SECTION 1-lntroduction A basic inspection should consist of the following: a. Visual Check - Look for dirt, grease or other forei These instructions provide the maintenance procedures material on any breaker parts. Check insulating surfac and describe the operation of the thru 2000 amp frame...
SECTION 2-General Description Type AKR low-voltage power circuit breakers are used for controlling and protecting power circuits in the low voltage range (usually up to 600 volts). In serving this function, they are a means of safely switching loads and automatically clearing circuits when abnormal conditions occur.
SECTION 2-General Description {Cont.) TRIP DEVICE MOUNTING There are types of solid-state, direct-acting, self Type AKA breakers are designed for either drawout or powered trip device systems associated with AKA break stationary mounting. Drawout breakers (See Fig. ers. These systems are for AC applications only. For DC equipped with features which make them easy to install in applications an electro-mechanical system is available.
SHORT CIRCUIT RATINGS Short circuit ratings vary with the applied system vol VAC systems they are also dependent upon tage. On whether the overcurrent trip device contains an instan taneous trip element. See Table TABLE 4 - BREAKER INTERRUPTION RATINGS 3c/>...
SECTION 3-Storage The rejection hardware prevents the converse bf a. thru d. above. A detailed description of the rejection pin and bracket combinations used is given in Installation manual, GEl It is recommended that the breaker be put into service 86150.
ELECTRICAL CLOSING SECTION 5-Breaker Operation On electrically operated breakers the closing springs are charged by a gear motor. With the springs discharged, voltage applied to the control circuit will energize the motor " " through the switch contacts - see Fig. The motor, A breaker may equipped to operate either manually...
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5.2.1 ALTERNATE CONTROL CIRCUIT breaker (if so equipped) or by a remote closing switch. Later production breakers use the electrical control Operation of the closing switch energizes the K-relay circuit shown in Fig. 9A for all control voltages except which in turn energizes the closing solenoid. Thi�...
5. 3 M ECAHNISM OPERATION Figure 10 shows the mechanism components in the Closed, Tripped and Reset positions. The closing spring is shown in the charged position in all of these details. Closed Position- As shown in Fig.10A, the movable contacts are held against the stationary contacts by the toggle linkage.
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SECTION 5-Breaker Operation {Cont.} (�i:) El £ G f N ERA L FIG. 1 2 ROLLER ENGAGED WITH CLOSING PROP There is a ratchet assembly attached to the camshaft Rotate the camshaft using the maintenance handle until the ratchet assembly's roller engages with the prop. Do not extension.
SECTION 6-lnterlocks breakers are equipped with safety interlock devices that are required by Industry Standards and Certifying Au thorities. Interlock devices for special applications are also available as options. The standard interlock devices de scribed below are used only on drawout breakers. Station ary breakers have no required interlocks.
SECTION 6-lnterlocks (Cont.) FIG. 1 5 FIG. 1 6 - POSITIVE INTERLOCK RACKING SCREW COVER INTERLOCK C LOSED POSITION position, the crank's pin reaches the end of the slot in the linkage. Continued motion of the racking mechanism causes the linkage to rotate the lever which moves the closing solenoid armature forward.
DISCONNECT POSITION I NTERLOCK The function of the Disconnect Position Interlock is to block the RACKING SCREW cover open when the racking mechanism is in the DISCONNECTED position. When the cover is held open, the TRIP button is depressed. The mechanism is held trip-free and there is no contact arm movement when the closing spring is discharged by the Closing Spring interlock.
SECTION &-Interlocks (Cont.) O PTIONAL INT ERLOCKS KEY I NT ERLOCK-STAT IONARY B REAKER The optional interlocks are key interlocks and door inter The function of the Key Interlock is to prevent an open locks. On drawout breakers, these devices are mounted in breaker from being closed when the lock bolt is extended the equipment and are part of the breaker enclosure.
SECTION 7 -Breaker Maintenance (Cont.) MANUAL HANDLE ADJUSTMENT The areas requiring l ubrication are: On manually-operated AKA breakers, the closing springs may be charged either by a single 1 35 degree Contacts - A thin fil m on the stationary and clockwise handle stroke or up to four multiple strokes of movable contact assembly pivot surfaces.
SECTION 7-Breaker Maintenance (Cont.) D RAWOUT MECHANISM POSIT ION Remove the hex-head bolt only, do not remove or loosen the slotted head screw shown in Fig. 21 . Removal of the Maintenance or inspection should be conducted with the slotted head will cause the closing spring to become dis breaker on a workbench.
SECTION 7-Breaker Maintenance (Cont.) P RIMARY DISCONNECTS ampere breakers use four primary disconnect Primary disconnects are found only on drawout break fingers per phase. The 1 600 and 2000 ampere breakers use eight fingers per phase. Fig. 22 shows a line and load ers.
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SECTION 7-Breaker Maintenance (Cont.) 7 .5.1 REPLACEMENT Figs. 22, 23, 24, and 25 show the primary disconnect assembly breakdown. Refer to these illustrations when replacing the disconnects. Note the following details: Fig. 25- The position of the spacer in the breaker stud. The hole in the spacer must be positioned as shown so it will align with the holes in the clip.
:To check the setting, arrange the breaker for "slow 7.4. close" as described in Section Through the use of a continuity tester, observe the position of the breaker con tacts when the switch's LI-LIC "A" contacts touch. At this � point the breaker's arcing contacts must be within .250 "•...
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SECTION 7-Breaker Maintenance (Cont.) FIG. 32A - UNDERVOLTAGE DEVICE If excessive clearance or binding exists, loosen the screws holding the magnet assembly to the frame and move the magnet up or down as necessary. Tighten the screws to 27 to in-lbs.
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When adjusting the pick up level on instantaneous de undervoltage devices, set the gap between the armature INSERT .030 WIRE and magnet to inches using the adjustment screw GAGE shown in Fig. 32C. After setting the pick up level, use this same adjustment screw to obtain the drop out setting.
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SECTION 7-Breaker Maintenance (Cont.) Check resistance of the disconnected undervoltage device. for values. instruction Sheet GEH-4545 for more detailed infor mation, including schematic diagrams and circuit descrip tion. The undervoltage device must be calibrated through the time-delay unit after the device pick up has bee n adjusted. .008 inch minimum closed g must exist between the ar...
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SECTION 7-Breaker Maintenance (Cont.) 7.1 1 .3 REPLACEMENT The mechanism i s reset by disengaging the side latch link from the upper latch link or by closing the breaker if a bell alarm Is mounted on the right hand side of the frame locklever is not provided.
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SECTION 7-Breaker Maintenance (Cont.) 7.12.1 COMPONENT REPLACEMENT To gain access to the electrical control components, the breaker's front escutcheon must be removed. Type B breakers require that both the deep molded escut cheon and the shallow steel escutcheon be removed. Before removing the front escutcheon on Type A or B breakers, a supporting block should be placed under the 36A,...
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F AND G SWITCH ADJUSTMENT 7 .1 2.2 For proper electrical operation, the F and G mechani cally operated switches must operate at the proper point in the closing c ycle. If these switches are to be replaced, measure the distance between the tip of the switch button and the bracket on which they are mounted.
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SECTION 7-Breaker Maintenance (Cont.) FIG. 38 - D RAWOUT MECHANISM DETAI LS FIG. RACKING MECHANISM INSTAL LED...
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SECTION 7-Breaker Maintenance (Cont.) 7.1 4 B UFFER ASSEMBLY When the breaker is closed, the energy in the closing When the break�r is opened, the end plate assembly is spring is transferred to the main s haft through the driven against the opposite end of the buffer assembly. mechanism.
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SECTION 7-Breaker Maintenance (Cont.) NEOPRENE WASHERS 7.1 4.1 BUFFER ADJUSTMENT Referring to Fig. 40, with the breaker closed and the mechanism not reset, a .005 " min. clearance must exist between the end plate assembly and the buffer nut as shown.
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SECTION 8-Contact Maintenance ARC CHUTE REMOVAL AND INSPECTION Breakers subjected to frequent interruption of high cur There are two types of arc chute construction used on rents may eventually require replacement of their contacts. 2000 thru ampere breakers. They are the ceramic The general rule for determining need of replacement is type shown in Fig.
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SECTION 8-Contact Maintenance (Cont.) CONTACT ADJUSTMENT AKR 30130H & AKRU 30 The contact structure of the AKR 30 and the AKRU 30 breakers is slightly different from the AKR 30H. Referring to & B, Fig. both structures use one moveable contact arm, and two stationary arcing contacts.
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SECTION 8-Contact Maintenance (Cont.) A K R 30H FIG . 448 800 AMP CONTACT STR U CT U R ES...
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SECTION 8-Contact Maintenance {Cont.) CONTACT ADJUSTMENT - AKR 50150H & AKRU 50 · Attach a continuity checker (bell-set, light, or ohm The contact structure shown in Fig. 47 is used by all AKR50 breaker types. This structure uses two movable meter) between the upper and lower stud.
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CONTACT ADJUSTMENT AKRT 50/SOH 1 . Open the breaker. The contact structure shown in Fig. 48 is used by all AKRT 50 breaker types. This structure is similar to the AKR Arrange the breaker for slow-closing. 50 structure. There are two movable contact arms, each 3.
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SECTION 8-Contact Maintenance (Cont.) STATIONARY CONTACT IDENTIFICATION The stationary arcing, intermediate, and main contacts each have a different function during current conduction and current interruption. For this reason, these contacts are made using different material compositions. Also, the different functions require that the contacts replaced in configurations shown in Figs.
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CONTACT REPLACEMENT - CONTACT REPLACEMENT AKR 50/50H , AKRU 50 & AKRT 50/50H AKR 30/30H & AKRU 30 Refer to Stationary Contact Identification, Section 8.5, Refer to Stationary Contact Identification, Section before replacing any stationary contacts. before replacing any stationary contacts. The stationary intermediate and main contacts are The stationary contacts are held in place by the contact replaced just like the stationary contacts on the...
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SECTION 8-Contact Maintenance (Cont.) FIG. ARC RU N N ER REMOVED FIG. SOC - ARCING CONTACT SOB - PIVOT REMOVED...
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SECTION 9-Fused Breakers SPECIAL 2500A FUSE FOR AKRU-50 There are two types of fused breakers; AKRU 30, 800 ampere frame and AKRU 50, 1 600 ampere frame. Except This fuse provides a melting time-current characteristic for the open fuse lockout device and the integrally that coordinates with 1 600A trip devices.
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SECTION 9-Fused Breakers (Cont.) WHEN REPLACING THE FUSE IN THE CAUTION: LEFT POLE (FRONT VIEW) OF THE BREAKER, NOTE PAR TI C ULARL Y THA T THIS FUSE IS MOUNTED DIFFERENTLY THAN THE OTHER TWO FUSES. A S SHOWN IN FIG . FOR THIS PHASE 1 80 THE FUSE IS ROTA TED...
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SECTION 9-Fused Breakers (Cont. ) OPEN FUSE LOCKOUT DEVICE This device automatically trips the fuse breaker if one of the fuses opens. When this happens, the breaker is locked open until the reset button of the phase involved is pushed. The breaker should not be reclosed, of course, until the opened fuse is replaced.
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SECTION 9-Fused Breakers (Cont.) -·- ==r ___) _. ARMATURE RESET BUTION FIG. 56A-DETAILS FIG. 568-INSTALLED TYP E A OR 8 B R EAKER O FLO DEVICE...
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SECTION Type SST Overcurrent Trip Device • The SST is a solid-state, direct-acting, self-powered trip device system. The SST system consists of the SST pro grammer unit, current sensors, and a flux shifter trip de OVOI.CWI vice. Fig. 57 shows a block diagram of the system. I TAIIGET 1 0.1 PROGRAMMER UNIT...
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SECTION Type SST Overcurrent Trip Device (Cont.) FIG. 59 - AKR-58-30 1 0.2 C U R RENT SENSORS · The SST system uses two types of current sensors, phase sensor and a neutral sensor. Fig. 60 shows a phast. sensor. Fig. 61 shows the neutral sensors available. The current sensor supplies the power and sig nal inputs necessary to operate the trip system .
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1 0.2.1 REPLACEM ENT O F CU R RENT SENSORS d) When rep laci n g the stud connector, tighten the Referri ng t o F i g . 63, replacement o f i nd ividual SST ± Allen head screws to 250 10 i n·l bs.
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So long as the actuator remains i n the Reset posi 1 . Remove the flux shifter leads from the harness. tion the breaker can be closed and opened normally 2. Referri ng to the cabl ing d i ag rams in Section 1 0.5, at will.
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1 0.4 TROU BLESHOOTING When malfunctioning is suspected the first step in b) using the Ground Fault Defeat Cable as shown troubleshooti ng is to examine the circuit breaker and its in Fig. This special test cable energizes a ll the power system for abnormal conditions such as: primary windings of the differential transformer in a self-cancelling, series-parallel connection so...
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SECTION Type SST Overcurrent Trip Device (Cont.) SST TEST SET 1 0.4.1 1 0.4.2 RESISTANCE VALUES The TAK-TS1 and TAK-TS2 Test Sets are portable in struments designed for field-checking the time-current For use in troubleshooting, the Common to Tap resist characteristics and pickup calibration of the SST's ance for SST current sensors is given in Table 8.
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SECTION 1 0-Type SST Overcurrent Trip Device PROGRAMMER DEVICE FLUX SHIFT ,-- - -- - UNIT TRIP WHITE BLACK WHITE BLACK WHITE LOAD PROGRAMMER CONNECTOR 201217·1) (AMP FIG. 69 - CABLING DIAGRAM - SST WITH GROUND FAULT ON 3-WIRE LOAD PROGRAMMER DEVICE FLUX SHIFT...
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SECTION 1 1 -Type ECS Overcurrent Trip Device The ECS is a solid-state, direct-acting, self-powered trip device system. The ECS system consists of the ECS programmer unit shown in Fig. 72, current sensors, and a fl ux shifter trip device. Fig. 73 shows a block diagram of the system.
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TABLE 9 ECS TRIP CHARACTERISTICS ECS PROGRAMME R ADJUSTMENT RANGE (Set Points) Trip • Rating in Amperes Short Time -- - � • SeDSOr Rating Long Time Frame Size Instantaneous ® ® Breaker Band ® Type Pick (•L) Time Pickup Time Picku p Sensor...
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SECTION 1 2-MicroVersaTrip™ Trip Device 1 2.1 .1 FAULT TRIP INDICATORS The MicroVersaTrip is a solid-state, direct-acting, self-powered trip device system. The MicroVersaTrip The optional fault trip indicators are similar to the SST system consists of the MicroVersaTrip programmer, indicators. They are mechanical pop-out type for identify current sensors, and a flux shifter trip device.
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The remote fault Indication switch leads are brought out the bottom of the Mi.croVersaTrlp programmer as shown In Fig. 78. This switch lead harness is plugged Into the mating connector on the breaker, see Fig. 79. The switch leads are brought out from the breaker through the Programmer Secondary Disconnect shown In Fig.
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TABLE 1 1 TRIP FUNCTIONS AVAILABLE Features BASIC FUNCTIONS ADD TO BASIC FUNCTIONS STD.-or-5-or-H-or-M G-or-GR A 1-or-A2-or·A:kK·A Z1 -or-22-or-Z • Adjustable Current Setti ng • Adj Long-Time Pickup • Adj Long- Time Delay LONG • TlME • Remote Long-Time Timing Ught Short - •...
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SECTION 1 2-MicroVersaTrip™ Trip Device (Cont.) TAPPED COMMON TERMINAL FIG. M I C ROVERSATRIP'M PHASE 83 - FIG. TYPICAL N EUTRAL S ENSOR SEN SORS "'••"'t �� '- .& • •-.G C t �a.. E :: ' � � { ' H '-Optlon Phase Sensor FIG.
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Since the neutral sensor is mounted separately from the breaker, a d i sconnect means is requi red to con nect its output to the breaker. Fig. 86 shows the breaker and equi pment mounted 4th wire secondary d i sconnect used with the M icroVersaTrip system. 1 2.2.1 REPLACEM ENT OF CU RRENT SENSO RS...
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SECTION 1 2-MicroVersaTrip™ Trip Device (Cont.) 1 2.3 FLUX SHIFTER TRIP DEVICE Once It has been established that the circuit breakf can be opened and closed normally from the test posltior., The only difference between the MicroVersaTrip and attention can be directed to the trip device proper. Testing SST flux shifter trip devices is the solenoid winding.
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SECTION 1 2-Micro Versa Trip ™ Trip Device (Cont.) 1 2.5 CABLI N G DIAG RAMS •B • c •A PROGRAMMER A A A FLUX SHIFT UNIT TRIP DEVICE rf -1-t- \ �-- - -- - ..? � ��� � )===)= ..
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• a • c PROGRAMMER SHIFT FLUX r- - --- UNIT TRIP DEVICE BREAKER BACK FRAME � NEUTRAL SENSOR - - 1 DISCONNECT LINE HARNESS PR O GR AMMER CO N NE CT O R CO N NE CTOR AM P 1 _350 356- 9 FIG.
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PROGRAMMER REMOTE FAULT MICRO-VERSA TRIP SECONDARY INDICATION PROGRAMMER CONNECTOR DISCONNECT EQUIPMENT BREAKER , - - - - -1 OVERLOAD SHORT CIRCUIT GREEN GROUND FAULT OVERLOAD PICKUP ...J _ _ _ 1·350239-9 1-350242·9 1·350235-9 1-350246-9 FIG. 95. CABLI N G DIAGRAM-REMOTE FAULT I NDICATION PROGRAMMER MICRQ-VERSA TRIP SECONDARY...
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SECTION 1 3-EC Trip Device Type EC overcurrent trip devices are magnetically The standard EC trip device for breaker frames up operated, using a series coil or single conductor, and an amps is the type EC-2A, see Fig. 97. An optional tr., 2000 associated magnetic structure to provide tripping force.
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1 3.1 .2 INSTANTANEOUS LOW-SET TRIPPING 13.1 SERIES OVERCURRENT TRIPPING DEVICE EC-2A The low-set instantaneous pick-up point may be varied by the adjustment knob The calibration in this case usually ranr (3). The Type EC-2A overcurrent tripping device is available in from 80 percent to 250 percent of the series coil rating, with .
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comes this restraining force, the armature movement is further 1 3.2 SERIES OVERCURRENT TRIPPING retarded by an escapement mechanism which produces an in DEVICE Ec-1 verse time delay characteristic. The mechanism is shown on Each series overcurrent tripping is enclosed in a device Fig.
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1 3.3 POSITIVE TRIP ADJUSTMENT 1 3.2.3 INSTANTANEOUS TRIPPING Before attempting any checks or adjustments on breaker wi� (a) Adjustable instantaneous tripping takes place after the EC trip devices, the breaker mechanism and trip latch should magnetic force produced by an overcurrent condition, over comes the restraining force of the calibration spring which checked to assure their proper functioning so that the breakt.
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SECTION 1 3-EC Trip Device {Cont.) normal direction, the magnetic flux of the series coil and the 1 3.4 REVERSE CURRENT TRIPPING DEVICE magnetic flux of the potential coil produce a torque which tends case The device is enclosed in a molded and is mounted on to rotate the armature counterclockwise.
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1 3.6 13.4.1 TRIP DEVICE REPLACEMENT ADJUSTMENTS Overcurrent devices on AKR30 & AKR50 breakers may bA The only adjustment to be made on the reverse current de · dismounted by removing fastening hardware at the rear vice is to make sure that the trip has a minimum overtravel beia of 1 /32 in.
·sECTION 14-Eiectrical Characteristics TABLE 1 6 CHARGING AND CLOSING OPERATING CURRENTS MOTOR ANTI·PUMP CONTROL CLOSING RELAY "W" RELAY "X" "' SOLENOID Current (Amps) "" � • • • o a. "S a. "S a. Cll . t:: CII � 0 Rated-Amps Rated Amps Rated Amps...
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TABLE SHUNT TRIP AND UNDERVOL TAGE DEVICE OPERATING CURRENTS SHUNT TRIP UNDER VOLTAGE "" 8 & Current Current (Amps) (Amps) 'i .! I > Operating lnruah Operlltl n g lnruah Sealed Sealed "" Voltage ,.nge Open Open Cloud CloMd Voltage ,.nge .
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TABLE 23 1NSTANTANEOUS UNDERVOLTAGE DEVICE SETT I NGS PICK UP VOLTAGE RANGE COI L UVR I N STALLED DROP OUT UVR O N LY MECHANISM R ESET RATING RANGE 24 VDC 1 8 . 20 1 6 . 20 7 . 8.3 48 VDC 36 .
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These ,nst'vtflOI"' Oc "'01 D""'P<Y' IU co..,- all o.t.,s 01 .,.,..flrOtt J , eoutpmerlf f"'()t ro oro .. •att ,.._ .., ()( l ' ' �. ( �� .. rc o. ,.,., ,., CO"W"'eC&ot" .,., '"S'Mf•ttor" For further 1nformat1on General Electnc call Gpitl•t•OI"' Of ..,.,,.,.,�...
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GEK-644590 Maintenance Manual Low Voltage Power Circuit Breakers Types AKR-30 I 50 AKRT-50...
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Low Voltage Power Circuit Brea kers Table of Contents Page Page SECTIO N 1 SECTIO N 7 1 .0 I NTRODUCTION Auxil iary Switch 7.6. 1 1 . 1 I nspection and M ai ntenance Replacement 7.6.2 Adj ustment 1 .2 Renewal Parts Shunt Trip SECTIO N 2...
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Page Page SECTION 1 0 SECTION 1 4 1 0.0 TYPE SST OVERCURRENT 1 4. 0 M ICROVERSATRI P '" P LUS AND M ICROVERSATRIP PM TRIP U N ITS 7 7 TRIP DEVICE 1 4. 1 Trip U n it 1 0.1 Programmer Unit 1 4.
SECTION 1 -lntroduction A basic i nspection should consist of the following : a. Visual Check - Look for dirt, grease or other foreign These i nstructions provide the mai ntenance procedures material on any breaker parts. Check insulati ng surfaces and describe the operation of the thru amp frame...
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TABLE 1 BREAKER MODELS MOUNTING TYPE DRAWOUT FRAME SIZE BREAKER S U B- DEEP FUSED (AMPERES) DESIGNATION AKD-5 AKD-8 STRUCTURE STATIONARY ESCUTCHEON BREAKER AKR-(*)A 30, 30H AKR-(*)8 30, 30H AKR-(*) D 30, 30 H , 30L AKR-(*)S 30, 30H AKR-(*)A 50, 50H AKR-(*)8 50, 50H 1 600 AKR-(*)D 50, 50H...
The d rawing number appears on the breaker nameplate and can be obtained from GE. FUSED/NON FUSED 2 . 1 FRAME S IZ E Fused breakers are identified as either AKAU 30 (800 ampere frame size) or AKAU 50 ( 1 600 am pere frame size) .
SECTION 2-General Description (Cont.) TRIP DEVICE 2 .4 MOUNTI NG Type AKA breakers are designed for either drawout or There are several types of solid-state, direct-acti n g , self stationary mounting. Drawout breakers (See Fig. powered trip d evice system s associated with AKA equi pped with features which make them easy to instal l in breakers.
SHORT CIRCUIT RATINGS 2 .7 Short circuit ratings vary with the applied system vol tage. On 240 VAC systems they are also dependent upon whether the overcurrent trip device contains an instan taneous trip element. See Table 4. TABLE 4 BREAKER I NTERRUPTION R ATINGS 3<!>...
3 . 1 Safety SECTIO N 3 . 0-Storage, Safety, Maintenance Each user must maintain a safety program for the protec tion of personnel, as wel l as other equipment, from the I t is recommended that the breaker be put into service potential hazards associated with electrical equ ipment.
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3 . 2 Maintenance Instruction books supplied by manufacturers address Both long and short term maintenance o f a l l electrical com ponents that would normally require service or main equipment is essential for rel iability and safety. Mainte tenance during the useful life of the equi pment.
ALTERNATE CONTROL CIRCUIT USED 5.2.1 equipped) or by a remote closing switch. Operation of the A second type of electrical control is shown in Fig . 9A closing switch energizes the K-relay, which in turn ener for all control voltages except 250 volts D.C. which uses g izes the closing solenoid "CC".
M ECHA'N ISM O PE RATIO N Figures 1 OA, 1 08 and 1 O C show the mechaniSm com .. ponents in the Closed, Trip ped and Reset positions. The closing spring is in the charged position for all of these details.
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SECTION 5-Breaker Operation (Cont.) FIG . 1 2 - R O L L E R ENGAG E D WITH CLOSING PROP T h e r e i s a ratchet asse m b ly attached t o t h e c a m s h aft Rotate the camshaft u s i n g the m ai ntena nce h a n d l e u n t i l exte n s i o n .
SECTION 6-lnterlocks AKR breakers are equipped with safety interlock devices that are requi red by I ndustry Standards and Certifyi ng Au thorities. I nterlock devices for special applications are also available as options. The standard interlock devices de scribed below are used only on drawout breakers. Station ary breakers h ave no required interlocks.
SECTION 6-lnterlocks (Cont. ) INTERLOCK FIG. 1 5 FIG. 1 6 - POSITIVE INTERLOCK RACKING SCREW COVER I NTER LOCK CLOSED POSITION crank pin reaches the end of the slot in the linkage. Continued motion of the racking mechanism causes the linkage to rotate the lever which m oves the c losing sole...
DISCONNECT POSITION I NTER LOCK The function of the Discon nect Position I nterlock i s to block the RAC KING SCREW cover open when the racking mechanism is in the D I SCONN ECTED position. When the cover is held open, the T R I P button is depressed . The mechanism is held trip-free and there is no contact arm movement when the closing spring is discharged by the Closing Spring i nterlock.
SECTION 6- lnterlocks (Cont.) KEY I NTERLOCK-STATIONARY When the breaker is in the C LOSED position , the fly B R EAKER wheel assembly item #2 is away from the lever item #6. The lever is spring loaded and rotates clockwise causing its pin to block the lock bolt extension.
SECTION 7-Breaker Maintenance (Cont.} MANUAL HANDLE ADJUSTMENT The areas req u i ri ng l u brication are: The adjustment l i n kage co nnects the handle assembly to Contacts Pivots - A t h i n fi l m on t he stat ionary the chain drive mechanism which turns the cam shaft.
SECTION 7-Breaker Maintenance ( Cont.) D RAWOUT MECHANISM POSITION Remove the hex-head bolt only, do not remove or loosen Maintenance or inspection should be cond ucted with the the slotted head screw shown in Fig . 2 1 . Removal of the breaker on a workbench.
SECTION 7 -Breaker Maintenance {Cont.) The 800 ampere b reake rs w it h the exception of P R IMARY DISCONNECTS 30L use four primary d isconnect fingers per term inal. Primary disconnects are found only on drawout break The 1 600 amp, 2000 amp and 30L b reakers use ers.
E LECTROSWITCH TYP E 1 01 Adjustment is the same as the GE S B 1 2 except that when the switch "A" contacts touch, the breaker arcing contacts m ust be w ithin 0 to .250 inches of c losing.
SECTION 7 -Breaker Maintenance (Cont.) D ROPOUT VOLTAGE: On AC devices the d ropout level will fall within the req u i red limits (30% to 60% of the coil rating) if the pickup is set properly. On DC d evices, the d ropout level may need independent adjustment.
INSERT WIR E OPEN GAP G A GE ADJUSTM ENT FIG. 328 - OPEN GAP CHECK FIG. 320 POSITIVE TRIP CHECK When installed, the voltage to be monitored is connected across term inals No. 1 and No. 2 of the static delay box.
SECTION 7 -Breaker Maintenance (Cont.) 3. Check resis t ance of the disconnected undervoltage device. See Table 5 for values. See i nstruction Sheet G EH-4545 for more detai led infor mation, i ncluding schematic diagrams and circuit descrip tion. The undervoltage device must be calibrated through the time-delay unit after the device pick up has been adjusted.
SECTION 7-Breaker Maintenance ( Cont.) 7.1 1 .3 REPLACEMENT The mechanism i s reset by disengaging the side latch link from the upper latch link or by closing the breaker if a The bel l alarm is mounted on the right hand side of the locklever is not provided.
SECTION 7-Breaker Maintenance (Cont.) 7.1 2.1 COM PONENT REPLACEMENT To gai n access to the electrical control com ponents, the breaker's front escutcheon m ust be removed. Type B and D breakers requ i re that both the deep molded escut cheon and the shal low steel escutcheon be removed.
7 . 1 2.2 F AND G SWITCH ADJUSTME NT For proper electrical operation, the F and G mechani cally operated switches must operate at the proper point in the closing cycle. If these switches are to be replaced, measure the distance between the tip of the switch button and the bracket on which they are mounted.
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S E C T I O N 7 - B re a k e r M ai n t e n a n c e ( C o nt A D J U S T M E NT S L E E V L U B R I C A Ti O C O LL A...
SECTION 7-Breaker Maintenance (Cont.) 7 . 1 4 BUFFER ASSEMBLY When the breaker is closed , the energy in the c losing When the break � r is opened, the end plate assembly is spring i s transferred to the m a i n s h aft thro u g h the driven against the opposite end of the buffer assembly.
SECTION 7-Breaker Maintenance (Cont.) NEOPRENE WASHERS 7 . 1 4 . 1 B U FF E R ADJUSTMENT WASHERS Referring to Fig. 40, with the b reaker closed and the m echanism not reset, a . 005" clearance m ust exist be tween the end p late assem bly and the buffer nut as shown.
SECTION 8-Contact Maintenance 8 . 1 ARC C H UTE R E M OVAL A N D I N S P ECTIO N Breakers subjected to frequent interruption of high cur Th ere are two types of arc ch ute const ru cti on used rents may eventually requ ire replacement of their contacts.
SECTION 8-Contact Maintenance (Cont.) CONTACT ADJUSTM ENT - AKR 30/30H & AKRU The contact structure of the AKR 30 and the AKRU 30 breakers is s lightly different from the AKR 30H. Referring to Fig. 44 A & B, both structures use one moveable contact arm, and two stationary arcing contacts.
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SECTION 8-Contact Maintenance (Cont.) C ON TACT A D J U STM ENT AKR30L, A K R50/50H & A K R U 50 5. Attach a continuity checker (bell-set, light, or ohm The contact breaker shown i n F i g . 47 is used by meter) between the upper and lower stud.
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CONTACT ADJUSTMENT AKRT 50/SOH 1 . Open the breaker. The contact structure shown in Fig. 48 is used by all AKRT 50 breaker types. This structure is similar to the AKR 2 . Arrange the breaker tor slow-closing. 50 structure. There are two movable contact arms, each 3.
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SECTION 8-Contact Maintenance (Cont.) 8 . 5 STATI ONARY CONTACT I DE NTIFIC AT I O N T h e stationary arc i n g , i ntermediate, a n d m a i n contacts each have a d i fferent function d u r i n g cu rrent con d u ction and c u rrent i nterruption .
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8 . 6 CONTACT R E P LAC E M E NT 8. 7 CONTACT R EP LACEMENT- AKR 30L, AKA 30/30H/30L & AKRU 30 AKR 50/SOH , AKRU 50 & AKRT 50 Refer to Stationary Contact Identif ication , Section 8.5 Refer to Stationary Contact Identification, Section 8.5, before replacing any stationary contacts.
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SECTION 8-Contact Maintenance (Cont.) FIG. SOB - ARC RU N N ER REMOVED FIG. SOC - ARCING CONTACT PIVOT REMOVED...
SECTION 9-Fused Breakers S P ECIAL 2500A FUSE FOR AKRU-50 There are two types of fused breakers; AKRU 30, 800 ampere frame and AKRU 50, 1 600 ampere frame. Except This fuse provides a melti ng time-current characteristic for the open fuse lockout device and the i ntegrally that coordinates with 1 600A trip devices.
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CAUTION : WHEN REPLACING THE F U S E I N THE LEFT POLE (FRONT VIEW) O F THE BREA KER, SECTION 9-Fused Breakers (Cont.) NO TE PA R TI C UL A R L Y THA T THIS F U S E I S MOUN TED DIFFERENTL Y THAN THE O THER TWO FUSES.
SECTION 9- Fused Breakers (Cont.) OPEN FUSE LOCKOUT DEVICE This device automatically trips the fuse breaker if one of the fuses opens. When this happens, the breaker is locked open until the reset button of the phase i nvolved is pushed. The breaker should not be reclosed , of course, u ntil the opened fuse is replaced .
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SECTION 9-Fused Breakers (Cont.) ARMAT U R E R E S ET BUTION FIG. 56A-DETAILS FIG. 568-INSTALLED TYP E A OR 8 B R EAKER OFLO DEVICE...
SECTION 1 0-Type SST Overcurrent Trip Device The SST is a solid-state, direct-acting, self-powered trip - - - - - device system . The SST system consists of the SST pro grammer unit, current sensors, and a flux shifter trip de OYERlMD vice .
SECTION 1 0-Type SST Overcurrent Trip Device (Cont.) M O U N T I N G BRACKET -... .. FIG. 59 - AKR-58-30 1 0.2 C U R R ENT S ENSORS The SST system uses two types of current sensors, a phase sensor and a ne utral sensor.
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B R E A K E P MOU N T E D FIG. 60 SST PHASE SENSOR WITH TAP BOARD E Q U I P MENT MOUNTED 600 - 1 600 300 - eoo SHORTING STRAP FIG. 62 N EUTRAL SENSOR 1 0 0 - 3 0 0 SECONDARY DISCONN ECT...
1 0.2.1 REPLAC E M ENT O F C U R R ENT S E N SO R S d) When replac i n g the stud con nector, tig hten the Referri n g to F i g . 63, rep l acement o f i n d iv i d u al SST ±...
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So long as the act u ator rem a i n s i n the Reset posi 1 . Remove t h e f l ux s h i fter leads f rom t h e h arness. tion, the b reaker can be c l o sed and opened n o rmal l y 2.
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SECTION 1 0-Type SST Overcurrent Trip Device (Cont.) Bottom view Top view 1 . Actuator 4 . Trip shaft 2 . Trip rod adjuster end 5 . A ctuator arm 3 . Trip paddle 6 . Reset linkage FLUX S H I FT TRIP DEVIC E COMPON ENTS FIG.
1 0.4 TROUBLESHOOTING W h e n malfu nction ing i s suspected t h e fi rst step i n b) using the Ground Fault Defeat Cable as shown troubleshoot ing is to exam i ne t h e c i rc u it breaker a n d its in Fig.
SECTION 1 0-Type SST Overcurrent Trip Device {Cont.) 1 0.4.1 SST TEST SET 1 0.4.2 R ES ISTANCE VAL U ES The TAK-TS1 and TAK-TS2 Test Sets are portable in stru m ents des ig ned for field-checking the t i m e-cu rrent For use in troubleshooting, the Com mon to Tap resist...
1 0.4.3 FALSE TRIPPING-BR EAKERS EQUIPPED WITH G RO U N D FAU LT c) Verify that the harness connections to the sensors When nuisance tripping occurs on breakers equipped meet the polarity constraints i ndicated by the cabling dia with the G round Fault trip element, a probable cause is the gram, i .
SECTION 1 0-Type SST Overcurrent Trip Device - - - -- q, B q, c PROGRAMMER FLUX SHIFT UNIT TRIP DEVICE BREAKER (48V. de) BACK FRAME � (TO SCR ANODE) LEFT POLE CURRENT WHITE SENSOR BLACK WHITE BLACK WHITE BLACK _ _ _ _ _ HARNESS CON NECTOR...
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SST, see Fig. 74. 3. Neutral sen sors are not req u i red becau se there is no G round Fau l t fu nction.
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TABLE 9 ECS TRIP CHARACTERISTICS Trip Rating ECS PROGRAMMER ADJUSTMENT RANGE (Set Points) in Amperes • Sensor Rating Long Time Short Time - - - - - - Frame ® ® Instantaneous Breaker Size • Pick Time Pickup Time Pickup Type Sensor (Amperes)
SECTION 1 2- MicroVersaTrip ™ Trip Device 1 2.1 .1 FAU LT TRIP I N DICATORS The M ic roVersaTri p is a solid-state , d i rect-act i n g , self-powered tri p device system . T h e M icroVersaTrip The optional fault trip indicators are similar to the SST system consist s of the M ic roVersaTr i p p rog ram mer, indicators.
The remote fault ind ication switch leads are brought out the bottom of the M icroVersaTrip program mer as shown in Fig . This switch lead harness is pl ugged i nto the mati ng con nector on the breaker, see Fig . 79. The switch leads are brought out from the breaker through the Program mer Secondary Discon nect shown in Fig .
SECTION 1 2- MicroVersaTriprM Trip Device (Cont.) 1 2.2 C U R R ENT SENSORS The tapped and fixed phase sensors have a polarity as The cu rrent sensors su pply the power and signal in sociated with their windings. Their COMMON terminal is the put necessary to o perate the trip system .
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TAB L E 1 1 TRIP FU NCTIONS AVAILABL E ADD TO BASIC FUNCTIONS BASIC FUNCTIONS Z1 -or-Z2-or-Z STD.-or-5-or-H-or-M G-or-GR A 1 -or-A2-or-A3-or-A • Adjustable Current Setti ng • Adj Long-Time Pickup • LONG Adj Long-Time Delay • TIME • Remote Long-Time Timing Light •...
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SECTION 1 2- Micro Versa Trip Trip Device (Cont.) TAPPED FIG. 83 - M I C ROVERSAT R I PTI'' PHASE FIG. 85 - TYPICAL N E UTRAL S ENSOR SENSORS A M P E R E RATING CONNECTIONS FIG. 84 - 'H'-OPTION P HASE SENSOR...
Si nce t h e neutral sensor i s m o u n ted separately from the breaker, a d i scon nect means i s req u i red to con nect its o u t p u t to the b reaker. F i g . 86 shows the b reaker and eq u i pment mou nted 4th w i re secon dary d i scon nect u sed w i t h the M i c roVersaTri p syste m .
SECTION 1 2- MicroVersaTriprM Trip Device (Cont.) 1 2.3 FLUX SHI FTER TRIP DEVICE Once it has been establ ished that the circuit breaker can be opened and closed normally from the test position, The only difference between the MicroVersaTrip and attention can be directed to the trip device proper.
SECTION 1 2- MicroVersaTrip ™ Trip Device (Cont.) 1 2.4.2 FALSE TRIPPING- B R EAKERS EQU I P P E D WITH G ROU ND FAU LT When n u isance tri pping occu rs on breakers eq u i p ped with the G round Fault tri p element, a p robable cause is the existence of a false "g round"...
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SECTION 1 2- MicroVersaTrip ™ Trip Device (Cont.) 1 2.5 CABLI N G DIAG RAM S � B 4> C �A PROGRAMMER A. A. .A -- -- -- FLUX SHIFT UNIT r "f - 1- t - 1 TRIP DEVICE :�...
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PROGRAMMER FLUX SHIFT UNIT TRIP DEV I CE �- - - - - - HARNESS PR O GR AMMER CO NN EC TOR CO N NE CT OR AM P 1 -35 0 35 6 -9 EQUIPMENT -MOUNTED NEUTRAL SENSOR 4-WIRE LOAD FIG.
& & SECTION 12- MicroVersaTrip™ RMS-9 Epic MicroVersaTrip™ Device (Cont.) BREAKER PROGRAMMER GROUND FAULT DEFEAT M O D U LE HARNESS U N IT CAT. NO. TVTGD9 CONNECTOR , - - --, � I I o-+-< r -t I o-+-< �...
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PROGRAMMER REMOTE FAULT MICRO-VERSA TRIP SECONDARY INDICATION PROGRAMMER DISCONNECT CONNECTOR EQUIPMENT BREAKER - - - - - YELLOW OVERL OAD SHORT CIRCUIT GREEN GREEN BLUE OVERLOAD BLUE PICKUP _ _ _ _ 1 -35024 6 -9 1 -350239-9 1 - 350 242 -9 1 -350235-9 FIG.
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& SECTION 1 3-RMS-9 E p ic MicroVersaTri p ® 1 3.1 .1 FAULT TRIP INDICATORS The RMS-9/Epic M ic roVersaTri p® is a solid-state, d i rect-acting, self-powered t r i p device system. The RMS-9 The optional fault tri p indicators are similar to the system consists of the RMS-9 programmer, current sen...
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& SECTIO N 1 3-RMS-9 Epic M icroVersaTrip® {Cont. ) 1 3.2 CURRENT SENSORS The current sensors supply the power and signal i nput n ec essary to o p erate the t r i p syst e m . L i ke t h e M icroVersaTrip '), t h e RMS-9 and Epic MicroVersaTrip(' uses a phase and neutral sensor.
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& SECTIO N 1 3- RMS-9 Epic M icroVersaTrip ® TAB L E 1 1 TRIP FUNCTIONS AVAILABLE BASIC FUNCTIONS ADD TO BASIC FUNCTIONS G-or-GR A 1 -or-A2-or-A3-or-A Z1 -or-Z2-or-Z STD.-or-5-or-H-or-M • Adjustable Current Setting • Adj Long-Time Pickup • LONG Adj Long-Time Delay •...
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FIG. 1 03 - TYPICAL N EUTRAL SENSOR Fig. 1 03 shows the neutral sensor. The neutral sensor is required when integral ground fault protection is used on single phase-three wire or three phase-four wire sys tems. It is inserted into the neutral conductor and therefore is separately mounted in the cable or bus com partment.
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Socket P I N Zone In p uts Zone PROGRAMMER Selective FLUX SHIFT UNIT �-- - - - � TRIP DEVICE Interlock Zone Out p uts S p are E p ic � � ��� �6� 6 PRO GRA MM ER CON NE CTO R EOUIPM AMP 1-350356 -9...
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SECTION 1 4-MicroVersaTrip® Plus and M icroVersaTrip® PM Trip U nits The MVT-Pius/MVT-PM is a sol id-state d i rect-acting self-powered trip device system . The system consists of the MVT- Plus/MVT- PM programmer, current sensors and a flux sh ifter trip device. Figure 1 1 0 shows location of features on programmer.
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SECTION 1 4-MicroVersaTrip ® Plus and MicroVersaTrip® PM Trip Units 1 4.2 TESTING Testing of M icroVersaTrip® Plus and MicroVersaTri p® PM tri p un its may be performed with the trip unit installed in the circuit breaker, the rating plug installed in the tri p unit, and the breaker carrying current.
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SECTIO N 1 4-M icroVersaTri pTM Plus and M icroVersaTripT\1 PM Trip Un its 1 4.4 TRIP UNIT REMOVAL AND REPLACEMENT Socket The programmer m o u nts to the u p per l eft of the breaker Class 1 1 5 . as shown in F i g .
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SECTION 1 4-MicroVersaTrip® Plus a nd M icro Versa Trip® PM Trip Units TAPPED COMMON TERM I NAL FIG. 1 1 5 FIG. 1 1 6 1 4.5 PHASE C U RRENT SENSORS The fixed phase sensors are available with an additional winding.
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SECTIO N 1 4-MicroVersaTrip® Plus and M icroVersaTrip® PM Trip Units 1 4.7 RATING PLUG REMOVAL AND RE 1 4.6 NEUTRAL C U RRENT SENSORS PLACEMENT CAUTION: Neutral current sensors are req uired for three phase, four-wire systems . When the trip u n it is con nected CAUTION: Removal of the rating plug while the breaker to a three-phase, three-wire system, the neutral sensor is carrying current reduces the breaker's current-carrying...
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SECTION 1 4-MicroVersaTrip® Plus and M icroVersaTrip® PM Tri p Units 1 4.8 TRIP U N IT FUNCTIONS - G round-fault protection, with or without 1 2T M icroVersaTri p® P l us and M icroVersaTrip® PM tri p units have specific standard and o ptional fu nctions.
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SECTIO N 1 4-MicroVersaTrip® Plus and M icroVersaTrip® PM Trip Units 1 4.9 TROUBLE-SHOOTI NG G U I D E The following g u i d e is provided for trouble-shooting and isolating common problems. It does not cover every possi ble condition .
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TABLE 23 SH U NT TRIP AND UNDERVOLTAGE DEVICE OPERATING C U R RENTS SHUNT TRIP UNDER VOLTAGE 0 .. > O cr� Current Current - ..- G> N (Amps) (Amps) :::l :t: e > Operating Inrush Sealed Inrush Sealed Operating...
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TABLE 25 I N STANTAN EOUS U N DERVOLTAG E DEVICE SETT I NGS COI L MAXI MUM DROP OUT RATI NG PIC K U P VOLTAGE RANGE 7-1 4 24 VDC 1 4-29 48 VDC 38-75 1 25 VDC 1 06 47-93 1 55 VDC...
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, the m a tter s h o u l d be referred to the GE Company.
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GEK-64459C Maintenance Manual Low Voltage Power Circuit Breakers Types AKR-30/50 AKRT-50...
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Low Voltage Power Circuit Brea kers Table of Contents Page Page SECTION 1 SECTION 7 1 .0 INTRODUCTION Aux i l iary Switch 7.6. 1 Replacement 1 . 1 I nspection and Mai ntenance 7.6.2 Adj ustment 1 .2 Renewal Parts Shunt Tri p SECTION 2 7.7.
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Page Page SECTION 1 0 SECTIO N 1 4 1 4 .0 1 0.0 TYPE SST OVERCU RRENT M I C ROVERSATRIP . PLUS AND MIC ROVERSATRI P PM TRIP U N ITS 77 TRIP D EVICE 1 4 . 1 Tri p U nit 1 0 .
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SECTION 1 - lntroduction A basic i nspection should consist of the following: a. Visual Check - Look for dirt, grease or other foreign These instructions provide the mai ntenance procedures material on any breaker parts. Check insulati ng su rfaces and describe the operation of the 800 thru 2000 amp frame for conditions that could degrade i nsulating properties size type AKA low voltage power circuit breakers listed i n...
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The drawing n um ber appears on the breaker nameplate and can be obtained from GE. FUSED/NON FUSED 2 . 1 FRAME SIZE Fused breakers are identified as either AKAU 30 (800 ampere frame size) or AKAU 50 ( 1 600 ampere frame size).
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SECTION 2-General Description {Cont.) 2 .5 TRIP DEVICE MOUNTING Type AKA breakers are designed for either drawout or There are several types of soli d-state, direct-acting, self stationary mounting. Drawout breakers (See Fig. 4) are powered trip device systems associated with AKA equ ipped with features which make them easy to instal l i n breakers.
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SHORT CIRCUIT RATI NGS Short circuit ratings vary with the applied system vol tage. On 240 VAC syste ms they are also dependent upon whether the overcurrent trip device contains an i nstan taneous tri p element. See Table 4 . TAB L E 4 - B R EAKER I NTE R R U PTI ON RATI NGS 3$ INTERR U PTION RATING KA RMS SYMM ETRICAL...
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SECTION 3 .0-Stora g e , Safety, 3 . 1 Safety M a i nten ance Each user m ust maintain a safety program for the protec tion of personnel, as wel l as other equipment , from the I t i s recom mended that the breaker be put into service potential hazards associated with electrical equipment.
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3 . 2 Maintenance Both long and short term maintenance o f all electrical I nstruction books supplied by manufacturers address equipment is essential for reliabi l ity and safety. Mainte com ponents that would normally req uire service or main nance programs must be tuned to the specific application, tenance during the useful life of the equipment.
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SECTION Drawout Breaker Interchangeability I n general, drawout breakers of the same type and rating are i nterchangeable in their equi pment compartments ; drawout breakers of different frame sizes are not i nter changeable. To prevent inserting the wrong type breaker i nto a drawout compartment, suitable "...
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SECTIO N 1 4-M icroVersaTrip® Plus and M icroVersaTri p® PM Trip Units 1 4.9 TRO U BLE-SHOOTI NG G UI DE The following guide is provided for trouble-shooting and isolating common problems. It does not cover every possi ble cond ition. Contact the Customer Support at 800-843-37 42 if the problem is not resolved by these procedures.
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SECTION 1 5-EC Trip Device Type E C overcurrent trip devices are magnetically The standard EC trip device for breaker frames up to operated, using a series coi l or single conductor, and an 2000 amps is the type EC-2A, see Fig. 1 1 9. An optional trip associated magnetic structure to provide tripping force.
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SECTION 1 5-EC Trip Device (Cont . ) FIG. 1 2 1 OVERC U R R ENT TRIPPING DEVICE - EC-2A...
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SECTIO N 1 5-EC Tri p D evice {Cont.) comes this restraining force, the armature movement is further 1 5.2 SERIES OVERCURR ENT TRIPPING retarded by an escapement mechanism which produces an in DEVICE EC-1 verse time delay characteristic. The mechanism is shown on Each series overcurrent tripping device is enclosed in a Fig.
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SECTIO N 1 5-EC Trip Device (Cont . ) 1 5.2.3 INSTANTANEOUS TRIPPING 1 5.3 POSITIVE TRIP ADJUSTMENT (a) Adjustable instantaneous tripping takes place after the Before attempting any checks or adjustments on breaker with magnetic force produced by an overcurrent condition, over EC trip devices, the breaker mechanism and trip latch should be checked to assure their proper functioning so that the breaker comes the restraining force of the calibration spring which can...
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SECTIO N 1 5-EC Tri p Device (Cont . ) normal direction, the magnetic flux of the series coil and the 1 5.4 R EVERSE CUR RENT TRIPPING DEVICE magnetic flux of the potential coil produce a torque which tends The device is enclosed in a molded case and is mounted on to rotate the armature counterclockwise.
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SECTIO N 1 5-EC Trip Device (Cont . ) 1 5.4.1 ADJ USTM ENTS 1 5.6 TRIP DEVICE REPLACEMENT & The only adjustment to be made on the reverse current de Overcurrent devices on AKR30 AKR50 breakers may be vice is to make sure that the trip rod has a minimum overtravel dismounted by removing the fastening hardware at the rear of of 1 /32 in.
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SECTIO N 1 6-Eiectrical Characteristics 1 8 - Char g in g and Closin g Operatin g Currents TABLE MOTOR ANTI-PUMP CONTROL "W" "X" CLOSING > Current (Amps) RELAY RELAY SOLENOID "' ;;; .., Cl> c; ..C QI .., .., c;...
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TABLE 23 SHUNT TRIP AND UN DERVOLTAG E DEVICE OPERATING CURR ENTS UNDER VOLTAGE SHUNT TRIP > " Current Current 8 � Cll N (Amps) (Amps) � � ij. :r ·- > Inrush Operating Inrush Sealed Sealed Operating Open Closed Voltage range Open Closed...
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TABLE 25 I N STANTAN EOUS UNDERVOLTAG E DEVICE SETTINGS COI L MAXI M U M DROP OUT RATING PIC K U P VOLTAGE RANGE 7- 1 4 24 VDC 1 4-29 48 VDC 1 25 VDC 38-75 1 06 47-93 1 55 VDC 1 32...
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Should furth er information be desired or should particular problems arise which arc not covered sufficien tly fi:lr the purchaser's purposes, th e matter should be referred to the GE Company. GE Electrical Distribution & Control General Electric Company 4 1 Woodford A ve., Plainville, CT 06062...
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ELECTRICAL CLOSING SECTION 5-Breaker Operation On electrically operated brea kers the closing springs are charged by a gear motor. With the springs discharged, voltage appl ied to the control circuit will energize the motor through the " G " switch contacts - see Fig. 9 . The motor, A breaker may be eq u i pped to operate either manually through the gear reduction output crank, compresses the or electrical ly.
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5.2.1 ALTERNATE CONTROL C I RC U IT USED A second type of electrical control is shown i n Fig. 9A equipped) or by a remote closing switch . Operation of the , closing switch energizes the K-relay, which i n turn ener for all control voltages except 250 volts D .C .
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M ECHAN ISM O P E RATION Figures 1 OA, 1 OB and 1 OC show the mechan iSm com .. ponents in the C losed, Tri p ped and Reset positions. The closing spring is in the charged position for all of these d etails.
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SECTION 5-Breaker Operation (Cont.) FIG . 1 2 - ROLLER ENGAG ED WITH CLOSING P ROP There is a ratchet asse mbly attached to the camshaft Rotate the camshaft using the m aintenance handle until extension . This ratchet is normally driven by the breaker's the ratchet assembly roller engages with the prop.
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SECTION 6-lnterlocks AKR breakers are equipped with safety interlock devices that are requi red by Industry Standards and Certifying Au thoriti es. I nterlock devices for special applications are also avai lable as options. The standard interlock devices de scri bed below are used only on drawout breakers. Stati on ary breakers have no required interlocks.
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SECTION 6-lnterlocks (Cont.) • I NTERLOCK FIG. FIG. 1 6 - POSITIVE INTERLOCK RACKING SCREW COVER INTERLOCK CLOSED POSITION cran k pin reaches the end of the slot i n the li nkage. Continued motion of the racking mechanism causes the li nkage to rotate the lever which moves the closing sole...
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DISCONN ECT POSITION I NTER LOCK The function of the D iscon nect Position I nterlock is to block the RACKING SCREW cover open when the racking mechanism is in the D I SCONN ECTED position. When the cover is held open, the T R I P button is depressed. The mechanism is held trip-free and there is no contact arm movement wh en the closing spring is discharged by the Closing Spring interlock.
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SECTION 6-lnterlocks (Cont.) KEY INTERLOCK-STATIONARY When the breaker is in the CLOSED position, the fly B REAKER wheel assembly item #2 is away from the lever item #6. The lever is spring loaded and rotates clockwise causing its pin to block the l oc k bolt extension. The function of the Key I nterlock is to prevent an open breaker from being closed when the lock bolt is extended and its key is removed.
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SECTION 7-Breaker Maintenance (Cont.) MANUAL HANDLE ADJ USTM ENT The areas requiri ng l ubrication are: The adjustment li nkage connects the handle assembly to Contacts Pivots - A thin fi l m on the stationary the chain drive mechanism which turns the cam shaft. The and movable contact assembly pivot surfaces.
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SECTION 7 -Breaker Maintenance (Cont.) DRAWO UT M ECHANISM POSITION Remove the hex-head bolt only, do not remove or loosen Maintenance or i nspection should be conducted with the the slotted head screw shown in Fig. 2 1 . Removal of the slotted head will cause the closing spring to become d is...
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SECTION 7- Breaker Maintenance (Cont.) PRI MARY DISCONN ECTS The 800 ampere breakers use four primary discon nect fingers per terminal. The 1 600 and 2000 ampere breakers Pri mary disconnects are found only on drawout break use eight fingers per term inal . Fig. 22 shows a line and ers.
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The GE SB-1 2 replacement switch should have its shown in Fig. 26 . 766" to .797" Note that this di mension...
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ELECTROSWITCH TYPE 1 01 Adjustment i s the same as the GE S B 1 2 except that when the switch "A" contacts touch , the breaker arcing contacts must be within 0 to .250 inches of c losing.
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SECTION 7 -Breaker Maintenance (Cont.) DROPOUT VOLTAGE: � On AC devices the dropout level will fall within the requ i red limits (30 % to 60% of the coil rating) if the picku p is set properly. On DC devices, the d ropout level may need independent adjustment.
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STOP OPEN GAP INSERT W I R E GAGE ADJ USTM ENT ± 005 D I A .201 P I N FIG. 328 - OPEN GAP CHECK FIG. 320 - POSITIVE TRIP CHECK When i nstalled, the voltage to be monitored is connected across term inals No.
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SECTION 7 -Breaker Maintenance (Cont.) 3. Check resis t ance of the disconnected undervoltage device. See Table 5 for values. See i nstruction Sheet G EH-4545 for more detai led infor mation, including schematic diagrams and circuit descrip tion. The undervoltage device must be cal i brated through the time-delay unit after the device pick up has been adjusted.
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SECTION 7-Breaker Maintenance (Cont.) 7.1 1 .3 REPLACEM ENT The mechanism i s reset by disengaging the side latch l i nk from the upper latch link or by closing the breaker if a The bel l alarm is mounted on the right hand side of the locklever is not provided.
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SECTION 7-Breaker Maintenance (Cont.) 7.1 2.1 COM PON ENT REPLACEM ENT To gain access to the electrical control components, the breaker's front escutcheon m ust be removed. Type B and D breakers requ i re that both the deep molded escut cheon and the shal low steel escutcheon be removed.
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F AND G SWITCH ADJ USTMENT 7.1 2.2 For proper electrical operation, the F and G mechani cally operated switches must operate at the proper point in the closing cycle. If these switches are to be replaced, measure the distance between the tip of the switch button and the bracket on which they are mounted.
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S E C TI O N 7 - B r e a k e r M a i n t e n a n c e ( C o n t . L U B Ri C A Ti O C O L L A l U B RI C A TI O...
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SECTION 7-Breaker Maintenance (Cont.} BUFFER ASSE M B LY 7. 1 4 When the breaker is closed, the energy in the closing When the breaker is opened, the end plate assembly is " driven against the opposite end of the buffer assembly. spring i s transferred to the main shaft thro u g h the mechanism.
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SECTION 7-Breaker Maintenance (Cont.) NEOPRENE WAS H E RS 7 . 1 4. 1 B U FFER ADJ USTME NT Referring to !=ig. 40, with the breaker c losed and the mechanism not reset, a . 005 " c learance must exist be tween the end p late assembly and the buffer nut as shown.
SECTION 8-Contact Maintenance ARC CHUTE REMOVAL AND INSPECTION Breakers subjected to frequent i nterruption of high cur There are two types of arc chute construction used on rents may eventually req uire replacement of their contacts . the 800 thru 2000 ampere breakers. They are the cerami c The general rule for determi ning need of replacement is type shown i n Fig.
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SECTION 8-Contact Maintenance (Cont.) CONTACT ADJUSTM ENT AKR 30/30H & AKRU 30 The contact structure of the AKR 30 and the AKRU 30 breakers is slightly different from the AKR 30H. Referring to Fig. A & B, both structures use one moveable contact arm, and two stationary arcing contacts.
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SECTION 8-Contact Maintenance (Cont.) & CONTACT ADJUSTM ENT AKRU 50/SOH The contact structure shown in Fig. 47 is used by all 5. Attach a conti nuity checker (bell-set, light, or ohm AKR50 breaker types. This structure uses two movable meter) between the upper and lower stud.
CONTACT ADJUSTMENT AKRT 50/SOH 1 . Open the breaker. The contact structure shown in Fig. 48 is used by all AKRT 50 breaker types. This structure is similar to the AKR 2. Arrange the breaker for slow-closing. 50 structure. There are two movable contact arms, each acting against single stationary arcing and intermediate 3 .
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SECTION 8-Contact Maintenance (Cont.) STATIONARY CONTACT I DENTI FICATION The stationary arcing, intermediate, and main contacts each have a different function d uring current conduction and current i nterruption. For this reason, these contacts are made using different material compositions. Also, the different functions require that the contacts be replaced in configurations shown i n Figs.
CONTACT R EPLACEM E NT CONTACT R E P LACEMENT- AKA 30/30H & AKRU 30 AKA 50/SOH , AKRU 50 & AKRT 50/SOH Refer to Stationary Contact Identification , Section 8.5 Refer to Stationary Contact Identification, Section 8.5, before replacing any stationary contacts. before replacing any stationary contacts.
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SECTION 8-Contact Maintenance (Cont.) FIG. SOB - ARC RU N N ER REMOVED FIG. SOC - ARC I N G CONTACT PIVOT REMOVED...
SECTION 9-Fused Breakers There are two types of fused breakers ; A K R U 30, 800 SPECIAL 2500A FUSE FOR AKRU-50 am pere frame and AKRU 50, 1 600 ampere frame. Except This fuse provides a melting time-current characteristic for the open fuse lockout device and the i ntegrally...
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CAUTION: WHEN REPLACING THE FUSE I N THE LEFT POLE (FRONT VIEW) OF THE B REAKER, SECTION 9-Fused Breakers (Cont.) N O TE PA R TI C UL A R L Y THA T THIS F U S E I S MOUNTED DIFFERENTL Y THAN THE O THER TWO FUSES.
SECTION 9- Fused Breakers (Cont.) OPEN FUSE LOCKOUT DEVICE This device automatically trips the fuse breaker if one of the fuses opens. When this happens, the breaker is locked open until the reset button of the phase involved is pushed . The breaker should not be reclosed, of course, until the opened fuse is replaced.
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SECTION 9-Fused Breakers (Cont.) ARMAT U R E RESET BUTTON FIG. 56A-DETAILS FIG. 568-I NSTALLED TYPE A OR B B R EAKER OFLO DEVICE...
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SECTION 1 0-Type SST Overcurrent Trip Device �- - - - - - The SST is a s o l i d-state, d i rect-acti n g , self-powered trip device syste m . The S S T system consists of t h e SST pro grammer u n it, c u rrent sensors, a n d a flux sh ifter t r i p de...
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SECTION 1 0-Type SST Overcurrent Trip Device (Cont.) M O U N T I N G � BRACKET FIG. 59 - AKR-58-30 1 0.2 C U R R ENT S ENSORS The SST system uses two types of cu rrent sensors, a phase sensor and a neutral sensor.
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B R E A K E F' M O U N T E D FIG. 60 - SST PHASE S ENSOR WITH TAP BOA R D EQUI PME N T MOU N TED 600 - 1 600 FIG. 62 - N EUTRAL SENSOR 10 0 - 3 00 SECONDARY DISCONNECT FIG.
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1 0. 2 . 1 R E P LAC EM ENT O F C U R R E NT S E N SO R S d) When re p l ac i n g t h e stud connector, t i ghten t h e Referri ng t o F i g .
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So long as the act u ator re m a i n s i n the Reset posi 1 . Remove t h e flux s h i fter leads from the h arness. tion, the b reaker can be c l osed and opened norm a l l y 2 .
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SECTION 1 0-Type SST Overcurrent Trip Device (Cont.) Bottom view Top view 1 . A ctuator 4 . Trip shaft 2 . Trip rod adj uster end 5 . Actuator arm 3 . Trip paddle 6 . Reset linkage FIG. 65 - F LUX S H I FT TRIP DEVICE COMPON ENTS T R I P PAJDLE IN "...
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1 0.4 TROUBLESHOOTI N G When malfunctioning i s suspected t h e fi rst step i n b) using the Ground Fault Defeat Cable as shown troubleshooti n g i s t o exam i ne the c i rc u i t breaker and its in Fig.
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SECTION 1 0-Type SST Overcurrent Trip Device (Cont.) 1 0.4.1 SST TEST SET 1 0.4.2 R ES ISTANCE VAL U ES The TA K-TS1 and TA K-TS2 Test Sets are portable in struments desig ned for field-checking the t i me-cu rrent For use in troubleshooting, the Common to Tap resist...
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1 0.4.3 FALSE TRIPPI NG-B R EAKERS EQUIPPED WITH G RO U N D FAU LT c) Verify that the harness connections to the sensors When nuisance tripping occurs on breakers equi pped meet the polarity constraints i ndicated by the cabling dia with the G round Fault trip element, a probable cause is the gram, i .
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SECTION 1 0-Type SST Overcurrent Trip Device cp S cp C - - - - PROGRAMMER FLUX SHIFT U N IT TRIP DEVICE BREAKER � BACK FRAME (48V. (TO SCR ANODE) LEFT POLE CURRENT WHITE SENSOR BLACK WHITE BLACK WHITE BLACK HARNESS PR O GR AM ME R...
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SECTION 1 1 -Type ECS Overcurrent Trip Device The ECS is a so l id-state, d i rect-act i n g , sel f-powered trip devi ce system . The ECS system consi sts of the ECS p rog rammer u n i f shown in Fig. 72, cu rrent sensors, and a flux s h i fter trip device.
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TABLE 9 ECS TRIP CHARACTERISTICS Trip Rating ECS PROGRAMMER ADJUSTMENT RANGE (Set Points) in Amperes • Sensor Rating Long Time Short Time Frame ® ® Instantaneous Breaker Size Pick (•L) Time Pickup Time Pickup Type Sensor (Amperes) Delay Delay Am � ere Multiple Band Multiple...
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SECTION 1 2- MicroVersaTrip Trip Device FAU LT TRIP IN DICATORS 1 2. 1 . 1 The M i c roVersaTri p is a solid-state , d i rect-acti n g , self- powered trip device system . The M icroVersaTri p The optional fault trip indicators are similar t o t h e SST system consists of the M icroVersaTri p p rog rammer, indicators.
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The remote fault indication switch leads are brought out the bottom of the MicroVersaTrip program mer as shown in Fig. 78. This switch lead harness is plugged into the mating connector on the breaker, see Fig. 79. The switch leads are brought out from the breaker through the Programmer Secondary Disconnect shown in Fig.
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SECTION 1 2- MicroVersaTrip™ Trip Device (Cont.) 1 2.2 C U R R ENT SENSORS The tapped and fixed phase sensors have a polarity as sociated with their windings. Their COMMON terminal is the The cu rrent sensors supply the power and signal in put necessary to operate the trip system .
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TAB L E 1 1 TRIP FUNCTIONS AVAI LAB LE BASIC FUNCTIONS ADD TO BASIC FUNCTIONS G-or-G R A 1 -or-A2-or-A3-or-A Z1 -or-Z2-or-Z STD.-or-5-or-H-or-M • Adjustable Current Setti ng • Adj Long-Time Pickup • LONG Adj Long-Time Delay • TIME •...
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SECTION 1 2- M icro Versa Trip Trip Device (Cont.) TAPPED COMMON TER M I NAL FIG. 83 - M I C ROVERSATRI Pr"' PHASE FIG . 85 - TYPICAL N EUTRAL SENSOR SENSORS AMPERE RATING CONNECTIONS FIG . 84 - 'H'-O PTION PHASE SENSOR...
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S i n ce t h e neutral senso r is m o u n ted separately from the b reaker, a d i sconnect means i s req u i red to con nect its o u t p u t to the breaker. Fig. 86 s hows the b reaker and e q u i pment m o u nted 4th w i re second ary d i scon nect u sed w i t h t h e M i c roVersaTri p system.
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SECTION 1 2- MicroVersaTrip™ Trip Device (Cont.} 1 2.3 FLUX S H I FTER TRIP DEVICE Once it has been establ ished that the circuit breaker can be opened and closed normally from the test position, The only d ifference between the MicroVersaTrip and attention can be di rected to the tri p device proper.
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SECTION 1 2- Micro Versa Trip Trip Device (Cont.) 1 2.4.2 FALSE TRI PPI NG-B R EAKERS EQU I PP E D WITH G R O U N D FAU LT When nu isance tripping occu rs on breakers equipped with the G round Fault trip element, a p robable cause is the existence of a false "g round"...
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SECTION 1 2- MicroVersaTrip ™ Trip Device (Cont.) 1 2.5 CABLI N G DIAG RAM S cp A ci> C PROGRAMMER A- A- A FLUX SHIFT U N IT r 1 -[-t - 1 TRIP DEVICE :� � � � � � �- - - - - - �...
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A A A PROGRAMMER FLUX SH I FT UNIT r 1 -t - t- l TRIP DEV I CE �- - - - - , : � � � � ; � � }= = =)===)= LEFT POLE CURRENT SENSOR NEUTRAL SENSOR - - 1...
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& & SECTIO N 12- MicroVersaTrip ™ RMS-9 Epic MicroVersaTrip™ Device (Cont.) BREAKER PROGRAMMER GROU N D FAULT DEFEAT M O D U LE HARNESS UNIT CAT. NO. TVTGD9 CONNECTOR � I crt-< � I o-+-< � o---t- -< I o--1- --< �...
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PROGRAMMER REMOTE FAULT MICRQ-VERSA TRIP SECONDARY INDICATION PROGRAMMER DISCONNECT CONNECTOR EQUIPMENT BREAKER - - - -- - YELLOW OVERLOA D SHORT CIRCUIT GREEN GROU ND GREEN FAULT BLUE OVERLOAD BLUE PICKUP _ _ _ _ _ _ 1 -35024 6- 9 1 -350242-9 1 -3502 35 -9 1 -350239-9...
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& SECTION 1 3-RMS-9 E p ic MicroVersaTri p ® 1 3.1 .1 FAULT TRIP I N DICATORS The RMS-9/Epic MicroVersaTri p® is a sol id-state, di rect-acting, self-powered tri p d evice system. The RMS-9 The optional fau lt trip indicators are similar to the system consists of the RM S-9 programmer, cu rrent sen...
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& SECTIO N 1 3-RMS-9 Epic MicroVersaTrip® (Cont . ) 1 3.2 CURRENT SENSORS The current sensors supply the power and signal i n put nec essary to o p erate the tri p system . L i k e the M icroVersaTrip"' , the RMS-9 and Epic MicroVersaTri p ' uses a phase and neutral sensor.
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& SECTION 1 3-RMS-9 Epic MicroVersaTrip® TAB L E 1 1 T R I P FU NCTIONS AVAILABL E BASIC FUNCTIONS ADD TO BASIC FUNCTIONS STD.-or-S-or-H-or-M G-or-GR A 1 -or-A2-or-A3-or-A Z1 -or-Z2-or-Z • Adjustable Current Setting • Adj Long-Time Pickup •...
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FIG. 1 03 - TYPICAL N EUTRAL SENSOR Fig. 1 03 shows the neutral sensor. The neutral sensor is req uired when i ntegral grou nd fault protection is used on single phase-three wire or three phase-four wire sys tems. It is inserted into the neutral conductor and therefore is separately mounted in the cable or bus compartment.
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& SECTIO N 1 3-RMS-9 Epic M icroVersaTrip ® Device (Cont . ) 2 . Test the components of the R MS-9 system using Since the neutral sensor is mounted separately from the portable Test Set Type. The applicable test procedures breaker, a d iscon nect means is required to connect its are detailed in i nstruction Book G E K-97367.
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1 3.4.2 FALSE TRIPPING - BREAKERS 1 3.5 CABLING DIAGRAMS EQU IPPED WITH GROUND FAULT FLUX SHIFT q, s q, c UNIT PROGRAMMER ;__ ;__ ;__ When nu isance tripping occurs on b reakers eq uipped r t - 1- t- 1 TRIP DEVICE - - - - , t �...
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Socket P I N N o . Zone Zone Inputs PROGRAMMER Selective �- - - - - FLUX SHIFT UNIT TRIP DEVICE Interlock Zone Outputs Spare Epic -"i ��� ��ig 1-3503 56 - 9 PROGRAMMER CON NE CTO R 24 Ret NEUTRAL SENSOR 4 - WIRE LOAD 24 VDC...
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PM trip units req uire external 24 Vdc control power for MicroVersaTrip® P M trip u nits communicate d i rectly on operation. The fou r sources of such power are the the GE POWER LEADER'" communications bus. following. • Breaker current sensors provide...
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SECTION 1 4-MicroVersaTrip® Plus and MicroVersaTrip® PM Trip U nits 1 4.2 TESTING Testing of M icroVersaTrip® Plus and M icroVersaTrip® P M tri p units may be performed with the tri p unit installed in the circuit breaker, the rating plug installed in the trip unit, and the breaker carrying c urrent.
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SECTION 1 4-MicroVersaTrip™ Plus and M icroVersaTrip™ PM Trip U n its 1 4.4 TRIP UNIT REMOVAL AND REPLACEMENT Socket The programmer mounts to the u pper left of the breaker Class as shown in Fig. 1 1 5 . It mounts to the bracket assembly shown in Fig.
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SECTION 1 4-MicroVersaTrip® Plus and MicroVersaTrip® PM Trip U nits TAPPED FIG. 1 1 5 FIG. 1 1 6 1 4.5 PHASE C U RRENT SENSORS The fixed phase sensors are avai lable with an add itional winding. Th is winding is brought out to separate flag The current sensors supply the power and signal input term inals.
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SECTIO N 1 4-MicroVersaTrip® Plus and MicroVersaTrip® PM Trip Units 1 4.7 RATING PLUG REMOVAL AND RE 1 4.6 NEUTRAL C UR RENT SENSORS PLACEMENT CAUTION: Neutral current sensors are requ i red for three phase, four-wire systems. When the trip unit is connected CAUTION: Removal of the rating plug while the breaker to a three-phase, three-wire system, the neutral sensor is carrying current reduces the breaker's current-carrying...
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SECTIO N 1 4-MicroVersaTrip® Plus and M icroVersaTrip® PM Trip U nits 1 4.8 TRIP U NIT FUNCTIONS - Grou nd-fault protection, with or without 1 2T MicroVersaTrip® Plus and MicroVersaTrip® P M trip units have specific standard and optional functions. All trip - Zone-selective interlock, with g round fault only units share a series of interchangeable rating plugs.