Position Indicator Typ 4748 Mounting and operating instructions EB
Contents
1. 9419 961 62 6 61 UQA 9 uapa LANYA usyorupadiqe ee MALEGA Ee 5 pun MeN Laune Spy 8 1 15 1 Ia 1 GIP PIMOS s erie 49 dp ung Lais M i SUIS E202 I T6 X3 AN ONNDINIEHOSFISLYAINNYOFINON m YNejsuesapung Syas uy9aL y9syeyis yd SAMSON AG 5 UND REGELTECHNIK Weism llerstra e D 60314 Frankfurt am Main Postfach 10 19 01 D 60019 Frankfurt am Main Telefon 0 69 4 00 90 Telefax 0 69 4 00 95 07 8363 5 03 952. CH 1129 1 28 27 26 221 1 24 21 20 Fig 4 Attachment to valve with rod type yoke 2 2 Attachment to positioner To attach the position indicator with the short lever to a Type 765 2 or Type 763 Positioner proceed as follows Install the O ring 30 on the left hand and right hand side of the inter mediate piece 31 Insert two screws 33 through the position indicator and the inter mediate piece and place them against the positioner Insert the nuts 32 in the posi tioner housing and tighten the screws 33 Fasten pin 1 3 to the lever 1 of the posi tioner using the nuts 22 so that the short lever ofthe position indicator is coupled The instruments are designed in accordance with degree of protection IP 54 For this pur pose exchange the screw plug in the cover of the positioner for the one installed in the cover of the position indicator For IP 65 Re place vent of the position indicator by a filter order no 8504 0666 2 3 Housing cover After the position indicator has been fitted on the control valve make certain that the vent plug on the housing cover points downwards when the valve is installed in the plant Fig 5 Attachment with intermediate piece to e g a Type 765 Positioner 4 Wi SC PSSST 3 Electrical connection The terminal assignment is illustrated in Fig 6 or marked on the PCB To check and monitor the output signal of the p
3. gt gt or lt gt To change the operating direction slightly lever off the plug at the end before removing it Then remove the plug completely turn it 180 and finally reinstall it Attachment to control valve left and to positioner right View onto plate 2 Attachment to control valve left and to positioner right 0 actuator on top Operating direction symbol on plug Operating direction symbol on plug Valve position gt gt lt gt Valve position gt gt lt gt Closed 20 mA AmA Closed AmA 20 mA Open AmA 20 mA Open 20 mA AmA 4 2 Adjustment of zero point and span Fig 7 Zero point ZERO The zero point is pread justed using the switches 3 and 4 and fine ad justed at the potentiometer ZERO This adjust ment is always related to 4 mA Span SPAN The span and thus the upper range value is preadjusted using the switches 1 and 2 and fine adjusted at the poten tiometer SPAN This adjustment is always re lated to 20 mA Example Consider a control valve which is moved from the closed valve CLOSED to the open posi tion valve OPEN The feedback signal must pass through the range of 4 to 20 mA The position indicator is attached on the left hand side of the valve For adjustment of zero and span connect a suitable power source to the terminals 31 and 32 To check the output signal remove the jumper connecting the terminals 81 and 82 Then conn
4. Position Indicator Typ 4748 Fig 1 Type 4748 1 Design and principle of operation The Type 4748 Position Indicator is used to ensure a certain relationship between the valve position travel and the analog output signal of 4 to 20 mA If the output signal of the position indicator is transmitted to e g an indicating instrument the current valve travel can be checked and monitored Edition March 1993 The position indicator is mounted to pneu matic control valves designed as either cast iron yoke valves acc to Namur or valves with rod type yokes direct attachment to valve respectively Furthermore the position indi cator can be used in combination with the Type 763 or 765 2 Positioners positioner at tachment Mounting and operating instructions EB 8363 E The valve travel is converted into a rotary mo tion which is transmitted via pin 1 1 and lever 1 to the solenoid system 2 of the posi tion indicator As a result the magnetic field changes and in this way also the voltage in the Hall sensor 2 The electronic compo nents connected behind the sensor convert this voltage into a load independent current signal of 4 to 20 mA For adjustment of zero and span the position indicator is provided with 4 micro switches preadjustment and 2 potentiometers fine adjustment The output characteristic of the position indicator can be reversed by means of a plug which must be turned 180 Th
5. ect a suitable ammeter At first adjust the desired operating direction by properly installing the 7 pin plug In our example the symbol lt gt on the plug must face upwards see table 1 Should an other symbol be visible on the plug remove the plug turn it 180 and finally reinstall it Adjustment of zero point Use input signal to the positioner to move the control valve to the closed position valve CLOSED travel 0 Read off the ammeter the reading must be approx 4 mA Use the ZERO potentiometer to correct slight deviations until the ammeter shows exactly 4 mA If deviations are considerable use the swit ches 3 and 4 to set a mA value which is within the adjustment range of the ZERO potentiometer Subsequently adjust this ZERO potentiometer until the ammeter shows exactly 4 mA zero Adjustment of span Use input signal to the positioner to move the control valve to the fully open position valve OPEN travel 100 Read off the ammeter the reading must be approx 20 mA Correct slight deviations at the potentiometer SPAN until the ammeter shows exactly 20 mA If deviations are considerable use the swit ches 1 and 2 to set a mA value which is within the adjustment range of the SPAN potentiometer Subsequently adjust this SPAN potentiometer until the ammeter shows exactly 20 mA span Since the adjustments of zero point and span slightly influence one another the poten tiometers must be read
6. is means the valve position CLOSED can be optionally indicated by either 4 or 20 mA Lever for valve travel Pin Solenoid system Sensor with temperature sensitive resistor NN Measuring amplifier Switches and potentiometer for pre and fine adjustment of ZERO Row Fig 2 Functional diagram 2 2 1 5 Switches and potentiometer for pre and fine adjustment of SPAN 6 Output stage 7 Constant voltage source 8 Constant current source 8 7 Qe Travel 2 3 4 5 6 1 er BEE un x gt gt gt gt gt HH CG Span G 24V eee I E 1 1 Technical data 4748 0 4748 1 Output signal Two wire circuit 4 20 mA Permissible load Ry 0512 87770 mA Output circuit Intrinsically safe Supply Two wire system 24 V Voltage range 12 45 V Only in combination with an intrinsically safe circuit Performance Characteristic output proportional to input conformity error lt 1 1 Hysteresis lt 0 6 7 Response lt 0 1 Effect of supply lt 0 1 with voltage changes within the given limits HF effect lt 1 150 MHz 1 watt power output 0 5 m distance Effect of load lt 0 1 Permissible ambient temperature Max 60 C Tempera
7. justed until both values are correct ZERO SPAN Fine adjustment Fig 7 Adjusters Preadjustment PTB Certificate for Type 4748 1 T T 93819 Leet 20 91 Gromyasunesg CS 91 9 0511 1 9999 0511 1 6699 0511 7999 0511 5 9999 0911 2 T Beih 0661 11 60 tan Bunuyspez zZ 3229 Tp Sunqiasyasag I we vogal yas ajun vage Jazunsbungnag aeq6isselyseu ADA PULS IBPLTEdEM FAILALIYMPUT SASULE awesyalm alg NBO 4 wu 000 1 52 O TUBTAIMISYIOH JLU 1 2 017 asaysisuahia ajBtuyayasag ue gngyssuy unz anu ZE pun TE II el 9 Hoysay susd g Juezynyaspunz ul rr 1844WOI2S PUBL DEM ays D 09 rr 2 08 ITER 51 9 nz sap 154 55915 anzesadway pun uneJadusrsdungs un ashLsseinz ewixeu uayasimz Bunupsonz alg Layutavanays pun Laboy saura Bun Latz La yuelp Jap owy4aqasbunt 535 vag 02 9 T6 4 919 BunbiursyssagszgFimiojuoy ETA popsuosapung Eydsjuy9 yas oyis yg BEELI 65 SEA ESCH CRE d OCH 00 teg eebe EES Lata EIERE Ee APO Leg ap Fe Sal Goes au EE Ee 1561 40 91 Biamyosuneg vep am
8. nd washer in the opening of the lever If the pin 1 1 is to be mounted to the clamp ing plate 20 slide the bracket order no 0300 0969 onto the lever This bracket will then clamp the pin in the oblong hole of the lever Attention With this type of assembly how ever a linearity error of up to 1 6 must be taken into account For direct attachment of the position indicator to the valve install the short pin 1 3 in the hole of the positioner lever 2 1 Attachment to control valves The adapter kit order no 1400 5745 is re quired for attaching the position indicator to cast iron yoke valves For rod type yoke valves rod 18 to 32 mm an adapter kit order no 1400 5342 is required additionally In addition to the components contained in the first adapter kit the latter contains a mounting plate 28 For attachment of the position indicator to valves having nominal sizes of DN 150 or larger Series 240 and 250 proceed as il lustrated in drawing no 1070 6002 Q The instrument is designed in accordance with degree of protection IP 65 The O ring 8 x 1 5 mm contained in the adapter kit is to be placed under the washer 29 2 1 1 Attachment to cast iron yoke valves Fig 3 Secure plate 20 to the coupling clamp 24 of the valve using the associated screws 21 Unscrew cover of the position indicator At tach instrument to the valve with screw 11 and washer 29 Make sure that the pin 1 1 i
9. osition indicator while adjusting zero and span an ammeter can be connected to the terminals 81 and 82 when the associated jumper has been removed The position indicator is operated in a two wire circuit In general the supply voltage amounts to 24 V DC Under consideration of the resistance of the supply leads the voltage at the terminals must be at least 12 V DC but not higher than 45 V DC For instruments designed for application in hazardous areas the installation regulations acc to VDE 0165 are to be observed 4 Operation 4 1 Adjusting the position indicator 4 1 1 Operating direction For a valve travel of 0 to 100 the feedback signal operating direction either gt gt or lt gt can be adjusted to be within a range of either 4 to 20 mA or 20 to 4 mA This range de pends on both the attachment position of the position indicator at the valve direct attach ment on the left hand or right hand side or to the positioner respectively and the type of actuator used models with either spring ex tending or spring retracting the actuator 81 32 82 SCH Ammeter Power supply unit 31 L Fig 6 Electrical connection stem The desired operating direction of the output signal is determined by means of a 7 pin plug located on the PCB see table below The respective operating direction adjusted is indicated by the symbol on the plug facing upwards either
10. s led through the bracket and clamped against the plate 20 Important When the position indicator is at tached to the left hand side of the valve view onto plate 20 actuator on top the pin 1 1 must be clamped against the plate from below whereas it must be clamped against the plate from the top when the position indi cator is mounted to the right hand side of the valve 2 1 2 Attachment to valves with rod type yoke Fig 4 Secure plate 20 with screws 21 to the travel indicator 24 of the plug stem Place mounting plate 28 and clamping plate 26 against the stud bolt 27 and slightly screw them together Shift mounting plate until the middle of plate 20 and the mounting plate 28 are aligned at 50 valve travel and the lever lies horizontally Tightly screw together mounting plate and clamping plate Put in strument on the mounting plate assuring that pin 1 1 is led through the bracket of the plate 20 Tightly screw on position indicator using mounting screw 11 and washer 29 Important When the position indicator is at tached to the left hand side of the valve view onto plate 20 actuator on top the pin 1 1 must be clamped against the plate from below whereas it must be clamped against the plate from the top when the position indi cator is mounted to the right hand side of the valve 1129 11 2 221 121 24 20 Fig 3 Attachment to e g Series 240 ENT Fre NC
11. ture class T6 Max 70 C Temperature class T5 20 C 70 C Effect of ambient temperature lt 0 3 10 Kon lower range value lt 0 3 10 Kon span Ripple of output signal lt 0 3 Travel ranges 1 Positioner attachment 3736 3765 8 60 mm min max 2 Lever 7 71 mm Lever II 10 103 mm Materials Housing Al diecasting plastic coated External parts 1 4571 Al black anodized Degree of protection Direct attachment IP 65 see sect 2 1 Positioner attachment IP 54 IP 65 see sect 2 2 Weight 0 7 kg With max travel 100 32 twisting angle 2 With min travel 100 8 twisting angle 2 Attachment Depending on the travel range of the control valve in case of either direct or positioner at tachment the position indicator requires dif ferent levers 1 the attachment parts of which are a part of the accessories Lever for positioner attachment including in termediate piece pos 31 acc to Fig 5 Order no 1400 6710 and Lever 157 mm for direct attachment Order no 1400 6711 and Lever Il 210 mm for direct attachment Order no 1400 6712 The corresponding lever must be mounted prior to attaching the position indicator to the control valve For this purpose slide the clamping plate 1 2 over the lever 1 and install both on the sensor shaft Afterwards tighten mounting screw Secure enclosed pin 1 1 with nuts 22 a
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