Power Circuit Breakers, GEI-86134 MAINTENANCE MANUAL SUPPLEMENT LOW-VOLTAGE POWER CIRCUIT BREAKERS TYPES AKR/AKRU-30/50, AKRT-50 PER TABLE INTRODUCTION The data in this supplement pertains to the new AKR-30H. Same as the AKR-30 ex cept for modifi 800A AKR-30 and 2000A AKRT-50 frame cations in the following areas: breakers not covered by the ex isting AKR/AKRU-50 maintenance manual (publication G EK-7310A) .
GEI-86134, Power Circuit Breakers BREAKER RATINGS ratings attained by special arc quenchers, closing springs and added insulation. Quencher tops and AKR breakers are available in three frame sizes closing springs carry the same red color used on -- 800, 1600 and 2000 amperes. These values re the AKR-30H.
Power Circuit Breakers, GEI-86134 a. An AKR-30H can be inserted into an AKR-30 DRAWOUT BREAKER compartment. INTERCHANGEABILITY b. An AKR-50H can be inserted into an AKR-50 In general, drawout breakers of the same type compartment. and rating are interchangeable in their equipment compartments;...
GEI-86134, Power Circuit Breakers Fig. 4. AKR-S A-30 breaker 1. Opening spring 2. Rejection bracket the link is too long, the handle stroke cannot BREAKER MAINTENANCE extend the closing spring enough for it to go over center. In this event, use the maintenance handle to complete the spring charging.
Gfl-86134, Power Circuit Breakers ADJUST GAP TO 0.06011 0.020" WITH BREAKER CLOSED CONTACT ADJUSTMENT Type AKRT -50 The contact structure of this 2000A breaker is conceptually identical to the 1600A AKR-50 except that it employs eight stationary main contacts in stead of six.
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Power Circuit Breakers, GEI-86134 1. Movable contact arm 2. Stationary main contact 3. Stationary intermediate contact 4. Stationary arcing contact 5. Driving link 6. Insulating link 7. Coupling pin Fig. 8. AKRT-50 contact structure DRIVING LINK Fig. 9. AKRT-50 Movable contact pivot block...
The 300, 350 and 400A end behind the contact stop) while extending and engaging the spring on the outer end. A suitable sizes require copper adapter bars per Fig. 11. TABLE 3 GE CLF FUSES FOR AKRU BREAKERS NEMA Melting Breaker Fuse Time-...
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Power Circuit Breakers, GEI-86134 Fig. 10. Typical mounting for class "L" fuse on AKRU-30 and -50 breakers ADAPTER BARS (COPPER) Fig. 11. Mounting for 300, 350 and 400A Class J fuses on AKRU-30 breakers...
GEI-86134, Power Circuit Breakers 1. Special 2500A Fuse 2. Disconnect Key 3. Heat Sink 4. Upper Barrier 5. Primary Disconnect Fig. 12. AKRU-50 breaker with s pecial 250oA fuse 4. Remove the heat sink (3). Special 2500A Fuse for AKRU-50 5 .
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Power Circuit Breakers, GEI-86134 1. BREAKER STUD 2. HEAT SINK 3. PRIMARY DISCONNECT ASSEMBLY Fig. 13. Mounting for s pecial 250 0A fuse on AKRU-50 breaker FRONT OF BREA�ER FOR TH I S POLE ONLY, FUSE IS ROTATED 180° FUSE TANGS TO POSIT ION TANG BREAKER POS I T I ONED ON TOP...
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Power Circuit Breakers, GEI-86134 5. Tap Terminal Board 1. Flux shift Trip Device 2. Allen-head Screws 6. Programmer Unit 7. Clamp Bolt 3. Stud Connector 4. Current Sensor Sensor Stud AKR-SA-30 Fig. breaker with SST tri p device A pplication of the Ground Fault element on 4- All components except the neutral sensor are mounted on the circuit breaker.
GEI-86134, Power Circuit Breakers 600- 1600 A 300 -BOO A 100 - 300 A SST phase sensor with tap board Fig. 18. Fig. 19. SST Neutral sensors TABLE 4 SST TRIP CHARACTERISTICS SST PR OGRAMMER ADJUSTMENT RANGE (Set Points) X • Trip Rating in Amperes Long Time •Sensor Tap...
Power Circuit Breakers, GEI-86134 TROUBLESHOOTING When malfunctioning is suspected, the first step in troubleshooting is to examine the circuit breaker and its power system for abnormal conditions such Breaker tripping in proper response to over currents or incipient ground faults. Breaker remaining in a trip-free state due to mechanical interference along its trip shaft.
GEI-86134, Power Circuit Breakers Fig. 21. SSTjECS test set, cat. TAK-TSI CAUTION: USING THE SST TEST SET NEVER DISENGAGE HARNESS CONNECTOR FROM THE PRO GRAMMER UNIT ON A BREAKER THAT The TAK-TSl Test Set is a portable instrument IS ENERGIZED AND CARRYING LOAD designed for field-checking the time-current char...
Power Circuit Breakers, GEI-86134 condary disconnect block. Also check FALSE TRIPPING - BREAKERS EQUIPPED WITH for continuity from the breaker-mounted GROUND FAULT neutral secondary disconnect block through to the female harness connector When nuisance tripping occurs on breakers (terminals L and N). equipped with the Ground Fault trip element, a probable cause is the existence of a false "ground"...
GEI-86134, Power Circuit Breakers CRANK BREAKER RESET CLOSED POS I T I ON Ll NKAGE MAI N SHAFT TRIP PADDLE FRONT SIDE � VIEW VIEW Fig. 22. Flux shift trip device and operating linkages 0. 125 0. 015 just gap to inch+ inch.
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Power Circuit Breakers, GEI-86134 Bottom view Top view 4. Trip shaft 1. Actuator 2. Trip rod adjuster end 5. Actuator arm 3. Trip paddle 6. Reset linkage Fig. 23. Flux shift tri p device com ponents TRIP PADDLE IN " "...
GEI-86134, Power Circuit Breakers c\IB c\IC PROGRAMMER FLUX SHIFT UNIT TRIP DEVICE ,--- BREAKER r -� , b BACK FRAME � (TO SCR ANODE) LEFT POLE CURRENT WHITE SENSOR BLACK WHITE BLACK WHITE BLACK HARNESS PR O GR AM ME R CO NN EC TO R CONNECTOR (AMP 201298-1)
Power Circuit Breakers, GEI-86134 ci>B ci>C PROGRAMMER FLUX SHIFT UNIT TRIP DEVICE BACK FRAME � � BLACK WHITE BLACK NEUTRAL SENSOR WHITE DISCONNECT - - 1 BLACK LINE WHITE BLACK HARNESS PR O GR AM M ER CO NN E CT OR CONNECTOR EQUIPMENT -MOUNTED (AMP 201298-1)
Power Circuit Breakers, GEI-86134 ECS current sensors on AKRU-4A-30 Fig. 31. breaker TABLES ECS TRIP CHARACTERISTICS X = Trip Rating ECS PROGRAMMER ADJUSTMENT RANGE (Set Points) in Amperes =Sensor Rating Long Time Short Time Frame Breaker Instantaneous Size Pick (=L) Time Pickup Time...
Power Circuit Breakers, GEI-86134 .I .I .l .I . • I 1 I 1 11 MULTIPLES OF LONG-TIME PICKUP {L) 1110 I I I II 1 ..! Uf I I I • 50 10 7G 1010! Long-time Delay Bands Maximum Total...
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GEI-86134, Power Circuit Breakers MULTIPLES OF LONG-TIME PICKUP ( L) I .7 .1 . • U UI ..� n � I I I aoto! 1 10 .• 7110 1000 5110 3110 2110 Long-time ..Delay Bands ..
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Power Circuit Breakers, GEI-86134 MULTIPLES OF CURRENT SENSOR TAP (X) • I � � AK-15/25 Ground Fault Pickup Points • AKR-30 Ground Fault AK-50 Ground Fault Pickup Points AKR-50 Pickup Points I.O)( • 1.2X �. Maximum Maximum Ground Fault ay Bands Intermediate lntermedi ate Minimum...
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GEI-86134, Power Circuit Breakers .• MULTIPLES OF CURRENT SENSOR TAP (X) · • · � � •• � � " " · · ·' .• NOTE MULTIPLES OF C U RRENT SENSOR TAP 4th wire Ground sensor tap must be set some phose sensor top AK/ AKR LOW-VOLTAGE POWER CIRCUIT BREAKERS GES-60358...