Page 1: ...EAKERS AK 2 3 2A 3A 50 50S AK 2 3 2A 3A 75 75S AK 2 3 2A 3A 1QO 100S TYPES AKT 2 3 50 SOS_ AKU 2 3 2A 3A 50 SOS AKF 2C 2D 2E GENERAL f j ELECTRIC GEK 7303B Supersedes GEH l 798A GEI 50211 GEH 1799 GEI...
Page 2: ...ACTING TRIPPING DEVICE EC lB SERIES OVERCURRENT TRIPPING DEVICE Ec 1 SERIES OVERCURRENT TRIPPING DEVICE EC 2 EC 2A REVERSE CURRENT TRIPPING DEVICE AIC 50 ONLY POWER SENSOR TRIP e SELECTIVE TRIPPING B...
Page 3: ...AK 2 75C The C indicates the interrupting rating has been increased to the rno ooo amp class AKT 2 50 The T indicates incr ased continuous rating of 2000 amps AK 3 50 AK 3 75 AK 3 100 The 3 indicates...
Page 4: ...the closing springs At the endofthe charg ing oper tion w chtakes approximately5seconds a latch plate engages the prop roller to prevent _the closing springs from discharging With the closing springs...
Page 5: ...ng force To il stall the safety pin of the man al stored energy mechanism refer to the section entitled STORED ENERGY MANUAL MECHANISM on page 17 of these instrucUons With the safety pin restraining t...
Page 6: ...out Faulty control circuit component Improper contact sequence main contacts not sufficienUy parted when arcing contacts part Short circuit current leJel above inter rupting r ating of breaker Loss of...
Page 7: ...e reaker from the outside pole units 3 Remove the clevispin 14 Fig 6 13 Fig 7 from the center pole unit 4 Remove the six nuts from the back frame using a socket wrench with an extension These include...
Page 8: ...quencher as indicated in Fig 5 6 Muffler 7 Compound Support 8 Steel Back Plate 9 Spacer Block 3 Remove bolt fastening cap 4 and barrier plate assembly 4 Barrier plates may now be lifted from as sembly...
Page 9: ...sulated link 12 to tl e breaker mechanism In addition to ste e1 springs shunting the current from the contact directly to the lower contact block steer springs 17 force liiie con cts ag nst the pins t...
Page 10: ...er contact wipe andpressure on the center pole dimension A should be increased to increase wipe and decreased to decrease wipe 2 To ch ange dimension A removethe clevis pin 14 and rotate the clevis as...
Page 11: ...the m tenance h dle ith _ the safetypin rel trammg th_e closingsprings If the gap is under the required minimum it is usually possible to form the arcing contacts and obtain the re_quired dimensions...
Page 12: ...unit assembly AK 75 and AK 100 The movable arcing contacts 4 should be replaced when the stationary arcing contacts are replaced 1 Separate the front frame from the back frame as describedunderSEPARA...
Page 13: ...urefollow Low Voltage Power Circuit Breakers GEK 7303 Fig 9 8039669 Front view of back frame assembly AK 3 50 1 Power Sensor Coil Assembly 2 Disconnect Plug 3 Tr msformer Taps in Amper s ing contact r...
Page 14: ...IC tJE CHANSM N a osED POSITl I CLOONG SPRf lG ClSOtARGED 1 Spring z Cam 3 Link 4 Reset Spring 4A Spring Adjusting Nuts 5 Prop 6 Adjus ting Screw 7 Adjusting Screw Stop Pin 8 Prop Return Spring 9 Roll...
Page 15: ...d Adjustments Fig 11 All adjustments should be made with the opera ting mechanism in the reset position as shown in Low Voltage Power Circuit Breakers GEK 7303 1 Fig 13 8018984 Rear view of front fram...
Page 16: ...rrested by pi ap and latch arrangement The subsequent closing operation is accomplished by tripping the latch to release the prop which in turn allows the springs to continue the interrupted dischargi...
Page 17: ...120 degrees When approximately 70 degrees of the fourth clockwise stroke have been completed the closing springs which have been charged during the previous strokes ot the closing handle are driven o...
Page 18: ...n and Chain 13 Shims 23 Closing Handle Shaft and Pawl Asm 4 Safety Pin Hole 14 Groove Pin 24 Roll Pin 5 Closing Springs 15 Nylok Screw 25 Main Closing Crank 6 Guide Rod 16 Ratchet Wheel Shaft and Asm...
Page 19: ...16 lb 3 Ga_p between contacts when center pole is open 1 1 2 in to 1 3 4 in 4 Overlap between the center pole contacts and the arcing contacts of the outer poles 3 16 in to 7 16 in _ Measurements of...
Page 20: ...from the factory 2 It may be necessary to add buffer stop shims 27 to the buffer stop 26 to provide a clearance of 1 64 to 1 32 inch between the pawls 21 and the buffer stop when the pawls are touchin...
Page 21: ...uld be remove d If it is to be decreased they should be added Shims may be removed by sliding them to the front of the breaker They are slotted for easy r_ emoval Effect of this ad j1 1stmen on contac...
Page 22: ...gular link 6 set across the a terminals ofthe auxiliary switch 4 Set arrow on new auxiliary switch shaft 5 Push auxiliary switch shaft 8 into square hole in link breaker open _ 6 Replace mounting hard...
Page 23: ...the escutcheon A hole is provided in the escutcheon to allow operationof the switch Remove the escutcheon to gain access to the switch CUT OfF SWITCHES Fig 21 The motor cut off switches are mounted on...
Page 24: ...to be moni tored is connected to Terminals 1 and 2 of the the time delay box The undervoltage device on the breaker is always connected through either its secondary disconnects or terminal board to t...
Page 25: ...9 1830 Ohms 2 6275081 G 61 440 Ohms REPLACEMENT 1 Disconnect coil leads 2 Remove four mounting screws 21 and remove device 3 Install new device in reverse order Coil ls 1 Disconnect leads to coil 2 Re...
Page 26: ...instan aneous tripping is adjustable Irqm bO percent to 250 percent of the continuous current rating of the device Whenever this is used it is the only characteristic of the device Instantaneous trip...
Page 27: ...ove stud 23 4 Remove two screws fastening magnet 11 to lower stud 5 Device is now free of breaker Reassembly is accomplished by reversing the procedure When reassembling the magnet to the lower stud b...
Page 28: ...een the connecting rod and the insulated coupling which ties onto the trip paddle 14 The approxi mate distance between the pivot centers on the ends of the connecting rod assembly is six inches The co...
Page 29: ...alib ratio spring 11 After the magnetic force produced by an overcurrent condition overco es this restraining force the armature movement is further retarded by the flow of silicone oil in a dashpot w...
Page 30: ...travel at least 5 32 in 5 Replace new devi9e in rever se order 6 Adjust device as described above NOTE Component parts of any overcurrent tripping devices are not replaceable It will be necessary to i...
Page 31: ...pped with this setting at the 2 3 mark and the 1C characteristic at the 1 3 mark The stand ard characteristic curves are plottedatthese same settings Time values are inversely proportional to the effe...
Page 32: ...The trip screw 6 on the end of the armature 7 should be set so that it does not contact the trip paddle on the trip shaft until the air gap between armature and pole piece is reduced t 3 32 in or less...
Page 33: ...usting nut upward one and one half turns 4 Tighten the locking nut and the mfnimum 1 32 in overtravel of the trip rod should be obtained Low Voltage Power Circuit Breakers GEK 7303 REPLACEMENT Fig 31...
Page 34: ...trouble shooting 3 A PST 1 Power Sensor Test Kit must be available rig 39 Check the Power Sensor Unit for correct function f r each pick up setting and one point on each time d lay characteristic Then...
Page 35: ...rmance o t1 e Power Sensor Unit and the Power SUpply Unit it may be advisable or required to test the magnetic coils by the use of a Hi current Low voltage type test set In this event on1y one test pe...
Page 36: ...ws 5 Remove Power Supply Unit with control wiring 6 Reassemble in reverse order SENSOR Coils AK 3 50 Only_ Fig 32 1 Disconnect J_ lug between the Power Supply Unit and the sensor coils and rempve tapp...
Page 37: ...citor 4 Female Disconnect Plug 5 Male Disconnect Plug 6 Mounting Brackets 6 2 __ Fig 35 8039649 Power Sensor Unit 1 Mounting Screw 2 Captive Thumb Screw 3 Name Plate Fig 36 8039903 Magnet Trip Device...
Page 38: ...J 0 Q J u II I J 5ouRCE tu I 0 I w 2 w u w J A 0 z cf r r 5 c i t a ROl NO SENSOt I C 011 2I I u 1n 1oillT CMLI 47 11 1 0lMO t a E I rn P1 ID Po cl S1 PL 1t PQ1 4 A isoA C 01L I 1 r i1 I I 1 fa 1 I la...
Page 39: ...upported cyl inder now move to center pole d O t side Pole until coils are removed place coils with resistor board on clean flat surface When removing coils from your arm be careful not to break orf u...
Page 40: ...l 1 1 l l 1 l 44 HH V I A I I I I 1 a l 1 l N r l Ii 11 I I LI I I I I I 1J 1 J JJI I J j i 2 i 2 SX T 1 r 2 Sll _ 1ox u IOX r A A X X 1 1 a J I I Ml11 I I JI Ill I I A I I I I llt 1 a r1 n A1C 1S AK...
Page 41: ...r r rr rr r r r I 1 r J I 0 30 Soc J 1 l I r I Ii o 24Sec r l r I o tts l t0 r i 0 12 Soc I 1 0 06 Sec 1 I I I 1 I IUIII I IJ JI t I I I I 1 I I I l l I I I a I r I I 1 r I I ttl I 11 1 I I 1 I I C E...
Page 42: ...on from being performed wlien the breaker is closed Ins erting the breaker into the housing causes the racking pins on the housing to engage the semi circular slot in the racking c m 4 In this positio...
Page 43: ...e carefully noted and the number of turns of the nuts shoula be counted so that in reassembly the original amount of compression can be restor d by replacing the nuts to their fo rmer position on the...
Page 44: ...EWS 6 MAGNET 7 COIL 8 CLAMP 9 ARMATURE 10 ARMATURE ARM 1 II TRIP PADDLE 12 CLAMP Shunt tripping device 3 Bend lower end of clamp 8 straight and remove 4 Remove coil anq install new coil in re verse or...
Page 45: ...ook around the shunt trip armature lever 8 in a manner that will assure the device latch and catch are disengaged before the breaker opens OPEN FUSE LOCKOUT DE VICE Fig 47 The open fuse lockout device...
Page 46: ...5 t 6 7 8 J 14 guide 2 Continue lowering the device until movement is restricted by the device wiring harness 2 Disconnect leads to coil 6 3 Remove two screws holding the trip device to the device mo...
Page 47: ...K 7303 Allen Wrenches 1 16 in for No 6 screw 5 64 in for No 8 screw 3 32 in for No 10 screw 1 8 in for 1 4 in screw 5 16 in for 3 8 in screw with adapter shank for 1 2 in drive ratchet 3 8 in for 1 2...
