Summary of Contents for TMC21B

Page 1: ...INSTRUCTIONS GEK 49940B THERMAL OVERCURRENT RELAY TYPES TMC21B TMC23B GENERAL ELECTRIC Courtesy of NationalSwitchgear com ...

Page 2: ...ISMIC INSTANTANEOUS UNIT 7 HIGH SEISMIC TARGET 7 CONSTRUCTION 7 RECEIVING HANDLING AND STORAGE ACCEPTANCE TESTS 8 8 VISUAL INSPECTION TESTING FACILITIES POWER REQUIREMENTS GENERAL THERMAL UNIT 9 9 9 9 HIGH SEISMIC INSTANTANEOUS UNIT 10 HIGH SEISMIC TARGET 10 INSTALLATION 11 PERIODIC CHECKS AND ROUTINE MAINTENANCE 11 CONTACT CLEANING 11 SYSTEM TEST 12 RENEWAL PARTS 12 LIST OF FIGURES 13 COVER 80435...

Page 3: ...ICATION The TMC relays described here are designed to provide thermal overload and short circuit protection for motors The relays are not intended for use directly in primary motor circuits They should always be applied with current transformers CTs so that they will be self protecting on primary short circuits The CTs will saturate before excessive secondary currents can be reached The relay ther...

Page 4: ...TURE RATING OF MOTOR CORRECTION FACTOR Continuous 1 15 service factor Continuous 1 0 service factor Short time 60 minutes Short time 30 minutes Short time 15 minutes Short time 5 minutes 1 0 0 9 0 8 0 75 0 7 0 6 The thermal unit tripping current is adjustable over the range of The relay is calibrated at coil rating current with a 10 0 90 to 110 of the nominal coil rating 40 C to just trip at the I...

Page 5: ...rating one second rating etc TABLE I CONTINUOUS RATING AMPS HIGH SEISMIC INSTANTANEOUS UNIT AMPS ONE ftt SECOND RATING AMPS ft RANGE AMPS RANGE K 10 2 6 30 LOW 67 000 6 150 260 19 6 30 150 HIGH tt The range is approximate which means that the 6 30 30 150 may be 6 28 28 150 one ampere overlap between the maximum low setting and the minimum high setting higher range since it has the higher continuou...

Page 6: ...MC21B type relay The burden of The volt ampere burden of the TMC21B at five amperes is approximately equal to K divided by the square of the current rating where K is 325 for 60 hertz and 305 for 50 hertz The volt ampere burden of the TMC23B at five amperes is approximately equal to K divided by the square of the current rating where K is 295 HIGH SEISMIC INSTANTANEOUS UNIT The High Seismic instan...

Page 7: ...acteristic curve for the instantaneous unit is shown in Figure 9 HIGH SEISMIC TARGET The target has an operating coil tapped at 0 2 and 2 0 amperes The relay is shipped from the factory with the tap screw in the higher ampere position CONSTRUCTION The relay case is suitable for either surface or semiflush panel mounting and an assortment of hardware is provided for either mounting The cover attach...

Page 8: ...ront top right picks up it raises a target that latches up and remains exposed until The same reset rod that releases the left target also releases the instantaneous unit target When the instantaneous unit it is released RECEIVING HANDLING AND STORAGE These relays when not included as a part of a control panel will be shipped in cartons designed to protect them against damage Immediately upon rece...

Page 9: ...onnections For further information on these test plugs refer to Section 7332 in the General Electric Apparatus Handbook or contact the nearest General Electric Sales Office POWER REQUIREMENTS GENERAL All devices operating on alternating current AC are affected by Since non sinusoidal waveforms can be analyzed as a frequency fundamental frequency plus harmonics of that fundamental frequency it foll...

Page 10: ... for the range in See Figure 4 range which it is to operate higher range since the higher rating Whenever possible use the has the higher continuous The instantaneous unit has an adjustable core located at the top of the unit as shown in Figure 1 To set the instantaneous unit to a desired pickup loosen the locknut and adjust the core the core clockwise decreases the counterclockwise increases the ...

Page 11: ...d at an interval of from one to two years To substitute a new current coil in the thermal unit the procedure should be as follows Remove the coil leads from Terminals 5 and 6 1 Loosen the three mounting screws and remove the retaining plate see Figure 2 2 Lift out the present coil and substitute the replacement for it taking care that the coil is mounted with the two locating pins on the lower sid...

Page 12: ...NEWAL PARTS It is recommended that sufficient quantities of renewal parts be carried in stock to enable the prompt replacement of any that are worn broken or damaged When ordering renewal parts address the nearest Sales Office of the General Electric Company specify the quantity required the name of the part wanted and the complete model number of the relay for which the part is required 12 Courte...

Page 13: ...ctions for Type TMC Relay 18 5 Time Current Characteristic Curve for Type TMC21B Relay 6 19 Time Current Characteristic Curve for Type TMC23B Relay 7 20 Transient Overreach Characteristics of the High Seismic Instantaneous Unit 8 21 Time Current Characteristics of the High Seismic Instantaneous Unit 9 2 2 Outline and Panel Drilling for Types TMC21B and TMC23B Relays 10 23 Revised since last issue ...

Page 14: ...GEK 49940 ADJUSTABLE POLE PIECE TARGET NSTANTANEOUS UNIT TARGET SEAL 1 N UNIT R E S E T Figure 1 8043502 TMC21B Relay Front View 14 Courtesy of NationalSwitchgear com ...

Page 15: ...GEK 49940 INSTANTANEOUS UNIT ADJUSTABLE POLE PIECE RESET ROD 8043503 TMC21B Relay Rear View Figure 2 15 Courtesy of NationalSwitchgear com ...

Page 16: ...TARGET _ _ TARGET SEAL IN UNIT INSTANTANEOUS UNIT RESET LEVER OPERATING GOIL COMPENSATING BIMETAL ADJUSTMENT LOCKING SCREW RESET ROD ADJUSTING SCREW STATIONARY CONTACT MOVABLE CONTACT BRUSH Figure 3 8007955 Thermal Unit with Current Coil and Reset Rod Removed 16 Courtesy of NationalSwitchgear com ...

Page 17: ...v y Y V Y Y V TvJ INSTANTANEOUS SETTINGS o o o o SHOWN IN LOW RANGE CONNECT E TO 8A AND T TO 8 FOR THE HIGH RANGE 5 3 7 o o o o 8 6 2 4 SHC RT FINGER Internal Connections for Type TMC21B and TMC23B Relays Figure 4 0273A9 5 5 6 17 Courtesy of NationalSwitchgear com ...

Page 18: ... a 52 o o Tt 5 r 9 t 450 7 LEGEND 49 THERMAL UNIT 50 INSTANTANEOUS UNIT T TARGET 52 CIRCUIT BREAKER TC TRIP COIL a AUXILIARY CONTACT CLOSED WHEN BREAKER IS CLOSED MOTOR Figure 5 0275A4381 Typical External Connections for Type TMC Relay 18 Courtesy of NationalSwitchgear com ...

Page 19: ...O 4 UJ 00 OO 5 CD NT f b 5 t i r i 1 a 1 T cr i t i o o H r O rx 7 9 CO z X 1 Q 3 X 2 XI o o LU in 1 r t t 1 T I 1 I 1 I f I r 1 O 1 i i i I 1 1 i r 1 O o o o o o o o o o o o CO C J in sr u S3 b3 MV 1100 031Vd N30d3d 0285A8975 Time Current Characteristic Curve for Type TMC21B Relay Figure 6 Revised since last issue 19 Courtesy of NationalSwitchgear com ...

Page 20: ...Q_ 8 W P o 8 g O o OA w o Os o CD 00 CO LO o o o o o o o o o o o o o o o o oo CO UO o OvJ T i S3d3dW 1103 031Vd iN30d3d Figure 7 0418A0800 Time Current Characteristic Curve for Type TMC23B Relay 20 Courtesy of NationalSwitchgear com ...

Page 21: ...i 00 i VD I i 4 H LQ tsj MO s t I cn o D 1 X w o M 3 3 W rr UJ Q l I l i t t t z C 5 m H i i 3o c f HI SEISMIC MINIMUM PICK UP t t t r UJ i QC NJ a VO UJ rr VO 0 4 1 o O t t 3 O rr CD CD i 3 l 1 20 CD i CD O D C o I I w 3 1 1 1 G i 1 o n H tf rr D l to 4 f CD o MAXIMUM PICK UP HI SEISMIC rr i CD i H CD rr H 10 o o 60 50 90 30 20 40 70 80 in ANGLE IN CEGREES LAG o in rr CD ...

Page 22: ...CO u _ o 5 cO LAJ LU 5 o _ to H O sS ffi 3 8 O LU to in o m to 8 CM o o o S0N003S NI 3WI1 dOMOId Figure 9 Time Current Characteristics of the Seismic Instantaneous Unit 0208A8695 1 High 22 Courtesy of NationalSwitchgear com ...

Page 23: ...6MM t CUTdUT 76MM I 4 4 375 1 1 1 MM 8 812 223MM 3 906 99MM I f 4 281 1 08MM I oQo 0 o ot 1 468 37MM i f 718 2 5C 2 843 72MM 18MM 6MM 218 218 500 5 25 i 5MM 5MM i 12MM TYPICAL 5 687 133MM PANEL 144MM 3 4 DRILL 10 HOLES 19MM PANEL DRILLING FDR SEMI FLUSH MOUNTING FRDNT VIEW PANEL DRILLING FDR SURFACE MOUNTING FRONT VIEW CASE 5 16 18 STUD 3 0 I 76MM VIEW SHOWING ASSEMBLY OF HARDWARE FOR SURFACE MTG ...

Page 24: ...å å å å 3RZHU 0DQDJHPHQW 215 Anderson Avenue Markham Ontario Canada L6E 1B3 Tel 905 294 6222 Fax 905 201 2098 www ge com indsys pm Courtesy of NationalSwitchgear com ...

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