GEK-86038 TEMPERATURE RELAY TYPES: IRT51E IRT51F IRT51G IRT51H DESCR IPTIO N INT RODUCTION �- The type IRT temperatu re sensing rel ays a re designed fo r use with singl e el emer th ree l ead , resistance tem pe ratu re detecto rs ( RTD) . M odel s a re av ail abl e for use wi the fol l owing specific type RTD:...
GEK-86038 the main induction disk u nit, a s shown in Figure 9. The rel ay operates to c l o se the normal l y-open output c ontact s wheneve r the detected tem perature exceeds the set ' v al ue .
GEK-86038 It is impo rtant to note that these type IRT relays detect actu al tempe ratu re , not rise above ambient . The temperatu re setting sho uld be made on the basis of long term trends in ambient tem pe ratu re . RATINGS The o pe rating u nit of the type IRT relays has a center ta pped coil that permits o peration at eithe r 1 20 o r 24 0 volts AC * .
Page 8
GEK-86038 cu r rents ranging f rom 0 . 2 2 . 0 am ps DC at the m1n1m um control voltage. If this tap is u sed with trip co il s requi ring m o re than 2 . 0 am ps , there i s a po s sibility, .
GEK-86038 The auxiliary circuit may be reset manually by pushing u pwa rd on the reset rod, located on the bottom left side of the cover. O r it may be reset electrically from a' r emote location by connecting a control switch acro s s terminals 1 9 and 20. Or the relay may be made self-re setting by sho rting terminals 1 9 and 20 together.
GEK-86038 TABLE 5 BURDEN FOR IRT5 1 E 0. 2 7. 0 0.1 3 TABLE 6 BURDEN FOR IRT5 1 F AUXILIARY CIRCUIT STATE PICKED UP NOT PICKED UP VO L TS CONTINUOUS MOMENTARY 1 1 0 5 0/6 0 7 8 0 ohms 2 6 5 0 ohms infinite...
GEK-86038 ..The back of the case ha s stu d s mo unted in an outer block. These stu d s a re used for' making the external wiring connections to the relay case . A removable connection plug connect s the o uter block to an inner block which is connected to the internal wiring of the relay.
Refer to the external connections diagrams shown in Fig ures 1 0, 1 1 and 1 2 for the connections to be used for diffe rent voltage so u rces. See Table 1 fo r the relay v o lta ge ratings. 1 20 volt A C Ope ration: Coil H 1-H2 must be placed in pa rallel with coil H3-H4.
Page 13
G E K-86038 Remove the screw from the other ta p and place it in the left stationa r � contact. Du ring relay o peration , ta p screws should not be in both taps at the s ame time. ·If they are , picku p will occur at the higher tap value.
GEK-86038 relay senses temperatu re below pre- selected reset temperatu re , causing the right-hand contact (I RT R ) to close , and The relay i s reset by any one of the three method s listed below:. METHOD 1: Reset can be accompli shed by pushing u pward on the reset rod ocated at the bottom , left side of the relay cover.
GEK-86038 * should be identical for all three leads. The resistance of each lead to relays us�d with 10 ohm RTDs must not exceed 0.25 ohm (1.0 ohm to relays used with 100 ohm A decrease in the operating point of the re 1 ay of up to 0. 8 o C o;"...
GEK-86038 MECHANICAL I NSPECTION AND A DJUSTMENTS There sho uld be no noticeable friction when the disk is slowly rotated clockwise . The disk sho uld retu rn by itself to its rest position against the right stationary contact o r moving contact sto p . If a tendency to bind o r excessive f riction is evident , check fo r o bstructions to the disk travel.
GEK-86038 The wipe on each n o rmally-o pen c ontact sho uld be a p pro ximately 0.005 inch . This ga p can be checked by inse rting a 0. 005 inch feeler g age between the armat u re and the pole piece a nd o pe rating the a rmatu re by h and. The no rmally- o pen c ontacts sho uld make with the 0.
Page 19
GEK-86038 Relays to be used with direct current power should be tested using good direct current power supply, not full wave rectified power. Unless the rectified power supply well filtered, that is, there is less than 5% ripple, the IRT auxiliary circuits may behave slightly different when tested with a power supply that is substantially different than the system power supply.
Set the adjustable ta p ( slide band ) on R2 to a position at the center of the a djustable range of the resisto r. a r ge r .. diameter wire , with a ma ximum wire Using AWG No. 12 o r...
Page 21
GEK-86038 120oc temperature selection dial if resistor "C" chosen, temperature that is associated with the resistance value chosen if a valiJe other than resistor "C" is selected. The left contacts (IRT L ) should ±2oc of the selected temperature dial setting. This completes close within the overtemperature calibration procedure.
GEK-86038 RENEWAL PARTS Sufficient q u antities of renewal pa rts should be kept in stock for the prompt replacement of any that a re wo rn, broken o r d amaged . When o rdering renewal pa rts , add ress the nea rest sales o ffice of the General Electric Company.
Page 23
GEK-86038 • • L I S T OF TA BLES � c TABLE PAGE NO . TITLE Relay Model Description Table Target Seal-in Unit Ratings Auxiliary Telephone-Type Relay Interrupting Ratings Operating Unit Burdens Burden for IRT51E - Target Seal-in Unit Burden for IRT51F - Auxiliary Circuit Burden for IRT51G and IRT51H - Target Seal-in Unit and Auxiliar y Circuit...
Page 24
GEK-86038 • • LIST OF ILLUSTRATIONS FIGURE PAGE � Type IRT51G and IRT51H Relay, Front View • • • • Type IRT51G and IRT51H Relay, Right Side View Type IRT51G and IRT51H Relay, Left Side and Back View • • •...
Page 25
GEK-86038 UPP ER PIVO T TEMPERATURE CONTACT DIAL TARGET SEAL-IN INDUCTION DISK SPRING G and Front Figure (050283-1) Type IRT51 IRT51 Relay, View Figure l Type IRTSIG and IRT51H Relay, Front View (050283-1)
Page 26
GEK-86038 R1-SLIDE BAND DISK Figure 2 (050283-2) Type IRT51 G and I RT51 H Relay Right Srde Vrew Figure 2 (050283-2) Type IRT51G and IRT51H Relay, Right Side View...
Page 27
G E K - 86 0 38 LA T C HIN G F ig u re 3 (05 0 28 3 - 3) T y p e I R T SJ G an d IR T SJ H R e l a y , l e f t S i de a nd B ac k V i ew...
Page 28
GEK-86038 " FITTING 0 RING RING 3 LEAD WIRE� PIPE SIZ E P I P E SIZE BRASS REDUCING BUSHING PIPE FITTING Figure ( 0285A6731-0) R esistance Temperature D e tector Assembl y...
Page 29
GE K- 86 03 8 • ' \. . AR M AT UR E AR M OPE RATIN G RE SI DUAl SC RE W LO CK NU T PO LE PI EC E ph on e Re la y...
Page 30
GEK-86038 CONNECTING PL UG MAIN BRUSH CONN ECTING BLO CK AUXIL IARY SHORT IN G NOTE: AFTER ENGA G ING AU XILIARY BRUSH CONNECTING PLUG TRAVELS INCH BEFORE ENGAG ING T HE MAIN BRUSH ON T HE T ERMINAL BL OCK (80 25039) Drawout Case, Contact Assembly Figure...
Page 31
GEK-86038 " •, UPPER COILS H3 H4 " * =SHORT FINGER Figure 7 (0285A6213-0) Internal Connections Diagram for the Type IRT51E Relay...
Page 32
GEK-86038 UPPER COILS REMOVE IF NOT USED =SHORT FINGER AUXILIARY TELEPHONE RELAY TARGET Figure 8 0285A6214-2 Internal Connections Diagram for the Type IRT51F Relay...
Page 33
GEK-86038 I RT U P P E R CO I L li 4 H� M 5 :: Mbl l iJ AL R E 5 E T '5'1 / I TC H Q.P :: A U X I L I A RY OPE R ATI N G U N IT * = S HO RT F l N G E R U N I T...
Page 34
T E R rA J rJ A L l:l O A R D F i gure 10 (018488 7 79 - 1 , Sh. 1 ) Externa l C onnect i ons D i a gr am f or t he Type IRT51 E Rel ay...
Page 36
GEK-86038 c· S O J R C E: \ C O N T R O l . P O W ER OR f' O H N T I A L T R A N S " O R ME:. R l C O WW C T I O N C O N N E C T I O N F O R...
Page 38
GEK-86038 AC S O U R C E <C O N T R OL P O W E R O R P O T E N T I A L T R A N S F O R M E R l C O N NE C T I O N C O N N E C T I O N ! 2 0 V...
Page 44
GEK-86038 O F S I M U L AT E D R T D R E S I S T A N C E T E M P E R AT U R E V E R S U S ®...
Page 46
GEK-86038 • .. . FA H R E N H E I T T O C E N T I G R A D E C O N V E R S I O N C H A R T �...
Page 48
GEK-86038 P A N E L L OC A T I ON S EM I - F L U S H S U R F A C E ( 2 ) 5 / 1 6 - 1 8 S T U D S 6 .
Page 50
GEK-86038 6 . 6 2 5 < 0 . 3 1 2 3 / 8 S T UD 26 1 MM M T G . S C R E W S N U M B E R I NG 0 0 0 0 0 G L A S S 0 0 0 0 0 1 .