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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  special  250oA  fuse 

Special  2500A  Fuse  for  AKRU-50 

This fuse provides a  melting time-current char­

acteristic that coordinates with  1600A trip devices. 

Compared physically  with  a  2500A  NEMA  Class  L 

fuse,  the  special  fuse  is  more  compact  (shorter); 

its  tangs  are  specially  configured  and  offset  to 

achieve  the  required  pole -to-pole  fuse  spacing;  a 

special primary disconnect assembly mounts directly 

on the  outboard  tang  of the  fuse.  Considering  their 

unique  mounting  provisions,  when  replacing  these 

fuses the following  procedure  should  be  adhered to 

(Refer to Fig.  12): 

1.  Remove  the  primary  disconnect  assembly 

from the fuse tang,  accomplished by first  loosening 

the two keys  (2)  via  their  holding  screw  and  pulling 

them  upward  and out.  After the keys  are removed, 

pull the disconnect assembly off the  end of  the fuse 

tang. 

NOTE: 

This  removal  does  not  disturb  the 

disconnect's  clamping  force  adjustment. 

2.  Remove the  upper barrier  (4) . 

3.  Detach the  inboard  end  of the fuse by remov­

ing  the  two 

1/2 

inch 

-

13  bolts.  A  ratchet  and 

socket with a  short extension will be required. 

12 

4.  Remove the heat sink  (3). 

5.  Remove the  fuse. 

6.  Install  the  new  fuse  by  reversing  the  dis­

assembly procedure.  Ensure that the mating faces 

of the fuse  and heat sink are  clean. 

CAUTION: 

WHEN 

REPLACING 

THE 

FUSE  IN  THE  LEFT  POLE  (FRONT 
VIEW)  OF  THE  BREAKER,  NOTE  PAR­
TICULARLY 

THAT 

THIS 

FUSE 

IS 

MOUNTED  DIFFERENTLY  THAN  THE 
OTHER  TWO  FUSES. 

AS  SHOWN  IN 

FIG.  14,  FOR  THIS  PHASE  THE  FUSE 

IS  ROTATED  180  DEGREES  ABOUT  ITS 

AXIS  SO  THAT  ITS  INBOARD  TANG  IS 

POSITIONED  BENEATH  THE  BREAKER 

STUD. 

THIS  TANG  IS  OFFSET  WITH 

RESPECT  TO  THE  OPPOSITE  END  (SEE 

FIG.  13,  SO  THAT  ROTATING  THE  FUSE 

DOES  NOT  ALTER  THE  POSITION  OF 

THE  PRIM ARY  DISCONNECT. 

Open  Fuse  Lockout  Device 

Refer to GEK-7310A,  page 31. 

www 

. ElectricalPartManuals 

. com 

Summary of Contents for AKR-4-30

Page 1: ...he AKR breaker models and trip devices listed in Table 1 TABLE 1 Frame Breaker Type Mounting Trip Device Type Size Amp Stationary Drawout ECS SST AKR 4 30 30H AKR 4A 30 30H X AKR 5 30 30H AK 5A 30 30H X BOO AKRU 4A 30 X AKRU 5A 30 X AKR 4 50 50H AKR 4A 50 50H X AKR 5 50 50H AKR 5A 50 50H X 1600 AKRU 4A 50 X AKRU 5A 50 X AKRT 4 50 AKRT 4A 50 X 2000 AKRT 5 50 AKRT 5A 50 X Integrally fused types GENE...

Page 2: ...acement of Current Sensors Flux Shift Trip Device Cabling Diagrams Ground Fault Defeat Cable Type ECS Overcurrent Trip Device Components Trip Characteristics Cabling Diagram ECS SST Time Current Curves 3 3 4 5 6 6 6 6 7 R B 10 10 10 10 12 12 14 14 16 17 18 19 19 20 22 23 24 24 25 26 27 These instructions do not purport to cover all details or variations in equipment nor to provide for every possib...

Page 3: ...10A as the general op erational information source Complementing the above new material this supplement includes additional information to ex pand and updateex istingG EK 7310A subject matter where appropriate Ex amples are revision of the operating handle adjustment procedure and reduc tion of the AKRU 50 minimum fuse size from 800A to 450A CONSTRUCTIONAL DIFFERENCES The features which distinguis...

Page 4: ...each breaker carries a specific rating which is determined by the current sensor ampere rating or tap setting of the trip device with which it is equipped EXAMPLE An AKR 5A 30 breaker with SST sensor tap set on 100A is rated 100A Short circuitratings vary with the applied system voltage On 240 V systems they are also dependent upon whether the overcurrent trip device contains an instantaneous trip...

Page 5: ... POSITIONS Fig 2 Non interchangeability rejection hardware arrangements in drawout com partments for breaker Types AKR 30j30Hj50j50H AKRT 50 and AKRU 30 50 Power Circuit Breakers GEI 86134 a An AKR 30H can be inserted into an AKR 30 compartment b An AKR 50H can be inserted into an AKR 50 compartment The rejection hardware prevents the conver se of a and b Figure 2 shows the rejection pin and brack...

Page 6: ...g the handle stroke cannot extend the closing spring enough for it to go over center In this event use the maintenance handle to complete the spring charging The breaker can then be closed and opened preparatory to further shortening of the link If the link is too short one stroke charging is not possible However more than one stroke will charge the springs v CONTACT MAINTENANCE Breakers subjected...

Page 7: ...le consists of a single movable contact arm acting against five stationary contacts arranged vertically as shown in Fig 5 Proceeding from top to bottom Power Circuit Breakers GEI 86134 1 Movable contact arm 2 Stationary main contact 3 Stationary arcing contact Fig 6 AKR 30H contact structure the first two contacts serve as the arcing contacts and the bottom three are the mains There are no interme...

Page 8: ...onstructionally however the upper stud assembly movable contact arms and pivot block are unique to the AKRT 50 See Figs 8 and 9 The two movable contact arms are pin coupled to a metal driving link whose opposite end is threaded and screws directly into the insulating link This arrangement omits the wrench operated wipe adjustment stud provided on the AKR 30 and 50 frames Instead wipe is adjusted b...

Page 9: ...ture 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 DRIVING LINK Fig 9 AKRT 50 Movable contact pivot block 9 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...

Page 10: ...of a length of 1 16 inch diameter steel wire The two movable contact arms 4 are removed by drifting out pin 10 connecting them to the in sulated coupling 11 Right angle tru arc pliers are needed to remove and replace the tru arc re tainer on the end of the pin Next remove the fastening screws washers springs and pivot pin from the pivot below When replacing the arms ensure that all spacers springs...

Page 11: ...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 11 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...

Page 12: ...rd and out After the keys are removed pull the disconnect assembly off the end of the fuse tang NOTE This removal does not disturb the disconnect s clamping force adjustment 2 Remove the upper barrier 4 3 Detach the inboard end of the fuse by remov ing the two 1 2 inch 13 bolts A ratchet and socket with a short extension will be required 12 4 Remove the heat sink 3 5 Remove the fuse 6 Install the ...

Page 13: ...SE TANGS POS IT IONED ON TOP OF BREAKER STUD FOR TH IS POLE ONLY FUSE IS ROTATED 180 TO POSIT ION TANG BENEATH BREAKER STUD TANG BOLT HOLES IN USE 2500A F USE CAT NO GF9F2500 AK PRI MARY D ISCONNECT A SSEMBLY SEE FIG I3 MOUNTS D I RECTLY ON OUTBOARD FUSE TANG Fig 14 Plan view of AKRU 50 breaker showing 2500A fuse tang positions 13 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...

Page 14: ... by the short time and instantaneous elements and the third for ground fault The latter is omitted on units without ground fault Each target pops out when its associated trip element operates to trip the breaker After a trip the popped target must be reset by hand However neglecting to reset does not affect normal operation of any trip element or prevent the breaker from being reclosed Current Sen...

Page 15: ...those on the neutral sensor must be correspondingly positioned Flux Shift Trip Device a low energy electro magnetic device which upon receipt of a trip signal from the programmer unit trips the breaker by actuating the trip shaft See Fig 22 All components except the neutral sensor are mounted on the circuit breaker The phase sensors are located on the breaker s back frame The pro grammer unit and ...

Page 16: ...ts Long Time Short Time GROU ND FAULT Instantaneous PickCD L Time Pickup Time Pickup Pickup Time Delay Delay Delay Multiple Band Multiple Band Multiple Multiple Band ofX Seconds ofL Seconds ofL ofX Seconds 3 4 5 4 5 6 6 8 10 L 8 1 0 1 2 X Maximum Maximum Maximum 6 7 8 22 or 0 35 4 5 6 0 30 9 1 0 Intermed Int rmed 8 10 12 L 25 3 4 Intermed 1 1 X 10 1 75 2 0 21 5 6 0 165 2 25 2 5 7 X Minimum 3 4 L M...

Page 17: ...proper Testing is performed by either of two methods 1 Conduct high current single phase tests on the breaker using a high current low voltage test set NOTE For these single phase tests spe cial connections must be em ployed or SST breakers equipped with Ground Fault Any single phase input to the ground differential transformer will generate an unwanted ground fault output signal which will trip t...

Page 18: ...ached to the breaker or may be completely re moved from it 18 CAUTION NEVER DISENGAGE THE HARNESS CONNECTOR FROM THE PRO GRAMMER UNIT ON A BREAKER THAT IS ENERGIZED AND CARRYING LOAD CURRENT THIS WILL OPEN CIRCUIT THE CURRENT SENSORS ALLOWING DANGEROUS AND DAMAGING VOLT AGES TO DEVELOP Test scope 1 Verify the time current characteristics and pickup calibration of the various trip elements 2 Verify...

Page 19: ...onnected see cabling diagram Fig 27 In particular 1 Verify that the neutral sensor has the same rating and tap setting as the phase sensors 2 Check continuity between the neutral sensor and its equipment mounted se Power Circuit Breakers GEI 86134 condary disconnect block Also check for continuity from the breaker mounted neutral secondary disconnect block through to the female harness connector t...

Page 20: ...ss for the next trip signal The trip device requires only one adjustment the trip rod length As shown in Fig 24 the clear ance between the trip rod end and the trip shaft paddle is gaged by a 0 125 inch diameter rod Ad 20 just gap to 0 125 inch 0 015 inch To adjust open the breaker and restore the breaker mechanism to its Reset position Loosen the jam nut rotate the adjuster end until the proper g...

Page 21: ...4 Trip shaft 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 MECHANISM RESET POSITION JAM NUT 0 125 DIA ROD Fig 24 Trip rod adjustment 6 21 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...

Page 22: ...ECTOR PROGRAMMER CONNECTOR AMP 201298 1 AMP 201297 1 Fig 25 Cabling Diagram SST without ground fault c IA c IB c IC PROGRAMMER UNIT A A A BREAKER _ _ 4 BACK FRAME r b b 1 FLUX SHIFT TRIP DEVICE LEFT POLE CURRENT SENSOR I WHITE BLACK WHITE BLACK WHITE I I I I I I LOAD l_ ____j PROGRAMMER CONNECTOR AMP 201297 1 Fig 26 Cabling Diagram SST with ground fault on 3 wire load w w w E l e c t r i c a l P a...

Page 23: ...NTED NEUTRAL SENSOR CONNECTOR PROGRAMMER CONNECTOR AMP 201298 1 AMP 201297 1 4 WIRE LOAD Fig 27 Cabling Diagram SST with ground fault on 4 wire load MALE END FEMALE END Fig 28 Cabling diagram with Ground Fault Defeat Cable inserted between breaker harness ANY SST PROGRAMMER UNIT WITH GROUND FAULT ELEMENT and SST Programmer Unit for use during single phase high current low voltage testing 23 w w w ...

Page 24: ...each of the tabulated ampere ratings which span the same range as SST 4 Neutral sensors are not required because there is no Ground Fault function In all other respects the ECS trip device system operates and can be treated identically to SST This includes circuitry size construction com ponent location programmer unit set points per formance characteristics operating range quality reliability and...

Page 25: ...y Rating Multiple Band Multiple Band Multiple ofX Seconds ofL Seconds ofL 100 150 225 3 4 5 300 400 6 8 10 L 600 800 Maximum Maximum 22 0 35 or 300 400 600 6 7 8 Intermed Intermed 4 5 6 800 1200 1600 9 1 0 I 10 1 75 2 0 21 8 10 12 L 1 1 X Minimum 2 25 2 5 Minimum 4 3 4 L 0 095 800 1200 1600 2000 CD Pickup tolerance is _ 9 Pickup tolerance is _ 10 Time delay shown at 600 of long time pickup setting...

Page 26: ...IFT TRIP DEVICE PROGRAMMER UNIT 1 o o o 48V de WHITE BLACK WHITE TO SCR ANODE 1 BL A C K I I LOAD WHITE BLACK J HARNESS CONNECTOR PROGRAMMER CONNECTOR AMP 201298 1 AMP 201297 1 Fig 32 Cabling diagram for ECS TriP Device Fig 33 ECS current sensor w w w E l e c t r i c a l P a r t M a n u a l s c o m ...

Page 27: ...EcsTM SOLID STATE OVERCURRENT TRIP DEVICE I GES 6032A X Cumnt Sensor Rating Amperot AKR 30 AKR 50 AKRT 50 AK 75 AKR 75 AK AKR 1 00 1 00 1 50 225 300 400 600 800 300 400 600 800 1 200 1 600 800 1 200 1 600 2000 1 200 1 600 2000 3000 1 200 1 600 2000 3000 3200 1 600 2000 3000 4000 Long time delay Short time delay ond Instantaneous Time current Curves Curves apply at 50 60 Hertz from 20C to 70C Progr...

Page 28: ...200 14 000 1 600 1 8 000 AKTiAKRT 50 1 600 1 6 000 2000 20 000 G E N E R A L fJ E LE CT R I C j AK AKR LOW VOLTAGE POWER CIRCUIT BREAKERS ssT TM SOLID STATE OVERCURRENT TRIP DEVICE I GES 60338 Current Sensor Taps Amperes AK 1 5 AK 25 AKR 30 AK AKR 50 AKT AKRT 50 AK 75 AKR 75 AK AKR lOO 70 100 150 225 70 100 1 50 225 or 200 300 400 600 100 150 225 300 or 300 400 600 800 300 400 600 800 or 600 800 1...

Page 29: ... SOLID STATE OVERCURRENT TRIP DEVICE AK 1 5 A K 25 AKR 30 Current Sensor Tops Amperes 70 1 00 1 50 225 70 1 00 1 50 225 or 200 300 400 600 1 00 1 50 225 300 o r 300 400 600 800 A K AKR SO 300 400 600 800 or 600 800 1 200 1 600 Ground Trip Time current Curves Curve5 opply ot 50 60 He rtt From 20C ro 70C Programmer Ambient 7X Maximum 7 v lntermediate 7 7v1 v Minimum I GES 6034A Programmer Set Points...

Page 30: ... l 1 1 J JL L L J 1 cl F i 1 I L NOTE 4th wire Ground sensor tap must be set some OS phose sensor top G E N E R A L E L E CT R I C I X Current Sensor Taps Amperes AKT AKRT 50 800 1 200 1 600 2000 AK 75 AKR 75 A K AKR 1 00 I 200 1 600 2000 3000 1 200 1 600 2000 3200 1 600 2000 3000 4000 2 4 a a I z a a I MULTIPLES OF CURRENT SENSOR TAP X AK AKR LOW VOLTAGE POWER CIRCUIT BREAKERS ssT SOLID STATE OVE...

Page 31: ...c w w w E l e c t r i c a l P a r t M a n u a l s c o m ...

Page 32: ...7 78 GENERAL ELECTRIC COMPANY CIRCUIT PROTECTIVE DEVICES DEPARTMENT PLAINVILLE CONNECTICUT 0606 2 G E N E R A L E L E C T R I C 0 J w w w E l e c t r i c a l P a r t M a n u a l s c o m ...

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