INITIAL INSPECTION 2 2 POWER REQUIREMENTS 2 3 LOCATION OPERATION INSTRUCTION 3 1 TURN ON CHECK OUT PROCEDURE 3 1 1 Over Voltage Output 3 2 GENERAL OPERATION 3 8 MODES OF OPERATION 3 3 1 Normal Operation 3 3 2 Remote Sensing 3 3 3 Remote Programming 3 3 4 Remote Programming by External Resistance 3 3 5 Remote Programming by External Voltage 3 3 6 Remote Programming by External Current 3 3 7 Parallel Programming 3 3 8 Parallel Operation Master Slave 3 3 9 Series Operation 3 3 10 Remote Meters 3 3 11 Remote Turn On THEORY OF OPERATION 4 1 GENERAL 42 FLOW 4 3 SIGNAL FLOW 4 4 SCR FIRING CIRCUIT 4 5 REMOTE TURN ON 4 6 OVERVOLTAGE PROTECTION OPTION 4 7 DIGITAL METER A100 PCB MAINTENANCE 5 1 GENERAL 5 2 INSPECTION AND CLEANING 5 3 CALIBRATION 5 3 1 Ammeter Calibration 5 3 2 Firing Balance Page 19 19 20 22 23 23 24 24 24 25 25 5 4 TROUBLESHOOTING 5 4 1 Overall Troubleshooting Procedure 5 4 2 Troubleshooting Chart 5 4 3 Overvoltage Troubleshooting 5 5 PRIMARY DIODE REPLACEMENT 5 6 FAN REPLACEMENT 3 Phase 15kW addendum LIST OF ILLUSTRATIONS
15. Phase 2 5kW Units 12 Amps at full load 5kW Units 23 Amps 10kW Units 46 Amps AC line current is proportional DC load current Page 2 of 29 83 467 001 Rev A 1 2 2 option aC All models are available with optional AC inputs of INPUTS 200V 10 380V 10 415V 10 460 480V 414 505V 400V 10 1 2 3 line frequency 47 63hz 1 2 4 aC inrush All models are soft started so that during initial activation or reapplication on interrupted power the input SCRs slowly phase in from non conduction mode Since the SCRs are in series with the transformer primary there is no magnetic inrush current due to core memory 1 2 5 phase loss Loss of a phase voltage will inhibit power supply output and illuminate the front panel phase loss light The power supply is not damaged when the phase voltage is restored and normal operation will automatically resume 1 2 6 regulation Voltage Mode For line voltage variations or load current variations within the rating of the supply the output voltage will not vary more than 0 1 of the maximum voltage rating depending upon the unit Current Mode For line voltage variations or load voltage variations within the rating of the supply the output current will not vary more than 0 1 of the maximum current rating depending upon the unit On those units in which the percentage of voltage or current ripple exceeds the specified regulation the regulation will appear to be degraded because of the
16. TION This power supply is designed so that its mode of operation is selected by making strapping connections between terminals on terminal strip TB2 which is bolted to the rear panel of the power supply The terminal designations are silk screened on the rear panel of the power supply Refer to the following chart TB2 PIN PIN DESCRIPTION 1 Voltage V 2 Voltage Remote V REM 3 Voltage Programming Current V PROG 1 4 Voltage Amplifier V AMP IN 5 Voltage Programming Resistive V PROG R 6 Voltage Programming Resistive Common V PROG R COM 7 Voltage Remote V REM 8 Voltage V 9 Current Programming Current I PROG 1 10 Current Amplifier I AMP IN 11 Current Programming Resistive I PROG R 12 Shunt l 13 Inverted Amplifier INV AMP IN 14 Shunt 1 15 Pins 15 and 16 Remote Voltage Turn On 16 Remote V IN 16 Pins 16 and 17 Remote Dry Contact Turn On 17 Remote SW 1 3 1 normal operation Figure 1 Page 9 of 29 83 467 001 Rev A When shipped from the factory each supply is configured for constant voltage constant current local programming local sensing and single unit mode of operation This normal mode of operation is usually used in most applications All performance specifications unless otherwise stated are defined in this configuration Ripple programming speed transient response and stability are optimized with the supply so configured 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 15
17. ber networks R7 and C7 to integrate out narrow noise spikes The SCRs operating in conjunction with the firing circuits controls the amount of AC power applied to the primary of power transformer T1 This transformer converts the input AC voltage to the appropriate AC level for the load voltage and current The voltage is converted to DC by center tapped rectifiers CR1 through CR6 Some units have bridge type rectifiers At a high continuous load current L1 and L2 averages the DC voltage waveform at the input of the filter At low load current the inductance is ineffective and capacitors C16 and C17 changes to peak pulse amplitude for necessary filtering The phase delay of the input waveform ranges from approximately 60 degrees at the full rated output to nearly 180 degrees at low output voltage and current Resistor R10 acts as a pre load to assure stability when the load is disconnected from the power supply R11 is connected to the unregulated 15V supply which Page 19 of 29 83 467 001 Rev A IV 3 insures that 50 100mA always flows through R10 Without R11 and when the output voltage is low little or no current would be flowing through R10 so the output capacitors would never discharge to zero CR13 bypasses the current through R10 when the current through R10 exceeds the current through R11 The bias transformers T2 through T4 have two secondary windings Terminals 4 and 6 on each transformer produces 50V RMS with respect to the c
18. covering 4 Turn set over to rest on top Remove five 8 32 screws on each side of unit cover Diodes are located on bottom of unit mounted to a heatsink After removing diodes wipe heatsink clean of all compound 7 Puta fine coating of compound low thermal contact resistance on surface of diode that meets heatsink Be careful not to get any on threads of diode 8 Mount diodes to heatsink with sheetmetal PAL nut Torgue chart follows Page 28 of 29 83 467 001 Rev A DIODE THREAD SIZE TORQUE PRESSURE 1 4 28 threaded device 30 inch pound max torque 3 8 24 threaded device 120 inch pound max torque 1 2 20 threaded device 130 inch pound max torque 3 4 16 threaded device 30 foot pound max torque 9 Use anew nut when a new diode is installed V 6 REPLACEMENT After the fan is replaced the voltage across the fan motor should be measured and compared to the nameplate rating If the voltage is not correct change the series resistor R18 R19 R20 R21 R22 R23 TCR THREE PHASE 15kW ADDENDUM This addendum covers the difference between the 2 5 10kW package and the 15kW AC INPUT The AC line current will be approximately 60 amps and the front panel circuit breaker is 70 amps COOLING The air flow is from right to left with some air flow out the top and back RATING TABLE OUTPUT RATINGS OUTPUT RIPPLE PANEL SIZE MODEL TCR VOLTAGE
19. d be grounded to terminal TB2 14 and other end left floating 1 3 11 remote turn on External Voltage Source Remove link from TB2 16 and TB2 17 Connect a DC source of 12 24V to terminal TB2 15 positive and TB2 16 negative When AC is used 24 115 volts on terminals TB2 15 and TB2 16 the unit is no longer polarity sensitive Dry Contact Connect a switch or contactor between terminals TB2 16 and TB2 17 Contact closed unit will be on Page 17 of 29 83 467 001 Rev A TCR 34 POWER SIGNAL FLOW DIAGRAM MEE SCR LCLC MODULE TI FILTER NAL CURRENT MODE VOLTAGE R16 15V COM 15 CRISE CR136 OUTPUT 5K 10T VOLTAGE 5 AC CHANNEL DROP j OUT bad k eo Gu Sane s SOFT VOLTAGE R17 ZN START CHANNEL 100 REF CURRENT 1 CHANNEL 10 CR135 REMOTE CURRENT 9 TURN ON CHANNEL NI Z REF a 15 VOLTAGE MODE N 16 7 Figure 11 Page 18 of 29 83 467 001 Rev A IV THEORY OF OPERATION IV 1 IV 2 GENERAL The TCR 3 Phase power supply has an SCR module connected in each phase These modules work in conjunction with the firing circuit and a feedback loop which is the constant voltage constant current ored circuit The feedback loop determines the firing angle of the SCRs ensuring a regulated AC input voltage is applied to the primary of the power transformer This regulated AC voltage is then adjusted to
20. d in series simply by connecting the negative output terminal of one unit to the positive output terminal of the other The adjustment of each unit functions independently and the total output voltage is the Page 16 of 29 83 467 001 Rev A sum of each unit output voltage NOTE The voltage at any output terminal must never exceed 600V with respect to chassis ground SEE Application note for series master slave operation Consult Electronic Measurements Inc Engineering Departments for series operation of more than two supplies 1 3 10 remote meters A remote voltmeter may be connected between terminals TB2 2 pos and TB2 7 neg If remote sensing is also being used the remote voltmeter will indicate the voltage at the load To indicate the voltage at the power supply output terminals connect the remote voltmeter between terminals TB2 1 pos and TB2 8 neg A remote millivoltmeter calibrated in amperes may be connected between terminals TB2 12 neg and TB2 14 pos A voltage of 0 to 100mV across these terminals indicates output current from zero to full rating unless otherwise specified see main schematic To compensate for voltage drops in long remote ammeter leads a meter movement having a full scale sensitivity of the less than 100mV is used in series with a Calibrating resistor The leads to the remote meters should be twisted and if strong AC or RF fields are present the leads should be shielded One end of the shield shoul
21. e jumper between terminals TB2 4 and 5 2 Connect the programming resistance between terminals TB2 3 amp 4 and TB2 7 Current Channel A resistance of 0 to 100 Ohms programs the output from zero to full rated current Prog Ohms 100 X Desired Current Full Rated Current 1 Remove the jumper between terminals TB2 10 and 11 2 Connect the programming resistance between terminals TB2 10 and 12 TB2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 100 5 FIGURE 4 REMOTE PROGRAMMING BY EXTERNAL RESISTANCE CURRENT MODE CAUTION An opening in the remote programming circuit is effectively a high programming resistance and will cause an uncontrolled voltage or current rise to the maximum output of the power supply This may cause possible damage to the power supply and or the load For this reason any programming resistor switch must have shorting contacts This type of shorting switch connects each successive position before disconnecting the preceding one 3 5 remote programming by external voltage figures 5 amp 6 Page 12 of 29 83 467 001 Rev A The front panel voltage or current control is disabled in this operating mode Voltage Channel A voltage of 0 to 5V programs the output from zero to full rated voltage 1 Remove the jumpers between terminals TB2 3 4 and 5 2 Connect the programming voltage source between TB2 4 pos and TB2 6 neg 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
22. e voltage and current is 31 higher than shown when supply is operated at 50Hz line frequency Page 4 of 29 83 467 001 Rev A RATING TABLE OUTPUT RATINGS OUTPUT RIPPLE PANEL MODEL TCR 50 C Voltage Full Load Voltage V Current A RMS Height 0 7 5 0 300 35mV 7 7 5T300 0 6 0 600 30mV 8 75 6T600 0 6 0 900 30mV 12 25 6T900 0 10 0 250 35mV 7 10T250 0 10 0 500 35mV 8 75 10T500 0 10 0 750 35mV 12 25 10T750 0 20 0 125 20mV 7 20T125 0 20 0 250 20mV 8 75 20T250 0 20 0 500 20mV 12 75 20T500 0 30 0 100 15mV 7 30T100 0 30 0 200 15mV 8 75 30T200 0 40 0 60 15mV 7 40T60 0 40 0 125 15mV 8 75 40T125 0 40 0 250 15mV 12 25 40T250 0 50 0 200 18mV 12 25 50T200 0 80 0 30 25mV 7 80T30 0 80 0 60 25mV 8 75 80T60 0 100 0 100 40mV 12 25 100T100 0 120 0 20 40mV ze 120T20 0 120 0 40 40mV 8 75 120T40 0 160 0 15 60mV 7 160T15 0 160 0 30 60mV 8 75 160T30 0 160 0 60 60mV 12 75 160T60 0 250 0 10 90mV 7 250 10 0 250 0 20 90mV 8 75 250T20 0 250 0 40 90mV 12 85 250T40 0 500 0 5 125mV 7 500T5 0 500 0 10 125mV 8 75 500T10 0 500 0 20 125mV 12 25 500T20 TABLE 1 The TCR units have a panel width of 19 inches and a depth of 22 inches INSTALLATION Page 5 of 29 83 467 001 Rev A 11 1 1 2 1 3 INITIAL INSPECTION Before shipment this instrument was inspected and found to be free of mechanical and electrical defects As soon as the unit is unpacked inspect fo
23. enter tap terminal 5 This provides two sine wave signals spaced 180 degrees out of phase for referencing the SCR firing circuit to the line frequency A voltage of 20V RMS is produced between terminals 7 and 8 of each transformer Their voltages are full wave rectified on the A100 Control Board to provide and 15 VDC for control circuitry SIGNAL FLOW All the controlling circuitry for regulation of this supply is located on the A100 Control Board schematic 01 119 000 Explanation of signal flow is as follows The 18 20 volts AC from bias transformers T2 through T4 provides a three phase input to the bias section of the A100 Control Board These inputs are used for different facets of the controlling process of the power supply Most of the circuitry uses the and 15 VDC regulated by IC101 and IC102 IC101 produces a 15 VDC with a 150 mA load and IC102 a 15VDC with a 30mA load The unregulated DC voltage is used for voltage with the remote turn on when dry contact control is used When one of the input phases drops out the conduction cycle of Q108 is reduced allowing capacitor C129 to start charging After three cycles of line frequency C129 charges sufficiently to cause Q109 to conduct which turns on the front panel phase loss LED This effectively grounds the drive circuit preventing the generation of further SCR gate pulses which shuts down the output of the unit The AC dropout circuit prevents the power supply from operating w
24. es necessary to connect a capacitor across the load or between TB2 2 and TB2 7 within the range of 5 to 501 NOTE Since the voltmeter is internally connected to the sensing terminals it will automatically indicate the voltage at the load not the power supply output terminal voltage 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 FIGURE 2 REMOTE SENSING 3 3 remote programming This power supply may be operated in a remotely programmed mode externally controlled by the use of an external resistance The wires connecting the programming terminals of the supply to the remote programming device should be twisted or if strong AC or RF fields are present shielded CAUTION If the remote programming function fails or is inadvertently adjusted so that the output voltage is programmed to levels of greater than 1596 above ratings damage to the output filter capacitors may occur To protect against this it is suggested that the overvoltage protection option be used to limit the maximum voltage excursion and safely shut the power supply down Page 11 of 29 83 467 001 Rev A 3 4 remote programming by external resistance figure amp 4 Voltage Channel TB2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 FIGURE 3 REMOTE PROGRAMMING BY EXTERNAL RESISTANCE VOLTAGE MODE A resistance of 0 to 5000 Ohms programs the output from zero to full rated voltage Prog Ohms 5000 X Desired Voltage Full Rated Output Voltage 1 Remove th
25. fts upward it will become current limited rather than carry an excessive share of load current IMPORTANT When the units contain the overvoltage option do not connect them in parallel without consulting the Engineering Staff of Electronic Measurements Irreparable damage will occur if one of the paralleled units goes into overvoltage without proper paralleling of the OVP option RAB RCB RDE RFE Page 15 of 29 83 467 001 Rev A FIGURE 9 MASTER SLAVE POWER CONNECTION 1 3 8 PARALLEL OPERATION MASTER SLAVE In this configuration the power supply designated the master is used to control the voltage and current operation of all other supplies referred to as slaves 1 Disconnect the following jumpers of all slaves TB2 13 and 14 TB2 9 10 and 11 2 Connect a jumper between TB2 10 and 12 of all slaves 3 Connect a wire between the master supply TB2 12 and TB2 13 of each slave 4 See Figure 9 for and power connections 5 Set the voltage control of each slave fully clockwise 6 Turn each slave on and then the master 7 Adjust the master for required output voltage or current The output leads from each power supply must be of equal resistance to a point of load near the supply to assure equal sharing MASTER TB2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 9900090 2 9 10 11 12 13 14 15 16 17 FIGURE 10 PARALLEL OPERATION MASTER SLAVE 11 3 9 series operation Two TCR power supplies can be operate
26. hen the AC drops below operating range This circuit works as follows C128 will start discharging through R149 This will cause Q107 to start conducting grounding the firing line to the SCRs and resets the soft start circuit Once input power is at the operating level the soft start circuit will reset in the following manner Capacitor C134 slowly starts charging through the base of Q110 As C134 charges the base current will decrease allowing the collector voltage of Q110 to slowly rise which gradually increases the conduction angle of the SCRs Separate constant current references are provided for the voltage and current channels The collector current of Q111 drives the voltage channel and Q112 the current channel These current sources are referenced by the voltage across CR133 a temperature compensated zener diode Since the voltage difference across the summing junction of IC104 Pin 2 is essentially zero the voltage across CR133 also appears across the series combination of R167 and R168 also R171 and R173 since the Vbe of Q111 and Q112 is essentially equal A constant voltage across a fixed resistance produces a constant current A constant emitter current Page 20 of 29 83 467 001 Rev A IV 4 produces an essentially constant collector current The current from each of these sources is adjustable to 1mA by R167 and R171 The reference current level for the voltage channel flows from J107 2 to TB2 3 With jumpers between termi
27. inals must be heavy enough leads to prevent substantial IR drops between the output terminals and the load Remote sensing can be used to compensate for IR drops Reference Section 3 3 2 LOCATION This instrument is fan cooled Sufficient soace must be allotted so that a free flow of cooling air can reach the sides of the instrument when it is in operation It must be used in an area where the ambient temperature does not exceed 40 C Page 6 of 29 83 467 001 Rev A lil OPERATING INSTRUCTIONS IIl 1 VOLTAGE CURRENT O V ADJUST PHASE LOSS TCR POWER SUPPLY FIGURE A FRONT PANEL CONTROLS AND INDICATORS TURN ON CHECK OUT PROCEDURE 1 The front panel surface contains all the controls and indicators necessary to operate the supply in its normal mode The following checkout procedure describes the use of the front panel controls and indicators Figure A and ensures that the supply is operational This preliminary check of the supply is done without a load connected 2 Check the barrier jumper straps on the back of the unit as shown in Figure 1 showing TB2 strip normal operation 3 Set all controls completely counterclockwise 4 Turn the CIRCUIT BREAKER 1 on off switch to on The fans will start immediately but there is a 10 to 15 seconds delay before voltage or current output will occur This is caused by the soft start circuit Rev A Page 7 of 29 83 467 001 Rev A 5 The PHASE LOSS INDICATOR
28. meter 9 counterclockwise until OVP trips turning off the set Once fired the SCR remains on until its anode voltage is removed decreased below its on level or until anode current falls below a minimum holding current A power supply that has been thrown into crowbar must have its input power momentarily removed to extinguish the on SCRs Turning the unit off and then on again will reset the OVP provided the output is not adjusted above the trip point The overvoltage range is from 50 to 100 of the maximum output voltage of the unit If any of the above events do not occur the supply is defective and must not be operated Depending on circumstances either warranty service or troubleshooting as described elsewhere in this manual is required Page 8 of 29 83 467 001 Rev A IIl 2 111 3 GENERAL OPERATION The voltage and current controls local and remote set the boundary limits for the output voltage and current respectively The relationship of load resistance to control settings determines whether the power supply is operating in constant voltage or constant current mode Automatic crossover between modes occurs at the following load resistance value Voltage Control Setting Volts LoadHesistan ce Ohms ee eT Current Control Setting Amps At higher load resistance the power supply operates in the constant voltage mode and at lower resistance in the constant current mode MODES OF OPERA
29. nals TB2 3 4 and 5 the voltage level produced when this current flows through the voltage control R16 is applied through J107 Pin 10 of 104 The signal on the other input of IC104 Pin 9 is derived from the power supply output voltage level through voltage divider R177 plus R178 and R179 Maximum rated output voltage produces 5 VDC at Pin 9 of IC104 With R16 in the fully clockwise position 5 VDC is applied to Pin 8 of IC104 If the attenuated output voltage changes from the value set by R16 because of load changes for example an error signal will be developed at the output of IC104 Pin 10 This error signal via the SCR control circuitry will cause a proportional change in the output voltage so as to bring the voltage on Pin 9 of IC104 equal to that applied to Pin 8 The action of the current channel is identical to that of the voltage channel with the exception that the controlled quantity is being sampled across the shunt R12 This sampled voltage is compared to the reference voltage produced at Pin 6 of IC104 which is established from the front panel current control R17 0 to 100 mV for all units except 600 and 900 amps which are 0 to 50 mV The output of the voltage channel amplifier and the current channel amplifier are ored together by diodes CR136 and CR139 Whichever channel has a higher positive output signal over rides the effect of the other and becomes the channel controlling the DC output The output of either the voltage
30. r any damage that may have occurred in transit Check for broken knobs or connectors that the external surface is not scratched or dented meter faces are not damaged and that all controls move freely Any external damage may be an indication of internal problems NOTE If any damage is found follow the Claim for Damage in Shipment instruction in the warranty section of this manual POWER REQUIREMENTS This power supply requires a three phase input of the specified voltage and frequency with nominal voltage line to line three wire system Phase rotation need not be observed when connecting power line to the input terminals of the power supply No neutral connection is required but for safety the chassis ground terminal marked GRD must be connected to earth ground in accordance with electrical code requirements All AC input connections are made at the rear terminal block TB2 with the insulated rectangular covering Install the three phase line to terminals marked A B and C Connect the ground line to terminal marked GRD Reinstall cover plate The user should ensure that the AC input wires are of the proper gauge For example the line current is 50 ampere maximum for a 230 VAC input dictating that each conductor be at least number 8 gauge wire The safety ground wire must be the same gauge as the AC input wires to ensure that it does not open and create a safety hazard Load wires to be connected to the POS and NEG output term
31. roperly timed conduction of Q1 thru Q6 This is accomplished by the combination of the phase related AC signals from terminals 4 5 and 6 of T2 T3 and T4 and the variable level from Q110 Examining the typical firing circuit for one SCR only R101 and CR101 produce a 12V square wave at line frequency with axis crossings at 0 180 R107 and C102 integrate the square wave into rising and falling ramp voltages with transition in voltage direction occurring just past 0 and 180 due to the phase shifting effect of the RC network When a positive DC level from Q110 via J7 15 is superimposed on the ramp voltage across C102 Q101 will be driven into conduction at some time during the positive going position of the ramp This conduction causes a sudden current flow in the primary of T101 and a resultant pulse of trigger current from the secondary winding of T101 to the gate of SCR Q1 Operation of the opposite firing circuit is identical except for 180 displacement of the gate pulse which fires Q2 when its anode is positive C109 through C114 store the SCR gate pulse energy and C108 and R128 serve as a filter to prevent pulse loading of the 15V supply Resistors designated 3 on the A100 schematic are selected at test to equalize SCR firing angles Thermal switch TS1 is connected across C134 If the diode heatsink temperature rises excessively the thermal switch closes causing Q110 to be driven into saturation thus shutting down the power s
32. s with the short 1 Connect a voltmeter across the plus and minus sense leads of the shunt capable of the shunt voltage The internal shunt of the unit is either 50 or 100 mV 2 Turn CURRENT and VOLTAGE control completely clockwise 3 Turn power supply ON 4 Adjust the ICAL control R171 until the current rating of the unit is achieved Page 24 of 29 83 467 001 Rev A V 4 V 3 1 ammeter calibration 1 Connect the reference ammeter with shunt as applicable in series with a load or short circuit across the output terminals 2 Turn the VOLTAGE control fully clockwise 3 Check the zero adjustment of the front panel ammeter 4 Turn the power supply on 5 Adjust the CURRENT control so that the reference ammeter indicates full rated output current of the power supply 6 Adjust R14 located just behind the front panel until the front panel ammeter reading equals that of the reference ammeter Analog meters V 3 2 firing balance 1 Connecta load to the unit 2 Connect oscilloscope probe x10 on TB2 1 and ground on TB2 8 3 Adjust R120 R123 R126 for even peak voltages from cycle to cycle of the DC output TROUBLESHOOTING The power supply is divided into two basic circuit areas power flow and signal control The power flow circuitry consists of circuit breaker SCRs power transformer rectifiers choke and capacitors as well as the cabling interconnecting them The signal control circuitry is contained on the remo
33. the proper level by the power transformer After being full wave rectified and filtered a constant output voltage or current is produced POWER FLOW This section discusses the basic theory of power and signal flow of the TCR three phase power supply If used as a supplement to the maintenance data provided in Section V it will aid in isolation of unit faults Refer to Figure 11 block diagram of power and signal flow plus schematics 01 467 001 01 119 000 and 01 120 000 when reading this section Explanation of power flow is as follows At turn on a three phase AC input passes through the RFI filter circuit breaker CB1 to the SCR module networks The SCR modules contain two SCRs per module which are connected in reverse parallel Each SCR conducts upon the simultaneous application of a negative voltage to its cathode input AC and a positive voltage to its gate lead During the positive half cycle Q2 Q4 and Q6 is conducting and during the negative half cycle Q1 Q3 and Q5 will conduct The gate signal must be from 1 3 volts for the SCR to fire The firing angle of the SCR determines the amount of AC power applied to the input transformer Thus the amplitude of the DC output of an SCR that is fired at an early point of the input cycle provides a higher output than one that is fired later in the input cycle Because of the ease with which SCRs are fired by narrow pulses the gate cathode terminals are paralleled by low impedance snub
34. unt common or a negative output terminal The chart that follows is a troubleshooting guide that should aid in discovering operational problems in the supply V 4 2 TROUBLESHOOTING CHART START PROBLEM Turn Supply On Output goes high Full scale or above If unit contains OVP option Circuit breaker trips 1 Turn set off 2 Disconnect A100 board from SCRs pulling plugs J1 J6 3 Turn set on Page 26 of 29 83 467 001 Rev A PROBLEM REMEDY SET STILL OUT OF CONTROL SHORTED SCR SET NO LONGER OUT OF CONTROL CHECK R16 AND R17 COULD BE OPEN Check R16 1 Connect digital meter to J7 2 and common 2 As R16 is rotated through its ranges the voltage across it will vary from zero to 3 5 volts Check R17 1 Connect digital meter to J7 9 and common 2 As R17 is rotated through its range the voltage across it will vary from 0 50 or 0 100mV depending on the unit Check transistor Q110 on the A100 control board could be open UNIT ON BUT NO OUTPUT PHASE LED LIT Check AC input voltage Check AC signal at J113 2 3 and 4 on A100 Control Board Check output of bias transformer T2 T3 and T4 across Pins 7 and 8 Open circuit voltage 20 volts AC If there is not voltage at the bias transformers check fuses F1 3 PHASE LED NOT LIT Check transistor Q110 on the A100 Control Board could be shorted Check transistors Q107 and Q109 on the A100
35. upply output The thermal switch will reset automatically when the heatsink temperature drops sufficiently REMOTE TURN ON Remote Turn On allows the user to turn the supply on from a remote location with 12 24 VDC or 24 115 VAC or a dry contact closure 1C103 isolates the remote turn on circuitry from the power supply common Transistor Q110 is held in saturation by the 15 volts of the bias supply through R157 and CR130 When the internal LED of 103 is activated by power at Pins 1 and 2 the internal darlington transistor causes most of the 15 volts to be shunted to ground This allows Q110 to start amplifying When a N O voltage switch dry contact for remote turn on is used Q113 L101 and CR129 supply the control signal for the optical isolator Q113 is connected across the unregulated 20 DC volts of the bias supply and is used as a relaxation oscillator Each time Q113 conducts it discharges C147 through L101 inducing a voltage in its secondary winding This voltage is rectified by CR129 and filtered by C156 When a switch is connected between J12 3 and J12 2 the voltage will make a complete loop to operate the optical isolator OVERVOLTAGE PROTECTION OPTION A200 PCB 01 120 000 Page 22 of 29 83 467 001 Rev A IV 7 The OVP option protects the power supply and the load from excessive output voltage caused by a failure in the control circuitry of the power supply or a defect or misadjustment in the remote control circuit
36. vable printed circuit card Most unit malfunctions will originate on the circuit card Reviewing the Theory of Operation is recommended before starting to troubleshoot the supply WARNING When servicing supply dangerous voltage levels exist Be especially careful of personnel and equipment when measuring primary circuitry since this is at line potential V 4 1 overall troubleshooting procedure 1 Check for obvious troubles such as input power failure loose or incorrect strapping on rear terminals of defective meter 2 Itis common for the trouble to be caused by the DC bias or reference voltages thus it is a good practice to check voltages on the A100 control board before proceeding to the next step The A100 board may be disconnected from the SCRs by pulling plugs J1 J6 Some voltages to check with respect to negative terminal on standard units are Page 25 of 29 83 467 001 Rev A IC101 Pin 15 volts 5V IC102 Pin 3 15 volts 5V IC103 Pin 5 2 3 volts 104 Pin 11 15 volts 5V Q110 Collector 3 8 volts This voltage is clamped at 10 volts by CR132 3 Disconnect load and proceed to the next step 4 Troubleshooting is more effective if the unit is operated in the normal mode Normal Programming Section 3 3 1 5 Before turning on the supply turn both CURRENT and VOLTAGE channel controls completely off counterclockwise Where only one terminal is specified measurements are made with respect to sh
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