FEDERAL PIONEER H-3 Maintenance manual

INSTRUCTIONS FOR THE CARE AND MAINTENANCE
OF H-3 AND HL-3 CIRCUIT BREAKERS
C-3-222-1
April 2000
FEDERAL
PIONEER
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BEFORE PLACING AN H-3 OR HL-3 AIR CIRCUIT BREAKER IN SERVICE, READ SECTIONS 1 THROUGH 6 OF THIS
INSTRUCTION MANUAL COMPLETELY AND PERFORM THE PRE-SERVICE INSPECTION (SEE SECTION 6).
THE PROPER INSTALLATION, MAINTENANCE AND OPERATION OF THESE BREAKERS IS A PRIME SAFETY
CONSIDERATION FOR THE PROTECTION OF PERSONNEL AND EQUIPMENT. REFERENCE TO THIS MANUAL AND ADHERENCE
ITS RECOMMENDATIONS WILL ENHANCE THE PERFORMANCE OF THESE BREAKERS UNDER ALL CONDITIONS.
THIS MANUAL DOES NOT PURPORT TO COVER ALL DETAILS OR VARIATIONS OF EQUIPMENT NOR TO PROVIDE
FOR EVERY POSSIBLE CONTINGENCY TO BE MET IN CONNECTION WITH RECEIVING, STORAGE, INSTALLATION, MAINTENANCE
OR OPERATION. SHOULD FURTHER INFORMATION BE REQUIRED OR PARTICULAR PROBLEMS ARISE WHICH ARE NOT COVERED
SUFFICIENTLY, PLEASE REFER TO SCHNEIDER ELECTRIC.
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CONTENTS
6. PRESERVICE INSPECTION
7. BASIC BREAKER MAINTENANCE
7.1 MAINTENANCE REQUIREMENTS
7.2BASIC MAINTENANCE PROCEDURE
8. DETAILED MAINTENANCE INSTRUCTIONS
8.1 CLOSING LINKAGE ECCENTRIC ADJUSTMENT
8.2 CLOSE LATCH ADJUSTMENT
8.3 TRIP LATCH ADJUSTMENT
8.4 DRAWOUT GATE INTERLOCK
8.5 SHUNT TRIP COIL
8.6 UNDERVOLTAGE TRIP DEVICE
8.7 LATCH CHECK SWITCH
8.8 MECHANICAL INTERLOCK
8.9 ANTI-SINGLE-PHASE DEVICE AND BLOWN FUSE
INDICATOR
8.10 USE OF LIMIT SWITCHES IN D.C. CONTROL CIRCUITS
9. MAINTENANCE ACCESSORIES AND SPARE PARTS
9.1 MAINTENANCE ACCESSORIES
9.2 SPARE PARTS
9.3 COIL DATA
1. GENERAL DESCRIPTION
2. RECEIVING - HANDLING - STORAGE - INSTALLATION
2.1 RECEIVING
2.2 HANDLING
2.3 STORAGE
2.4 MOUNTING
2.5 POWER TERMINAL CONNECTIONS
2.6 SECONDARY CONTROL CIRCUITS
3. BREAKER COMPONENTS AND CONTROLS
3.1 BREAKER SECTIONAL VIEW
3.2 CRADLE SECTIONAL VIEW
3.3BREAKER FACEPLATE AND CONTROLS
4. BREAKER OPERATION
4.1DRAWOUT MECHANISM - BREAKER INSERTION AND
REMOVAL
4.2GROUNDING CONTACT
4.3 SECONDARY CONTROL CONTACTS
4.4 BREAKER CLOSING
4.5 CLOSING MANUALLY OPERATED BREAKER
4.6 CLOSING ELECTRICALLY OPERATED BREAKER
4.7 MECHANICAL CLOSING INTERLOCKS AND PADLOCKING
4.8 BREAKER OPENING
4.9 REJECTION FEATURE
4.10 CLOSING SPRING DISCHARGE AND DRY RUNS
4.11FAULT PROTECTION
4.12 FUSE MOUNTING
4.13ANTI-SINGLE-PHASE DEVICE & BLOWN FUSE INDICATOR
4.14SHUNT TRIP COIL
4.15 AUXILIARY SWITCH
4.16 CLOSING COIL (CC)
4.17 CLOSING COIL LIMIT SWITCH AND ANTIPUMPING FEATURE
4.18 CLOSING SPRING CHARGING MOTOR (SCM)
4.19 SPRING LIMIT SWITCH (SLS)
4.20LATCH CHECK SWITCH (LCS)
5. OPTIONAL COMPONENTS
5.1 MECHANICAL OPERATIONS COUNTER
5.2 CELL SWITCHES
5.3 ANTIPUMP RELAY
5.4 UNDERVOLTAGE TRIP DEVICE
5.5 SAFETY INTERLOCK SWITCH (SLS)
5.6 OVERLOAD LOCKOUT DEVICE
5.7 DOOR INTERLOCK
5.8FACEPLATE KEY INTERLOCK AND CELL KEY INTERLOCK
5.9MECHANICAL INTERLOCK
5.10 SHUTTERS
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GENERAL DESCRIPTION
Type H - 3 POWER AIR CIRCUIT BREAKERS ARE SUITABLE FOR
CONTROLLING AND PROTECTING LOW VOLTAGE POWER CIRCUITS
UP TO 250 VOLTS DC AND 600 VOLTS AC. THEY ARE A MEANS OF
SAFELY SWITCHING LOADS AND AUTOMATICALLY CLEARING
CIRCUITS WHEN ABNORMAL CONDITIONS SUCH AS UNDER- VOLTAGE,
SUSTAINED OVERLOADS, AND SHORT-CIRCUITS OCCUR.
THE THREE MAIN FUNCTIONAL COMPONENTS OF THE TYPE H3
BREAKER ARE ITS MECHANISM, THE CONDUCTIVE MEMBERS AND THE
INTERRUPTING DEVICES.
1. THE MECHANISM IS DESIGNED TO RECEIVE ENERGY,
STORE IT, AND DELIVER IT TO CLOSE THE BREAKER CONTACTS WHEN
REQUIRED. UPON ACTIVATION OF THE TRIP DEVICE, THE MECHANISM
ALLOWS THE CONTACTS TO OPEN REGARDLESS Of THE STATE OF THE
MECHANISM, THAT IS THE BREAKER MECHANISM
IS "TRIP-FREE".
HIGH SPEED BREAKER CLOSING OPERATION IS ACHIEVED
THROUGH THE RELEASE OF A PRE-CHARGED (STORED ENERGY TYPE)
CLOSING SPRING, WHILE THE COMPRESSED MAIN MOVING CONTACT
SPRINGS AND THE CLOSING SHAFT TORSION SPRING PROVIDE THE
ENERGY FOR THE HIGH SPEED CONTACT SEPARATION AND OPENING
OF THE BREAKER.
BREAKERS ARE PROVIDED WITH EITHER A MANUALLY
OPERATED HANDLE OR AN ELECTRIC MOTOR FOR COMPRESSING THE
CLOSING SPRING.
2. THE CONDUCTIVE MEMBERS ARE ASSEMBLED ON A
MOULDED BASE OF FIBERGLASS-REINFORCED POLYESTER.
INDIVIDUAL POLE PIECES CAREFULLY INTERLOCKED TOGETHER AND
SUPPORTED BY A STEEL FRAME PROVIDE THE MECHANICAL
SUPPORT AND INSULATING STRUCTURE REQUIRED. THE CONDUCTIVE
MEMBERS COMPRISE THE MAIN POWER TERMINALS OR DRAWOUT
CONTACTS, THE MAIN FIXED CONTACTS AND THE MAIN MOVING
CONTACTS.
3. THE INTERRUPTING DEVICES ARE THE FIXED AND MOVING
ARCING CONTACTS AND THE ARC CHUTES.
IN ADDITION TO THESE MAIN FUNCTIONAL COMPONENTS THE
BREAKER IS AVAILABLE WITH OVERLOAD PROTECTION AND OTHER
ACCESSORIES AND INTERLOCKING DEVICES.
2. RECEIVING - HANDLING - STORAGE - INSTALLATION
2.1 RECEIVING
IMMEDIATELY UPON RECEIPT OF THE BREAKER AN
EXAMINATION SHOULD BE MADE FOR DAMAGE SUSTAINED IN
TRANSIT. IF DAMAGE HAS OCCURRED OR THERE IS EVIDENCE OF
ROUGH HANDLING, A CLAIM SHOULD BE FILED IMMEDIATELY WITH
THE TRANSPORTATION COMPANY AND SCHNEIDER ELECTRIC
SHOULD BE NOTIFIED. CHECK ALL PARTS AGAINST THE PACKING LIST
TO MAKE SURE ALL THE CORRECT ITEMS HAVE BEEN RECEIVED.
2.2 HANDLING
LIFT THE BREAKER BY THE STEEL CHANNELS AT THE FRONT
AND BACK. DO NOT LIFT BY THE CONNECTING TERMINALS, ARC
CHUTES, OR OPERATING HANDLE. SPECIAL LIFTING DEVICES ARE
AVAILABLE FOR USE WITH OVERHEAD CRANE OR SIMILAR MEANS
(SEE SECTION 9. 1 ). CHECK THE UNIT THOROUGHLY TO SEE THAT NO
PARTS WERE DAMAGED OR FORCED OUT OF ALIGNMENT DURING
SHIPMENT. IF REPLACEMENT PARTS ARE REQUIRED, THE MANU-
FACTURER SHOULD BE NOTIFIED PROMPTLY. THE BREAKER SHOULD
BE INSTALLED IN A CLEAN DRY VENTILATED AREA WHICH IS FREE
FROM ATMOSPHERIC CONTAMINANTS.
2.3 STORAGE
EACH CIRCUIT BREAKER SHOULD BE STORED IN ITS SHIPPING
CONTAINER IN ANUPRIGHT POSITION IN A CLEAN DRY AREA. SHOULD
THE UNIT GET WET, IT MUST BE THOROUGHLY DRIED OUT USING
FORCED WARM AIR OVER AN EXTENDED PERIOD UNTIL "INFINITE"
READINGS ARE OBTAINED USING A 600 VOLT MEGGER.
2.4 MOUNTING
H-3 AND HL-3 CIRCUIT BREAKERS SHOULD BE MOUNTED IN
SHEET STEEL ENCLOSURES IN ACCORDANCE WITH RECOMMENDED
DIMENSIONS. THE MOUNTING SUPPORT SHOULD BE A RIGID
STRUCTURE ABLE TO WITHSTAND THE IMPACT CAUSED BY THE
SWITCHING OPERATIONS, WITHOUT ANY DISTORTION AND UNDUE
VIBRATION OF THE MECHANISM. ALL H-3 AND HL-3 ENCLOSURES,
WITH THE EXCEPTION Of THE 6000A 1OOH-3, REQUIRE AN INSULATING
BARRIER MADE Of 1/16 INCH THICK NEMA GRADE GPO-3 MATERIAL
INSTALLED ON THE INSIDE TOP SURFACE USING NON-METALLIC
HARDWARE. NOTE THAT THE WIDER BARRIERS MAY REQUIRE
ADDITIONAL HARDWARE TO SUPPORT THE OUTER EDGES.
FIG. 2.4 ENCLOSURE INSULATING
ENCL.
WIDTH
BARRIER
WIDTH
MOUNTING
HOLES
"A" "B" "C"
18 16 8 3/4
25 17 5/8 15 3/4
30 22 5/8 15 3/4
32 31 15 3/4
36 34 15 3/4
38 37 15 3/4
45 44 15 3/4
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FIG. 2.6 CRADLE WIRING
2.5 POWER TERMINAL CONNECTIONS
THEH-3 POWER TERMINALS ARE PLATED FOR MAXIMUM JOINT
EFFICIENCY AND CABLE OR BUS CONNECTORS MUST BE CLEAN AND
FREE FROM DENTS OR BURRS, AND BOLTED SECURELY TO THE
TERMINALS. POOR JOINTS LEAD TO OVERHEATING, SUBSEOUENT
CONTACT DETERIORATION, AND AN EVENTUAL FAILURE.
CONNECTIONS SHOULD BE PROPERLY SUPPORTED SO AS NOT TO
TRANSFER ANY UNNECESSARY MECHANICAL OR SHORT CIRCUIT
STRESSES TO THE TERMINALS. ANY
STRAIN WHICH MAY HAVE NO APPARENT EFFECT INITIALLY MAY
AFTER PROLONGED PERIODS OF VIBRATION AND SHOCK FROM
NORMAL OPERATION, CAUSE POOR CONTACT ALIGNMENT.
2.6 SECONDARY CONTROL CIRCUITS
CONTROL CIRCUIT WIRING, WHERE APPLICABLE, SHOULD BE
MADE IN STRICT ACCORDANCE WITH DETAILED WIRING DIAGRAMS.
FIXED MOUNTED BREAKERS ARE PROVIDED WITH TERMINAL BLOCKS
FOR CONNECTIONS TO REMOTELY LOCATED CONTROL AND
INDICATING DEVICES. REMOTE WIRING SHOULD BE BUNDLED
TOGETHER, PROPERLY SUPPORTED AWAY FROM PRIMARY
CONNECTIONS.
CONTROL WIRING FROM CRADLE MOUNTED SECONDARY
CONTACTS OF DRAWOUT TYPE BREAKERS MUST BE PASSED THROUGH
THE HOLES PROVIDED IN THE CRADLE BACKPAN AND SECURED ON
THE INSIDE IN SUCH A MANNER THAT IT IS KEPT AWAY FROM THE
PATH OF THE BREAKER MAIN DRAWOUT CONTACTS AND SHUTTERS IF
PROVIDED.
METER SHUNTS, RESISTORS AND SIMILAR DEVICES THAT
OPERATE AT RELATIVELY HIGH TEMPERATURE SHOULD BE MOUNTED
AWAY FROM THE CIRCUIT BREAKER SO THEY DO NOT CONTRIBUTE
TO THE HEATING OF THE UNIT.
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1. ARC CHUTE ASSEMBLY 2. INTERPHASE BARRIER 3. R.H. END BARRIER 4. L.H. END BARRIER 5. FRONT FLASH SHIELD 6. CLOSED-OPEN LINK 7. CRANK ASSEMBLY 8. CRANK BOX 9. CRANK Box BEARINGS
10. HOLDING PAWL 11. RACHET WHEEL 12. OSCILLATING LEVER 13. CLUTCH 14. CHARGED-DISCHARGED LINK 15. CLOSED-OPEN INDICATOR 16. CHARGED-DISCHARGED INDICATOR 17. FRONT PLATE 18. INDICATOR PLATE 19. FACEPLATE Box ASSEMBLY 20. FLOATING TRIM 21. FACEPLATE ASSEMBLY 22. HANDLE ASSEMBLY 23. CLOSING LATCH
48. WAFER CONTACT SPRING 49. SPRING HOLDER 50. MOVING ARCING CONTACT 51. STATIONARY ARCING CONTACT 52. LOAD TERMINAL 53. ANTI-BOUNCE PLATE 54. BASE MOULDING 55. TRIP FLIPPER 56. TRIP COIL ASSEMBLY 57. LOWER CHANNEL 58. FINGER SPACER 59. DRAWOUT CONTACT ASSEMBLY 60. SLS CAM 61. GROUND CONTACT 62. LOWER FLASH SHIELD 63. SECONDARY DRAWOUT CONTACT (MOVING)
24. CLOSE LEVER 25.TRIP ROD ASSEMBLY 26.SPRING GUIDE PIN 27. CLOSING CASTING 28. TOGGLE PIN 29. TIE ROD ASSEMBLY 30. CLOSING SHAFT 31. MAIN SPRING 32. GUIDE BUSHINGS 33. CLAMP ASSEMBLY 34. BREAKER FRAME 35. TRIP SHAFT 36. TRIP LATCH 37. LATCH BEARING 38. LOWER MOULDING 39. SENSOR MOUNTING BRACKET 40. BARRIER 41. SENSOR 42.JUMPER 43.CENTER STATIONARY MAIN CONTACT 44.MAIN MOVING CONTACT (WAFER ASSY) 45.UPPER MOVING MAIN CONTACT 46.CLOSING LINK ASSEMBLY
47.BRAID
3. BREAKER COMPONENTS AND CONTROLS 3.1 BREAKER SECTIONAL VIEW
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1. FLOATING TRIM
2. FACEPLATE 11. GATE FOR DRAWOUT CRANK (DRAWOUT MOUNTED UNITS ONLY)
3. CONTACT POSITION INDICATOR 12. MANUAL TRIP
4. MAIN SPRING CHARGED/DISCHARGED INDICATOR 13. SENSOR TAP SETTING INDICATOR
5. MANUAL CHARGING HANDLE (M.O. UNITS ONLY) 14. SERIAL NUMBER
6. OPENING FOR EMERGENCY CHARGING HANDLE (E.O. UNITS ONLY) 15. OVERLOAD LOCKOUT RESET (OPTIONAL)
7. OPERATIONS COUNTER (OPTIONAL) 16. BLOWN FUSE INDICATOR AND RESET (TYPE HL-3 UNITS ONLY)
8. MANUAL CLOSE (M.O. UNITS ONLY) 17. ELECTRICAL CLOSE (E.O. UNITS ONLY)
9. APERTURE FOR EMERGENCY MANUAL CLOSE (E.O. UNITS ONLY) 18. ELECTRICAL TRIP (E.O. UNITS ONLY)
10. FACEPLATE KEY INTERLOCK (OPTIONAL) 19. CHARGING MOTOR CUT-OFF SWITCH
3.2 CRADLE SECTIONAL VIEW
3.3 BREAKER FACEPLATE AND CONTROLS
FIG. 3.3.1 FACEPLATE FOR MANUALLY OPERATED (M.O.) UNIT FIG. 3.3.2 FACEPLATE FOR ELECTRICALLY OPERATED (E.O.) UNIT
1. DRAWOUT RAILS (FOLDED UP)
2. BACKPAN
3. MAIN POWER STABS
4. MAIN POWER TERMINALS
5. MAIN TERMINAL MOULDINGS
6. SECONDARY DRAWOUT
CONTACTS (FIXED)
7. GROUND STAB
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FIG 4.1.2 TEST POSITION
- DRAWOUT MECHANISM IS ENGAGED, BREAKER IS
MECHANICALLY SECURED IN CRADLE
- GROUND CONTACTS ENGAGED
- "TEST POSITON" SECONDARY CONTACTS ENGAGED
FIG. 4.1.1 DISCONNECTED POSITON
- THE CRADLE/BREAKER DRAWOUT MECHANISM IS DISENGAGED
- ALL CONTACTS ARE DISENGAGED
4.1 DRAWOUTMECHANISM - BREAKER INSERTION AND REMOVAL
THE THREE POSITIONS OF A DRAWOUT MOUNTED
BREAKER ARE SHOWN BELOW.
FIG. 4.1.3 OPERATING POSITION
- BREAKER FULLY DRAWN INTO CRADLE
- GROUND CONTACT ENGAGED
- "OPERATING POSITION" SECONDARY CONTACTS ENGAGED
- MAIN POWER CONTACTS ENGAGED.
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FIG. 4.1.4 DRAWOUT MECHANISM
1. GATE
2. CRANK SOCKET
3. DRAWOUT LEVER BUSHINGS
4. CRADLE DRAWOUT SLOTS
TO OPERATE THE DRAWOUT MECHANISM, THE GATE 1S
LOWERED TO EXPOSE THE CRANK SOCKET, AND THE DRAWOUT
CRANK INSERTED. THE GATE IS INTERLOCKED TO BOTH THE
CHARGING AND TRIPPING MECHANISMS OF THE BREAKER, SUCH
THAT IF THE MAIN SPRING IS CHARGED, IT WILL BE DISCHARGED AND
IF THE CONTACTS ARE CLOSED, THE BREAKER WILL BE TRIPPED. AS
LONG AS THE GATE IS DOWN, THE CONTACTS CANNOT BE CLOSED.
AN ADDITIONAL INTERLOCKING MECHANISM WILL NOT ALLOW THE
GATE TO BE RAISED IF THE BREAKER IS PART WAY BETWEEN TEST
AND OPERATION POSITIONS.
THIS WAY THE MAIN SPRING WILL ALWAYS BE
DISCHARGED AND THE CONTACTS OPEN WHEN THE BREAKER IS
BEING DRAWN IN OR OUT OR WHEN IT IS LEFT BETWEEN TEST AND
OPERATING POSITION.
NOTE THAT LOWERING THE GATE WITH THE MAIN SPRING
CHARGED, OR MANUALLY CHARGING THE SPRING WITH THE GATE
LOWERED, WILL RESULT IN A "DRY RUN", THAT IS, THE SPRING
DISCHARGES WITHOUT CLOSING THE CONTACTS. THIS
IS A SAFETY FEATURE AND DRY RUNS DURING DRAWOUT OPERATION
MAY SOMETIMES BE UNAVOIDABLE, BUT BECAUSE THEY STRESS THE
MECHANISM TO A GREATER EXTENT THAN NORMAL OPERATIONS,
DRY RUNS SHOULD BE AVOIDED IF POSSIBLE.
REFER TO SECTION 4.8.
TO INSTALL A BREAKER PROCEED AS FOLLOWS:
-OPEN THE CUBICLE DOOR AND FOLD DOWN THE RAILS
-PLACE BREAKER ON THE RAILS AND ROLL IT INTO THE CRADLE
-FOLD THE RAILS UP AND FULLY CLOSE THE DOOR
-INSERT THE DRAWOUT CRANK AND TURN CLOCKWISE UNTIL
THE BREAKER IS IN THE TEST POSITION AS SHOWN IN FIG. 4.1.2 OR IN
THE OPERATING POSITION AS SHOWN IN FIG. 4.1.3 AND REMOVE THE
CRANK. WHEN CRANKING THE BREAKER INTO THE OPERATING
POSITION, CONTINUE CRANKING UNTIL THE MECHANISM COMES TO A
FIRM STOP.
TO REMOVE A BREAKER, THE PROCEDURE IS JUST THE
OPPOSITE TO THE ABOVE. BEFORE INSERTING THE DRAWOUT
CRANK, REFER TO SECTION 4.8 TO AVOID UNNECESSARY DRY RUNS.
FOR DRAWOUT GATE ADJUSTMENT REFER TO SECTION 8.4.
4.2 GROUNDING CONTACT
GROUNDING CONTINUITY IS ESTABLISHED 1/8" (3.2mm) BEFORE
SECONDARY CONTROL CONTACTS ARE ENGAGED IN THE "TEST"
POSITION. IT IS MAINTAINED THROUGHOUT BREAKER POSITIONING IN
THE ENCLOSURE UNTIL THE SECONDARY CONTROL CONTACTS HAVE
BEEN SEPARATED AGAIN BY THE SAME DIMENSION. GROUNDING
CONTINUITY IS ESTABLISHED WHEN THE MOVING GROUND CONTACT
ON THE BREAKER (FIG. 3.1 ITEM 61) MATES WITH THE STATIONARY
GROUND STAB LOCATED ON THE CRADLE (FIG. 3.2 ITEM 7).
4.3 SECONDARY CONTROL CONTACTS
SECONDARY CONTROL CONTACTS AUTOMATICALLY CONNECT
OR DISCONNECT CONTROL CIRCUITS AS THE BREAKER MOVES
THROUGH ITS DRAWOUT POSITIONS. A TOTAL of 40 CONTACTS CAN BE
PROVIDED ON 14" WIDE BREAKERS (MAXIMUM 1600 AMPS) AND 21"
WIDE BREAKERS EQUIPPED WITH MECHANICAL INTERLOCK
(MAXIMUM 2000 Amps). ALL OTHER BREAKERS CAN BE PROVIDED WITH
48 CONTACTS. EACH CONTACT HAS A CONTINUOUS CURRENT RATING
OF 30 AMPS. IN APPLICATIONS WHERE A CONTROL VOLTAGE SUPPLY IN
EXCESS OF 250V IS TO BE USED, THE SECONDARY CONTACTS ARE
DOUBLE-SPACED, (I.E. ADJACENT CONTACTS ARE OMITTED).
THE FIXED (CRADLE MOUNTED) CONTACT ASSEMBLIES MAY
BE SUPPLIED WITH ELECTRICALLY SEPARATED OR JUMPERED "TEST" AND
"OPERATING" POSITION CONTACTS TO PROVIDE A VARIETY OF
OPTIONAL CONTROL FUNCTIONS, IE. ISOLATION, BYPASS, ETC.
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4.4 BREAKER CLOSING
BEFORE ATTEMPTING TO CLOSE A BREAKER, MAKE SURE ALL
ELECTRICAL AND MECHANICAL CLOSING INTERLOCKS ARE IN THE
RESET POSITION. (REFER To 4.8 "MECHANICAL CLOSING INTERLOCKS").
FIG. 4.4.2 ELECTRICALLY OPERATED CLOSING MECHANISM
1. HOLDING PAWL
2. RATCHET WHEEL
3. BEARING IN RATCHET WHEEL
4. CLUTCH
5. CLOSE LATCH
6. OSCILLATING LEVER
7. DRIVING PAWL
8. CLOSE COIL
9. SPRING CHARGING MOTOR
10. SPRING LIMIT SWITCH
11. SPRING LIMIT SWITCH LEVER
12. MAIN SPRING
13. AUXILIARY SWITCH
14. CLOSE COIL LIMIT SWITCH
FIG. 4.4.1 MANUALLY OPERATED CLOSING MECHANISM
FIG. 4.3 SECONDARY CONTROL CONTACTS.
1. MOVING (BREAKER MOUNTED) SECONDARY
CONTACT ASSEMBLY
2. FIXED (CRADLE MOUNTED) SECONDARY
CONTACT ASSEMBLY
3. SEPARATE "TEST POSITION" CONTACT
4. SEPARATE "OPERATING, POSITION" CONTACT
5. "TEST" AND "OPERATING" CONTACTS WITH JUMPER.
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4.7 MFCHANICAL CLOSING INTERLOCKS AND PADLOCKING
BREAKERS MAY BE EQUIPPED WITH MECHANICAL DEVICES
WHICH TRIP THE BREAKER AND PREVENT THE CONTACTS FROM
BEING RECLOSED UNTIL THESE DEVICES HAVE BEEN RESET. SUCH
DEVICES ACT ON THE TRIP SHAFT OF THE BREAKER, HOLDING IT IN
THE TRIPPED POSITION. IF THE MAIN SPRING IS CHARGED AND
RELEASED, A DRY RUN WILL OCCUR BUT THE CONTACTS WILL NOT
CLOSE. THE FOLLOWING OPTIONAL DEVICES SERVE THIS FUNCTION.
THE ACTON REQUIRED TO RESET THEM IS ALSO INDICATED.
•UNDERVOLTAGE TRIP (REF. SECTION 5.3)
-RESETS AUTOMATICALLY WHEN CONTROL POWER IS APPLIED.
•OVERLOAD LOCKOUT (REF. SECTION 5.5)
-PUSH THE MANUAL RESET BUTTON ON FACEPLATE TO RESET
•DOOR INTERLOCK (REF. SECTION 5.6)
-RESETS WHEN COMPARTMENT DOOR IS CLOSED
•KEY INTERLOCKS (REF. SECTION 5.7)
-RESETS WHEN KEY IS INSERTED AND TURNED
(KEY WILL BE TRAPPED IN THIS POSITION)
•MECHANICAL INTERLOCKS (REF. SECTION 5.8)
-RESETS AUTOMATICALLY WHEN ALTERNATE BREAKER IS
OPENED
•ANTI-SINGLE-PHASE DEVICE AND BLOWN FUSE INDICATOR
(REF. SECTION 4.1 1 )
-RESETS BY PUSHING INDICATORS UP AND IN TO THE LOCKED
POSITION
IN ADDITION TO THESE DEVICES, THE MANUAL TRIP BUTTON
AND DRAWOUT MECHANISM GATE ARE EQUIPPED WITH PROVISIONS
FOR PADLOCKING FOR THE PURPOSE OF LOCKING BREAKER IN OPEN
POSITION OR TO PREVENT OPERATION OF DRAWOUT MECHANISM.
THE SAFESTMETHOD TO PREVENT ACCIDENTAL BREAKER CLOSING
AND ENERGIZATION OF A BUS OR FEEDER WHICH MUST REMAIN DE-
ENERGIZED, IS TO WITHDRAW BREAKER FROM "OPERATING"
POSITION AND TO SECURE A PADLOCK THROUGH THE DRAWOUT
MECHANISM GATE PADLOCKING HASP.
FOR BREAKERS LEFT IN "OPERATING" POSITION, ACCIDENTAL
BREAKER CLOSING CAN BE PREVENTED BY LEAVING BREAKER WITH
CLOSING SPRING DISCHARGED AND ENSURING THAT IT REMAINS DIS-
CHARGED.
ELECTRICALLY OPERATED BREAKERS CAN BE PREVENTED
FROM CHARGING BY TURNING OFF MOTOR CUTOFF SWITCH, OR BY
REMOVING CONTROL POWER FUSE AND BY KEEPING THE
EMERGENCY CHARGING HANDLE REMOVED.
MANUALLY OPERATED BREAKERS WITH THE NON-REMOVABLE
CHARGING HANDLE HAVEHANDLE PADLOCKING PROVISION. ALOCK
SECURED THROUGH HANDLE HASP PREVENTS ENGAGEMENT WITH
RATCHET WHEEL CLUTCH.
IN ADDITION A PADLOCK THROUGH THE MANUAL TRIP
BUTTON AND HASP WITH THE BUTTON DEPRESSED WILL PROVIDE
FURTHER ASSURANCE THE MANUALLY OR ELECTRICALLY OPERATED
BREAKER REMAINS OPEN.
4.5CLOSING MANUALLY OPERATED BREAKER
TO CHARGE THE MAIN SPRING, ROTATE THE CHARGING HANDLE
COUNTER CLOCKWISE TO THE UPRIGHT POSITION AND PUSH IN TO
ENGAGE THE HANDLE WITH THE RATCHET WHEEL CLUTCH. ON
FRAME SIZES 1600 AMPS AND ABOVE, THE HANDLE IS A PULLOUT
EXTENSION TYPE FOR EASE OF OPERATION.
ROTATE THE HANDLE CLOCKWISE 180 DEGREES TO FULLY
CHARGE THE SPRING. A MULTI-TOOTH RATCHET WHEEL AND HOLDING
PAWL PREVENT RECOIL AND PERMIT SPRING CHARGING TO BE
PERFORMED IN SEVERAL SHORT STROKES IF DESIRED.
AS THE RATCHET WHEEL ROTATES THE INTERNAL CRANK TO A
POSITION 13 DEGREES PAST TOP-DEAD-CENTRE, THE CHARGING
STROKE IS STOPPED. A BEARING WITHIN THE RATCHET WHEEL COMES
TO RESET AGAIN THE CLOSE LATCH AND THE FORCE OF THE
COMPRESSED MAIN SPRING IS HELD BY THE LATCH IN READINESS TO
CLOSE.
OPERATION OF THE CLOSE LATCH BY PUSHING THE MANUAL
CLOSE BUTTON (FIG. 3.3.1, ITEM 8) IN THE FACEPLATE, RELEASES THE
SPRING ENERGY TO CLOSE THE BREAKER.
ONLY A RAPID TRIP-RECLOSE OPERATION IS REQUIRED
SHOULD THE SPRING BE RECHARCED AT THIS TIME. THIS WILL
AVOID UNNECESSARY DRY RUNS WHEN OPERATING THE
DRAWOUT MECHANISM.
4.6CLOSING ELECTRICALLY OPERATED BREAKER
THE ELECTRICALLY OPERATED BREAKER IS EQUIPPED WITH
CHARGING MOTOR TO CHARGE THE MAIN SPRING AND A CLOSING
COIL TO RELEASE THE CLOSE LATCH.
BEGIN BY PLACING THE MOTOR ISOLATING SWITCH (FIG. 3.3.2
ITEM. 19) TO THE "ON" POSITION. THE MOTOR OPERATED OSCILLATING
LEVER WILL ROTATE THE RATCHET WHEEL UNTIL THE MAIN SPRING
IS FULLY CHARGED. AT THIS POINT A CAM BEHIND THE CRANKBOX
OPERATES THE SPRING LIMIT SWITCH LEVER AND THE SPRING LIMIT
SWITCH CUTS OFF THE MOTOR. ROTATION IS STOPPED AND THE
RATCHET WHEEL IS HELD IN POSITION BY THE CLOSE LATCH.
PUSHING THE "CLOSE" BUTTON ON THE FACEPLATE (FIG..3.3.2, ITEM 17)
ENERGIZES THE CLOSE COIL WHICH RELEASES THE CLOSE LATCH. THE
MAIN SPRING DISCHARGES AND THE MAIN CONTACTS CLOSE.
DEPENDING ON CONTROL REQUIREMENTS, INTERNAL BREAKER
WIRING WILL PROVIDE FOR EITHER CHARGE AFTER CLOSING
OR CHARGE AFTER OPENING OPERATION. (REFER To 4.18).
A REMOVABLE HANDLE IS PROVIDED TO PERMIT
EMERGENCY MANUAL CHARGING OF THE SPRING. A MECHANICAL
CLOSE BUTTON LIKE THAT ON THE MANUALLY OPERATED UNIT IS NOT
INCLUDED. EMERGENCY OPERATION OF THE CLOSE LATCH IS
ACCOMPLISHED BY INSERTION Of A PIN ATTACHED TO THE UPPER
END OF THE EMERGENCY CHARGING HANDLE, THROUGH A SMALL
APERTURE IN THE FACE PLATE (FIG. 3.3.2, ITEM. 1 7). PUSH THE PIN
GENTLY THROUGH THE APERTURE UNTIL THE BREAKER CLOSES.
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4.8BREAKER OPENING
THE BREAKER CAN BE OPENED BY PRESSING THE MANUAL TRIP
BUTTON WHICH OPERATES DIRECTLY ON THE TRIP SHAFT OF THE BREAKER OR BY PRESSING THE ELECTRICAL TRIP BUTTON (ON ELECTRICALLY OPERATED UNITS) WHICH ACTIVATES THE TRIP COIL.
ALL METHODS OF TRIPPING FUNCTION BY ROTATING THE
BREAKER TRIP SHAFT. THE TRIP LATCH, ATTACHED TO THE SHAFT IS ROTATED TOWARD THE REAR OF THE BREAKER, FREEING THE TRIP LATCH BEARING. THIS ALLOWS THE UPPER PORTION OF THE CLOSING MECHANISM LINKAGE TO COLLAPSE AND THE ENERGY STORED IN THE MOVING CONTACT SPRINGS AND THE CLOSING SHAFT TORSION SPRING RAPIDLY OPENS THE CONTACTS.
OTHER DEVICES WHICH OPERATE TO OPEN THE BREAKER ARE
SHUNT TRIP COILS FOR REMOTE OR OVERCURRENT PROTECTION TRIPPING, UNDERVOLTAGE TRIP, DOOR INTERLOCK, FACEPLATE OR CELL KEY INTERLOCKS AND THE ANTI-SINGLE PHASE DEVICE. FIG. 4.8 BREAKER OPENING
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4.9REJECTION FEATURE
A REJECTION FEATURE IS PROVIDED ON ALL BREAKERS. IT
PREVENTS ENTRY OF A BREAKER INTO A CRADLE Of THE SAME WIDTH
BUT DIFFERENT RATING. PINS ON BOTH SIDES OF THE BREAKER
FRAME MATCH SLOTS IN BRACKETS MOUNTED ON BOTH SIDES Of THE
CRADLE. IF THE CRADLE IS A DIFFERENT RATING THAN
THE BREAKER, THE BREAKER PINS WILL NOT MATCH THE SLOTS AND
ENTRY OF THE BREAKER IS PREVENTED.
FIG. 4.9 REJECTION FEATURE
1. BREAKER REJECTION PIN
2. CRADLE REJECTION BRACKET
4.1O CLOSING SPRING DISCHARGE AND DRY RUNS
DISCHARGING THEMAIN SPRING WITHOUT CLOSING THE
MAIN CONTACTS IS REFERRED TO AS A DRY RUN. THIS TYPE OF
OPERATION CREATES MUCH MORE STRESS IN THE BREAKER
MECHANISM THAN NORMAL CLOSING OPERATIONS AND
SHOULD BE AVOIDED IF POSSIBLE.
TO LIMIT THE NUMBER Of DRY RUNS, THE FOLLOWING
METHOD Of SPRING DISCHARGE SHOULD ALWAYS BE USED
WHEN BREAKER IS IN "TEST" OR "DISCONNECTED" POSITION OR
WHEN REMOVED FROM CRADLE. IT SHOULD .ALSO BE USED
WHEN IN "OPERATING" POSITION IF POSSIBLE:
1. IF BREAKER IS ELECTRICALLY OPERATED, TURN OFF MOTOR
ISOLATING SWITCH.
2. IF BREAKER IS OPEN AND MAIN SPRING CHARGED: CLOSE - THEN
TRIP BREAKER.
3. If BREAKER IS CLOSED: TRIP BREAKER BY USING
ELECTRICAL OR MECHANICAL TRIP BUTTONS ON
FACEPLATE (DO NOT USE THE DRAWOUT MECHANISM
GATE). IF THE MAIN SPRING IS CHARGED, RECLOSE, THEN
TRIP BREAKER.
FIG. 4.1 1 OVERCURRENT PROTECTION
I . USD RELAY
2. CURRENT SENSOR
3. TRIP COIL
4. CURRENT SENSOR TAP INDICATION
4.11FAULT PROTECTION
TYPE H-3 AND HL-3 BREAKERS ARE SUPPLIED WITH THE TYPE
USD SOLID STATE OVERCURRENT RELAY AS A STANDARD FEATURE.
THE USD RELAY PROTECTS LOW VOLTAGE POWER SYSTEMS
AGAINST DAMAGE CAUSED BY SHORT CIRCUITS, OVERLOADS AND
GROUND FAULTS. THE RELAY MAY HAVE UP TO FOUR PICK UP
ELEMENTS: INSTANTANEOUS, SHORT-TIME, LONG-TIME AND
GROUND FAULT. LOCAL AND REMOTE INDICATION ARE
AVAILABLE. IN ADDITION, ZSIP(R) (ZONE SELECTIVE
INSTANTANEOUS PROTECTION) IS AVAILABLE FOR THE SHORT-
TIME AND GROUND FAULT ELEMENTS.
TRIPPING ENERGY FOR THE OPERATION OF THE RELAY IS
OBTAINED SOLELY FROM THE CIRCUIT BEING PROTECTED.
THREE MULTIPLE-TAP CURRENT SENSORS, MOUNTED ON
THE BREAKER PROVIDE THE INPUT TO THE USD RELAY FROM THE
PROTECTED CIRCUIT. A FOURTH SENSOR, CAN ALSO BE USED WHERE
FOUR-WIRE GROUND FAULT PROTECTION IS REQUIRED. AN
ADJUSTABLE SENSOR TAP SETTING INDICATOR is PROVIDED ON THE
BREAKER FACEPLATE (SEE SECTION 8.10).
A DEDICATED DIRECT ACTING SOLENOID TYPE TRIP COIL
PROVIDES POSITIVE ACTIVATION OF THE TRIP LATCH ON THE
BREAKER, AND POSITIVE RESETTING AFTER OPERATION.
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4.13 ANTI-SINGLE-PHASE DEVICE AND BLOWN FUSE INDICATOR
AN ANTI-SINGLE-PHASE DEVICE AND BLOWN FUSE INDICATOR IS
SUPPLIED ON ALL HL-3 -BREAKERS. IT CONSISTS Of THREE
SOLENOIDS, ONE WIRED IN PARALLEL WITH EACH FUSE. DURING
NORMAL OPERATION, THE SOLENOID IS SHORTED OUT BY THE FUSE
ITSELF. WHEN A FUSE BLOWS, HOWEVER, LINE VOLTAGE IS THEN
PRESENT ACROSS THE SOLENOID AND IT IS ACTIVATED. THE
SOLENOID PLUNGER PUSHES A COLOUR CODED SLIDER FORWARD. THE
REAR OF THE SLIDER OPERATES THE BREAKER TRIP SHAFT, TRIPPING
THE BREAKER, WHILE THE FRONT END Of THE SLIDER PROTRUDES
THROUGH THE FACEPLATE PROVIDING AN INDICATION OF WHICH
FUSE BLEW. THE SLIDERS ARE COLOUR CODED RED, YELLOW AND
BLUE FOR LEFT, CENTER AND RIGHT PHASES. THE BREAKER WILL BE
HELD TRIP-FREE UNTIL THE PROTRUDINGSLIDER(S) HAVE BEEN
RESET. THIS IS ACCOMPLISHED BY LIFTING AND PUSHING ON THE
END OF THE SLIDER.
IF THE SLIDER IS RESET BUT THE BLOWN IS NOT REPLACED, THE
BREAKER CAN BE RECLOSED, BUT IT WILL BE TRIPPED IMMEDIATELY.
NOTE THAT IF THE MAIN POWER FUSES ARE BEING CHECKED
FOR CONTINUITY WHILE IN THE BREAKER, THE CONTROL FUSES IN
THE ANTI-SINGLE- PHASE CIRCUIT MUST BE REMOVED, OTHERWISE A
BLOWN POWER FUSE WOULD STILL INDICATE CONTINUITY THROUGH
THE SOLENOID.
NOTE:THIS DEVICE ONLY PROVIDES ANTI-SINGLE-PHASE
PROTECTION FROM A BLOWN FUSE SITUATION. IT DOES NOT
PROTECT AGAINST SINGLE- PHASE CONDITIONS FROM THE SOURCE.
4.12 FUSE MOUNTING
ALL HL-3 CIRCUIT BREAKERS IN FRAME SIZES UP TO AND
INCLUDING 4000 AMPS HAVE PROVISION FOR MOUNTING NEMA CLASS
L HRC FUSES, MOUNTED ON THE LINE SIDE ON A FRAME EXTENSION
AT THE REAR OF THE UNIT. IN THE 6000A RATING, A SEPARATE FUSE
TRUCK IS AVAILABLE.
IN ALL CASES BUT THE 6000A FRAME, FUSES WITH A HIGHER
RATING THAN THE BREAKER FRAME SIZE CAN BE INSTALLED AND
STILL MAINTAIN PROPER COORDINATION BETWEEN THE CONTACT
AND FUSE INTERRUPTING CAPABILITIES. THE MAXIMUM FUSE
RATINGS ARE AS FOLLOW :
FIGURE 4.12 FUSE MOUNTING
FIG. 4.13 ANTI-SINCLE-PHASE DEVCE
1. SOLENOID
2. SLIDER
3. BLOWN FUSE INDCATOR
4. TRIP SHAFT LEVER
HL-3 FRAME
(AMPERES) RELAY RATING (AMPERES) MAXIMUM
FUSE
(AMPERES)
600 600 1600 NEMA L
800 800 1600 NE,MA L
1600 1600 3000 NEMA L
2000 2000 3000 NEMA L
3000 3000 4000 NEMA L
4000 4000 5000 NEMA L
6000 6000 6000 NEMA L
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4.14 SHUNT TRIP COIL
THERE MAY BE TWO SHUNT TRIP COILS INSTALLED ON A
BREAKER. BREAKERS EQUIPPED WITH A USD RELAY ARE FITTED WITH
A SHUNT TRIP COIL OPERATED EXCLUSIVELY BY THE RELAY. THIS
DEVICE IS A CYLINDRICAL SOLENOID MOUNTED BELOW THE TRIP
SHAFT BETWEEN THE LEFT AND RIGHT HAND MECHANISM
SIDEPLATES. THE SECOND, SHUNT TRIP -COIL IF NEEDED FOR
COMMON TRIPPING REOUIREMENTS IS MOUNTED ON THE OUTSIDE OF
THE LEFT HAND MECHANISM SIDE PLATE. IF A BREAKER IS EQUIPPED
WITH UNDERVOLTAGE TRIP DEVICE (NV) AS WELL AS SHUNT TRIP
COIL,THE "NV" OCCUPIES THE SHUNT TRIP COIL LOCATION WHILE THE
SHUNT TRIP COIL IS MOUNTED ON THE LOWER CROSS CHANNEL TO
THE LEFT OF THE "NV". EACH SHUNT TRIP COIL ACTS VERTICALLY ON
ITS OWN TRIP SHAFT LEVER. BECAUSE THE COILS ARE NOT
CONTINUOUSLY RATED, A NORMALLY OPEN AUXILIARY SWITCH
CONTACT IS WIRED IN SERIES WITH THE COIL TO OPEN THE TRIP
CIRCUIT WHEN THE BREAKER IS OPEN. AC OR DC POWERED COILS
WILL OPERATE TO TRIP AT APPROXIMATELY 50% OF RATED VOLTAGE.
THE NUMBER OF CONTACTS REOUIRED FOR VARIOUS INTERNAL
BREAKER CONTROL SCHEMES.
THE FOLLOWING CONTACT RATINGS APPLY:
10 AMPERES UP TO 254V A.C.
1 AMPERE AT 250V D.C.
2 AMPERES AT 125V D.C.
DUE TO SPACE LIMITATIONS, A DIFFERENT MODEL is USED FOR
20 POLE AUXILIARY SWITCHES, AND 12 POLE SWITCHES ON 14"
WIDE BREAKER. THESE SWITCHES ARE NOT RATED FOR D.C.
SWITCHING FUNCTIONS.
NORMALLY OPEN AUXILIARY SWITCH CONTACTS ARE IDENTIFIED
BY THE SYMBOL "a" ON THE WIRING DIAGRAM, NORMALLY CLOSED BY
4.1 6 CLOSING COIL (CC)
THIS DEVICE IS SUPPLIED ON ELECTRICALLY OPERATED CIRCUIT
BREAKERS AND CONSISTS OF A RECTANGULAR LAMINATED SOLENOID
FRAME MOUNTED WITHIN THE FRONT MECHANISM COMPARTMENT (FIG.
4.4.2, ITEM 8). ITS FUNCTION is THAT OF ROTATING THE CLOSE LATCH
THEREBY INITIATING THE CLOSING STROKE. IT MAY BE ENERGIZED BY
THE CLOSE BUTTON ON THE FACEPLATE OR BY A REMOTE CONTROL
DEVICE.
FOR THE CLOSING COIL TO BE OPERATIVE THE FOLLOWING
CONDITIONS MUST BE MET:
(A) BREAKER OPEN
(B) CLOSING SPRING FULLY CHARGED (SPRING LIMIT SWITCH CLOSED).
(C) TRIP LATCH AND LATCH ROLLER ENGAGED.
LATCH CHECKING SWITCH CLOSED. (REFER TO 4.20).
(D) ANTI-PUMP RELAY RESET. (IF PROVIDED REFER TO 5.3).
THE CLOSING COIL IS IDENTIFIED ON THE WIRING DIAGRAM BY THE
SYMBOL "CC".
4.17 CLOSING COIL LIMIT SWITCH AND ANTIPUMPING FEATURE
ALL ELECTRICALLY OPERATED BREAKERS ARE PROVIDED WITH AN
ANTIPUMPING FEATURE. ITS PURPOSE IS TO PREVENT REPEATED
CLOSING ATTEMPTS WHEN BREAKER IS TRIPPED WHILE THE CLOSING
CIRCUIT REMAINS ENERGIZED. (MAINTAINED AUTOMATIC CONTROL
CONTACT, ETC.).
FOR BREAKERS CONTROLLED BY LONG TIME OR
PERMANENTLY MAINTAINED CLOSE CONTACTS, THE OPTIONAL
ANTPUMP RELAY MUST BE USED. REFER TO SECTION 5.3 FOR
DETAILS.
THE STANDARD FEATURE, FOR BREAKERS CONTROLLED BY
MOMENTARY, OR SHORT-TIME MAINTAINED CLOSE CONTACTS AND
REOUIRING CLOSING SPRING CHARGING IN BREAKER OPEN
POSITION ONLY, DOES NOT INCORPORATE THE ANTIPUMP RELAY.
THE ANTIPUMPING FUNCTION IS PROVIDED BY THE CLOSE COIL
(CC) LIMIT SWITCHES LOCATED BELOW THE COIL (FIG. 4.4.2, ITEM 14).
WHEN THE COIL IS ENERGIZED, OR NORMALLY CLOSED "CC" SWITCH
CONTACT IN THE SPRING CHARGING MOTOR CIRCUIT OPENS AND
REMAINS OPEN UNTIL THE CLOSE COIL IS DE-ENERGIZED.
FIG. 4.14 SHUNT TRIP COILS
1. SHUNT TRIP COIL
2. USD RELAY TRIP COIL
4.15 AUXILIARY SWITCH
ON ALL H-3 UNITS A MULTI-SECTION ROTARY TYPE AUXILIARY
SWITCH CAN BE PROVIDED (FIG. 4.4. 1, ITEM 1 3). IT IS COUPLED
DIRECTLY TO THE CLOSING SHAFT AND OPERATES ON A SNAP-
ACTION PRINCIPLE WHICH PROVIDES QUICK BREAK SWITCHING. NO
AJUSTMENT IS REQUIRED AND THE SWITCH IS AVAILABLE IN THE
FOLLOWING CONTACT ARRANGEMENTS.
4 POLE, PROVIDING 2 NORMALLY OPEN AND 2 NORMALLY CLOSED.
8 POLE, PROVIDING 4 NORMALLY OPEN AND 4 NORMALLY CLOSED.
12 POLE, PROVIDING 6 NORMALLY OPEN AND 6 NORMALLY CLOSED.
16 POLE, PROVIDING 8 NORMALLY OPEN AND 8 NORMALLY CLOSED.
20 POLE, PROVIDING 10 NORMALLY OPEN AND10 NORMALLY CLOSED
NOTE THAT CONTACTS AVAILABLE FOR EXTERNAL USE WILL
BE REDUCED BY
THE SYMBOL "b".
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15
BY A CAM LOCATED ON THE REAR OF THE CRANK ASSEMBLY. AS
THE CRANK PASSES THROUGH TOP-DEAD-CENTRE AND THE
RATCHET WHEEL BEARING APPROACHES THE CLOSE LATCH, THE
CAM OPERATES THE LEVER AND THE SWITCH DE-ENERGIZES THE
MOTOR. THE LEVER IS RESET WHEN THE MAIN SPRING
DISCHARGES. NO ADJUSTMENT IS REQUIRED FOR THE SPRING
LIMIT SWITCH.
IT IS IDENTIFIED ON THE WIRING DIAGRAM BY THE SYMBOL
"SLS".
4.20 LATCH CHECK SWITCH (LCS)
THE LATCH CHECK SWITCH IS PROVIDED ON ELECTRICALLY
OPERATED BREAKERS TO PREVENT ANY ATTEMPTED ELECTRICAL
CLOSING UNTIL BREAKER CLOSING MECHANISM IS SET AND READY
FOR THE CLOSING OPERATION. IT IS INSTALLED TO AN ADJUSTABLE
MOUNTING PLATE ON THE OUTSIDE OF THE LEFT HAND MECHANISM
SIDE PLATE AND OPERATED BY THE TRIP SHAFT LEVER. THE SWITCH
CONTACT IS CONNECTED IN SERIES WITH THE CLOSING COIL AND IS
CLOSED ONLY WHEN THE TRIP LATCH AND LATCH ROLLER ARE
PROPERLY ENGAGED.
FOR SWITCH TO BE CLOSED THE FOLLOWING CONDITIONS MUST
BE MET.
(A) DRAW-OUT MECHANRM GATE FULLY CLOSED.
(B)MANUAL TRIP BUTTON RELEASED.
(C) CLOSING SPRING FULLY-CHARGED.
IF ADDITIONAL OPTIONAL DEVICES ARE PROVIDED, THEIR
POSITIONS HAVE TO BE AS FOLLOWS:
(D) UNDERVOLTAGE TRIP DEVICE - ENERGIZED.
(E) OVERLOAD LOCKOUT MECHANISM - RESET.
(F) DOOR INTERLOCK - ENCLOSURE DOOR CLOSED.
(G) FACEPLATE KEY INTERLOCK - UNLOCKED, KEY TRAPPED.
(H) BLOWN FUSE INDICATOR - RESET.
(I) DOOR KEY INTERLOCK - UNLOCKED, KEY TRAPPED.
(K) MECHANICAL INTERLOCK BETWEEN BREAKERS - ALTERNATE
BREAKER(S) OPEN.
ITEMS (I) & (K) ARE APPLICABLE ONLY WHEN THE BREAKER IS IN
THE "OPERATING" POSITION.
THE LATCH CHECK SWITCH IS IDENTIFIED ON WIRING DIAGRAMS
BY THE SYMBOL "LCS".
SHOULD THE BREAKER BE TRIPPED BEFORE THE CLOSE CIRCUIT
HAS BEEN DE-ENERGIZED, SPRING RECHARGING FUNCTION AND
CONSEQUENTLY BREAKER CLOSING IS BLOCKED. THE CLOSING
COIL SWITCH CONTACTS ARE IDENTIFIED ON THE WIRING DIAGRAM
BY THE SYMBOL "CC".
4.18 SPRING CHARGING MOTOR (SCM)
ALL ELECTRICALLY OPERATED BREAKERS EMPLOY A SERIES
WOUND GEAR MOTOR TO CHARGE THE CLOSING SPRING (FIG. 4.4.2,
ITEM 9). THE REDUCTION GEAR COMPARTMENT IS SEALED AND
LUBRICATED FOR LIFE AND THE ARMATURE BEARING SIMILARLY
REQUIRES NO MAINTENANCE LUBRICATION.
THE CHARGING MOTOR CUT OFF SWITCH MOUNTED ON THE
FACEPLATE PERMITS THE MOTOR TO BE DE-ENERGIZED DURING
MAINTENANCE OR INSPECTION (FIG. 3.3.2, ITEM 9). IT TAKES
APPROXIMATELY 4 SECONDS FOR THE MOTOR TO CHARGE THE
CLOSING SPRING.
TWO CHARGING MOTOR CONTROL CIRCUIT OPTIONS ARE
AVAILABLE. BREAKERS NOT REQUIRING IMMEDIATE RECLOSURE
AFTER TRIPPING ARE WIRED TO PERMIT MOTOR CHARGING
OPERATION WHEN BREAKER IS IN THE OPEN POSITION ONLY. THIS IS
THE STANDARD AND PREFERRED ARRANGEMENT.
BREAKERS REQUIRING A FAST TRIPPING RECLOSING FUNCTION
(AUTOMATIC CONTROL OR TRANSFER SCHEMES ETC. AS WELL AS ALL
BREAKERS EQUIPPED WITH THE ANTI PUMP RELAY) ARE WIRED TO
PERMIT THE SPRING TO BE IN THE CHARGED POS1TION AT ALL TIMES,
I.E. IMMEDIATE RECHARGE AFTER DISCHARGE REGARDLESS OF
WHETHER THE BREAKER IS IN THE OPEN OR CLOSED POSITION.
THE CHARGING MOTOR IS IDENTIFIED ON THE WIRING DIAGRAM
BY THE SYMBOL "SCM".
THE CHARGING MOTOR CUTOFF SWITCH IS IDENTIFIED BY THE
SYMBOL "IS".
4.19 SPRING LIMIT SWITCH (SLS)
ALL ELECTRICALLY OPERATED UNITS ARE EQUIPPED WITH A
LIMIT SWITCH WHICH STOPS THE MOTOR AT THE END Of THE
CHARGING STROKE (FIG. 4.4.2, ITEM 10). THE SWITCH IS MOUNTED
INSIDE THE LEFT HAND END OF THE FRONT CHANNEL (EXCEPT FOR
14" FRAME BREAKERS, WHERE IT IS LOCATED ON THE RIGHT). THE
SWITCH IS COUPLED WITH A LEVER (FIG. 4.4.2, ITEM 11) ACTUATED
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5. OPTIONAL COMPONENTS
5.1 MECHANICAL OPERATIONS COUNTER
A FIVE DIGIT MECHANICAL COUNTER CAN BE SUPPLIED,
MOUNTED IN THE FACEPLATE Of THE BREAKER (FIG. 3.3.2, ITEM 7).
THIS DEVICE IS MECHANICALLY DRIVEN BY THE "CHARGED/DIS-
CHARGED" INDICATOR. THE COUNTER OPERATES ONCE FOR EACH
CHARGING OF THE BREAKERMAIN SPRING. NO ADJUSTMENT OR
MAINTENANCE IS REQUIRED FOR SUCCESSFUL COUNTER OPERATION.
OPERATIONS COUNTERS ARE RECOMMENDED WHERE BREAKERS
WILL BE SUBJECTED TO FREQUENT OPERATIONS AS AN INDICATOR OF
THE RECOMMENDED MAINTENANCE INTERVALS.
5.2 CELL SWITCHES
CELL SWITCHES MOUNTED IN THE CRADLE CAN BE PROVIDED
WHEN REQUIRED TO SERVE AS POSITION INDICATORS OR AS
INTERLOCK BYPASSES. THE SWITCHES ARE OPERATED BY A BRACKET
ATTACHED TO THE BREAKER FRAME WHEN BREAKER IS CRANKED
INTO THE "OPERATING" POSITION.
EACH SWITCH CONTAINS ONE NORMALLY CLOSED AND ONE
NORMALLY OPEN ELECTRICALLY SEPARATE CONTACT. A TOTAL OF
SIX SWITCHES CAN BE SUPPLIED. THESE CONTACTS ARE RATED 10
AMPERES UP TO 300V A.C.
ON BREAKER FRAME SIZES 14 INCH AND 21 INCH (UP TO
2000 AMP), CELL SWITCHES MOUNT ON TOP OF THE CRADLE
BACKPAN. ON LARGER FRAME BREAKERS THEY MOUNT IN LINE
WITH THE SECONDARY DRAWOUT CONTACTS.
FIG. 5.2.1 CELL SWITCHES
1. CELL SWITCH OPERATING BRACKET
2. BREAKER FRAME
3. CELL SWITCH
4. CRADLE BACKPAN
5.3 ANTIPUMP RELAY
BREAKERS CONTROLLED BY LONG TIME OR PERMANENTLY
MAINTAINED CLOSE CONTACTS INCORPORATE TWO CLOSE COIL (CC)
LIMIT SWITCHES AND AN ANTIPUMP RELAY (A.P.R.). WHEN THE
CLOSING COIL IS ENERGIZED, BOTH "CC" SWITCHES ARE OPERATED. A
CLOSING CONTACT OF ONE "CC" SWITCH NOW ENERGIZES THE A.P.R.
COIL. ONE OF THE CLOSING A.P.R. CONTACTS PARALLELS THE "CC"
SWITCH CONTACT PROVIDING A.P.R. SEAL IN FUNCTION. A CLOSING
CONTACT Of THE SECOND "CC" SWITCH PARALLELS A NORMALLY
CLOSED A.P.R. CONTACT IN THE CLOSING COIL CIRCUIT MAINTAINING
CONTROL POWER TO THE CLOSING COIL UNTIL THE CLOSING SPRING
IS FULLY RELEASED AND THE BREAKER CLOSED. SPRING RELEASE
CAUSES DE-ENERGIZATION AND RESET OF THE CLOSING COIL AND
"CC" SWCHES WHILE THE A.P.R. REMAINS ENERGIZED AND ITS HELD
OPEN CONTACT IN THE CLOSING COIL CIRCUIT BLOCKS RE-
ENERGIZATION OF THE SAME UNTIL THE MAINTAINED CLOSING
CONTACT IS OPENED. THIS OPTION ALLOWS SPRING CHARGING
MOTOR RE-ENERGIZATION IMMEDIATELY AFTER CLOSING SPRING
DISCHARGE REGARDLESS Of OPEN OR CLOSED BREAKER POSITION
THEREBY PROVIDING FOR FAST TRIP - RECLOSE OPERATION.
THE ANTIPUMP RELAY AND ITS CONTACTS ARE IDENTIFIED
ON THE WIRING DIAGRAM BY THE SYMBOL "Y".
FIGURE 5.3 ANTIPUMP RELAY
5.4 UNDERVOLTAGE TRIP DEVICE
THE UNDERVOLTAGE TRIP DEVICE IS A SPRING LOADED
RECTANGULAR SOLENOID WHICH WILL TRIP THE BREAKER WHEN
ITS SUPPLY VOLTAGE TO THE SOLENOID DROPS BELOW A
PREDETERMINED LEVEL AND HOLDS THE BREAKER IN A TRIP FREE
STATE UNTIL SUPPLY VOLTAGE RETURNS. THE UNDERVOLTACE
TRIP WILL DROP TO TRIP THE BREAKER WHEN SUPPLY VOLTAGE
DROPS BELOW APPROXIMATELY 50% AND WILL PULL IN OR RESET
WHEN VOLTAGE RISES ABOVE 85%.
THIS DEVICE CAN BE SUPPLIED TO OPERATE
INSTANTANEOUSLY OR WITH THE ADDITION OF A MECHANICAL
ESCAPEMENT MECHANISM, CAN HAVE AN ADJUSTABLE 0 TO 5
SECOND TRIPPING DELAY.
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THE UNDERVOLTAGE TRIP IS MOUNTED ON THE LEFT HAND
MECHANISM SIDEPLATE AND ACTS DIRECTLY ON THE BREAKER'S
LEFT TRIP SHAFT LEVER.
IT IS IDENTIFIED BY THE SYMBOL "NV" ON THE WIRING DIAGRAM.
REFER TO SECTION 8.6 FOR ILLUSTRATION AND ADJUSTMENTS.
5.5 SAFETY INTERLOCK SWITCH (SIS)
THE SAFETY INTERLOCK SWITCH PROVIDES ADDITIONAL
SAFETY AGAINST PARALLELING TWO OR MORE BREAKERS USED IN
TRANSFER SCHEMES, ETC. THE SWITCH IS OPERATED BY THE CLOSE
LATCH RELEASE MECHANISM. ITS NORMALLY OPEN CONTACT IS
WIRED IN PARALLEL WITH THE NORMALLY OPEN SHUNT TRIP COIL
CLEARING CONTACT. IT MUST BE CONNECTED IN SERIES WITH A
NORMALLY OPEN AUXILIARY SWITCH CONTACT FROM THE OTHER
BREAKER BEING INTERLOCKED. WITH THE ALTERNATE BREAKER
CLOSED ATTEMPTS TO CLOSE THIS BREAKER BY MEANS OF THE
MANUAL CLOSE BUTTON OR EMERGENCY HANDLE WILL CLOSE SIS
CONTACT AND ENERGIZETHE SHUNT TRIP COIL. THIS OPERATES THE
BREAKER TRIP SHAFT BEFORE THE CLOSING SPRING IS RELEASED
RESULTING IN DRY RUN AND PREVENTS THE BREAKER FROM
CLOSING. NO ADJUSTMENT IS REQUIRED FOR THIS DEVICE. IT IS
IDENTIFIED BY THE SYMBOL "SIS" ON THE WIRING DIAGRAM, WHILE
THE NORMALLY OPEN AUXILIARY SWITCH CONTACT Of THE
ALTERNATE BREAKER IS IDENTIFIED BY THE SYMBOL "52-A".
FIG. 5.5 SAFETY INTERLOCK SWITCH
5.6 OVERLOAD LOCKOUT DEVICE
THE OVERLOAD LOCKOUT DEVICE PREVENTS RECLOSING OF THE
BREAKER EITHER MANUALLY OR ELECTRICALLY AFTER THE
BREAKER HAS BEEN TRIPPED BY THE OVERLOAD RELAY UNTIL THIS
DEVICE IS MANUALLY RESET.
FIG. 5.6 OVERLOAD LOCKOUT
(SHOWN IN OPERATED OR TRIP FREE POSITON)
1. TRIP COIL
2. FAULT INDICATION SWITCH
3. RESET BUTTON
5.7 DOOR INTERLOCK
ALL BREAKERS MAY BE FITTED WITH A DEVICE WHICH ACTS
TO TRIP THE BREAKER WHEN THE CELL DOOR IS OPENED. IN
OPERATION, THE INTERLOCK LEVER ACTS INTERNALLY ON THE
MANUAL TRIP BUTTON CAUSING IT TO BE DEPRESSED AND TRIP THE
BREAKER. THIS INTERLOCK MAY BE DEFEATED BY ARRESTING THE
MOVEMENT OF THE TRIP BUTTON. A SCREWDRIVE BLADE OR SIMILAR
TOOL INSERTED THROUGH THE SLOT IN THE TRIP BUTTON WILL
ALLOW THE DOOR TO BE OPENED WITHOUT TRIPPING THE CIRCUIT
BREAKER.
A SPECIAL USD RELAY TRIP COIL IS INSTALLED WITH THIS
DEVICE, ALONG WITH A SPRING OPERATED MECHANISM LINKING THE
TRIP COIL WITH THE MANUAL RESET BUTTON ON THE BREAKER
FACEPLATE. WHEN THE TRIP COIL IS ENERGIZED, IT TRIPS THE
BREAKER AND AT THE SAME TIME THE SPRING MECHANISM POPS THE
RESET BUTTON OUT ON THE FACEPLATE AND HOLDS THE TRIP COIL
PLUNGER UP, SO THAT THE BREAKER IS IN A TRIP-FREE STATE.
ON ELECTRICALLY OPERATED BREAKERS, THE LATCH CHECK
SWITCH WILL PREVENT OPERATION OF THE CLOSE COIL AND ANY
ATTEMPT TO MANUALLY CLOSE THE BREAKER WILL RESULT IN A
DRY RUN.
ONE SPDT SWITCH CAN BE PROVIDED WITH THIS DEVICE FOR
FAULT INDICATION. THESE CONTACTS ARE IDENTIFIED BY THE
SYMBOL "FI" ON THE WIRING DIAGRAM.
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FIG. 5.8.1 FACEPLATE KEY INTERLOCK ( SHOWN WITH THE
BREAKER HELD TRIP-FREE AND THE KEY FREE FOR REMOVAL).
1. LOCK
2. PLUNGER
3. MANUAL TRIP BUTTON
WHEN IT IS MORE DESIRABLE TO HAVE THE KEY INTERLOCK
MOUNTED ON THE BREAKER CUBICLE RATHER THAN ON AN
INDIVIDUAL BREAKER, A CELL KEY INTERLOCK CAN BE PROVIDED.
THIS IS A CABLE OPERATED DEVICE WHICH EMPLOYS A LOCK
MOUNTED ON BREAKER CUBICLE DOOR. A CABLE CONNECTS THE
LOCK TO A SHAFT AND LEVER ASSEMBLY MOUNTED ON THE CRADLE.
A SEPARATE CABLE SYSTEM ON THE BREAKER IS OPERATED BY THE
CRADLE LEVER TO TRIP THE BREAKER, AND HOLD IT TRIP-FREE
WHEN THE KEY HAS BEEN REMOVED FROM THE LOCK. THIS
INTERLOCK IS ONLY FUNCTIONAL WHEN THE BREAKER IS IN THE
"OPERATING" POSITION.
5.9 MECHANICAL INTERLOCK
MECHANICAL INTERLOCKS ARE AVAILABLE ON ALL H-3 BREAKER
FRAME SIZES (EXCEPT FOR 14 INCH SIZE). THEY ARE USED TO
MECHANICALLY INTERLOCK BREAKERS IN A TRANSFER SCHEME.
MECHANICAL INTERLOCKS ENSURE ONLY ONE BREAKER IS CLOSED
WHILE THE OTHER IS HELD IN A TRIP FREE POSITION.
MECHANICAL INTERLOCKS CONNECT WITH FLEXIBLE CABLE
THE CLOSING SHAFT Of ONE BREAKER TO THE TRIP SHAFT OF A
SECOND BREAKER, AND VICE VERSA. DRAWOUT BREAKERS ARE
INTERLOCKED BY CABLE CONNECTIONS BETWEEN THE TWO
CRADLES. THERE ARE NO PERMANENT CONNECTIONS BETWEEN THE
BREAKER AND MATCHING CRADLE WHEN INTERLOCKING IS
SUPPLIED, SO THE BREAKER CAN BE FREELY WITHDRAWN FROM THE
CELL. MECHANICAL INTERLOCKS ARE OPERABLE ONLY WHEN THE
BREAKER IS IN THE "OPERATING" POSITION. WHEN WITHDRAWN TO
THE "TEST" POSITION, BREAKERS ARE NOT INTERLOCKED AND CAN
BE TEST OPERATED IN THE NORMAL MANNER.
MECHANICAL INTERLOCKS ARE PRESET AT THE FACTORY AND
REOUIRE NO ADJUSTMENT.
FIG. 5.9.1 BREAKER PORTION OF MECHANICAL INTERLOCK
1. UPPER PLUNGER CONNECTED TO CLOSING SHAFT
2. LOWER PLUNGER CONNECTED TO TRIP SHAFT
FIG. 5.7 DOOR INTERLOCK
5.8 FACFPLATE KEY INTERLOCK AND CELL KEY INTERLOCK
A SINGLE OR DOUBLE FACEPLATE MOUNTED KEY INTERLOCK
CAN BE PROVIDED ON ALL BREAKERS. THE PLUNGER Of THE LOCK
ACTS INTERNALLY ON THE MANUAL TRIP BUTTON TO HOLD THE
BREAKER TRIP FREE AND PREVENT CLOSING WHEN THE KEY HAS
BEEN TURNED AND REMOVED. ON ELECTRICALLY OPERATED
BREAKERS, THIS ACTION ALSO OPERATES THE LATCH CHECK SWITCH
WHICH ISOLATES THE CLOSE COIL CIRCUIT.
THE FACEPLATE KEY INTERLOCK USES A TYPE VF LOCK WITH A
3/8 INCH PROJECTION.
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19
FIG. 5. 10.1 SHUTTERS - CLOSED POSITION
1. OPERATING MECHANISM
2. LINE SIDE BARRIER
3. LOAD SIDE BARRIER
4. PADLOCK BRACKET
FIG. 5.10.2 SHUTTERS - OPEN POSITION
1. LINE SIDE CONTACT STAB
2. LOAD SIDE CONTACT STAB
6. PRE-SERVICE INSPECTION
THE FOLLOWING ITEMS SHOULD BE SPECIFICALLYCHECKED
BEFORE A BREAKER IS PLACED IN SERVICE OR THE CONTROL CIRCUIT
IS ENERGIZED.
THE BREAKER SHOULD BE ROLLED OUT OF THE COMPARTMENT ON
THE FOLD- DOWN CRADLE RAILS, OR PLACED ON A BENCH FOR
BETTER ACCESSIBILITY. FOR FIXED MOUNTED BREAKERS, ENSURE
THAT THEY ARE ISOLATED FROM BOTH MAIN AND CONTROL POWER.
6.1 MAKE A VISUAL INSPECTION TO ENSURE THAT NO PARTS
HAVE BEEN DAMAGED OR FORCED OUT Of ALIGNMENT.
6.2 CHECK ALL THE CONTROL WIRING TO ENSURE THAT IT HAS
NOT BEEN DAMAGED.
6.3 CHECK THE DOOR INTERLOCK LEVER, FACE KEY INTERLOCK
AND ME- CHANICAL INTERLOCK MECHANISM FOR FREEDOM OF
MOVEMENT IF SUPPLIED.
6.4 ENSURE THAT THE USD RELAY SETTINGS CONFORM WITH
THE REOUIRED TRIPPING CHARACTERISTICS.
6.5 OPERATE BREAKER SEVERAL TIMES MANUALLY TO ENSURE
CORRECT OPERATION. NOTE THAT IF AN UNDERVOLTAGE TRIP
DEVICE IS INSTALLED, ITS MECHANISM MUST BE PHYSICALLY
BLOCKED IN THE OPERATED POSITION, SINCE WITHOUT CONTROL
POWER IT WILL HOLD THE CLOSING MECHANISM IN A TRIP-FREE
STATE AND PREVENT CLOSING. THE SAME APPLIES TO A DOOR
INTERLOCK IF INSTALLED. THE MANUAL TRIP BUTTON MUST BE
LOCKED IN THE "OUT" POSITION, OR THE INTERLOCK LEVER
BLOCKED IN THE "IN" POSITION WHEN THE CUBICLE DOOR IS NOT
CLOSED.
FIG. 5.9.2 CRADLE PORTION OF MECHANICAL INTERLOCK
1. INTERLOCK BRACKET ASSEMBLY
2. CABLES TO OTHER CRADLE
5.10 SHUTTERS
SHUTTERS ARE AVAIIABLE ON MOST FRAME SIZES Of BREAKERS
TO COVER BOTH LINE AND LOAD MAIN CONTACT STABS INSIDE THE
CRADLE.
THEY ARE CLOSED, COVERING THE CONTACTS WHEN BREAKER
IS WITHDRAWN FROM THE "OPERATING" POSITION AND ARE OPENED,
EXPOSING THE CONTACTS WHEN BREAKER IS CRANKED IN TO THE
"OPERATING" POSITION.
A PADLOCK BRACKET IS PROVIDED SO THAT SHUTTERS CAN BE
LOCKED IN THE CLOSED POSITION WHEN THE BREAKER IS REMOVED
FROM THE CRADLE.
THE SHUTTER MECHANISM IS OPERATED BY THE BREAKER
FRAME.
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