cutler-hammer instructions for installation, operation and
TRANSCRIPT
I.B. 3A74792H04
Effective 7/97
Cutler-Hammer
Instructions for Installation, Operation and Maintenance of Type VCP-W 38kV Vacuum Circuit Breakers
I.B. 3A74792H04 Page iii
Effective 7/97
Cutler-Hammer
Power Distribution Components Division
Five Parkway Center
Pittsburgh, PA 15220
All possible contingencies which may arise during installation, operation or maintenance, and all details andvariations of this equipment do not purport to be covered by these instructions. If further information isdesired by purchaser regarding his particular installation, operation or maintenance of particular equipment,contact a Cutler-Hammer representative.
IMPROPERLY INSTALLING OR MAINTAININGTHESE PRODUCTS CAN RESULT IN DEATH, SERI-OUS PERSONAL INJURY, OR PROPERTY DAMAGE.
READ AND UNDERSTAND THESE INSTRUCTIONSBEFORE ATTEMPTING ANY UNPACKING, ASSEM-BLY, OPERATION OR MAINTENANCE OF THE CIR-CUIT BREAKERS.
INSTALLATION OR MAINTENANCE SHOULD BEATTEMPTED ONLY BY QUALIFIED PERSONNEL.THIS INSTRUCTION BOOK SHOULD NOT BE CON-SIDERED ALL INCLUSIVE REGARDING INSTALLA-TION OR MAINTENANCE PROCEDURES. IF FUR-THER INFORMATION IS REQUIRED, YOU SHOULDCONTACT CUTLER-HAMMER.
THE CIRCUIT BREAKERS DESCRIBED IN THISBOOK ARE DESIGNED AND TESTED TO OPERATEWITHIN THEIR NAMEPLATE RATINGS. OPERATIONOUTSIDE OF THESE RATINGS MAY CAUSE THEEQUIPMENT TO FAIL, RESULTING IN DEATH, BOD-ILY INJURY AND PROPERTY DAMAGE.
ALL SAFETY CODES, SAFETY STANDARDSAND/OR REGULATIONS AS THEY MAY BEAPPLIED TO THIS TYPE OF EQUIPMENT MUST BESTRICTLY ADHERED TO.
! WARNING ! WARNING
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TABLE OF CONTENTS
PageSECTION 1: INTRODUCTION
1-1 Preliminary Comments and Safety Precautions..................................................................................................11-1.1 Warranty and Liability Information..........................................................................................................11-1.2 Safety Precautions .................................................................................................................................1
1-2 General Information.............................................................................................................................................11-3 Type VCP-W Vacuum Circuit Breaker Ratings (Table 1.1).................................................................................21-4 Outlines and Dimensions ....................................................................................................................................3
SECTION 2: SAFE PRACTICES
2-1 Recommendations ..............................................................................................................................................4
SECTION 3: RECEIVING, HANDLING AND STORAGE
3-1 General ...............................................................................................................................................................53-2 Receiving.............................................................................................................................................................53-3 Handling ..............................................................................................................................................................53-4 Storage ...............................................................................................................................................................63-5 Tools and Accessories ........................................................................................................................................73-6 Type VCP-W Vacuum Circuit Breaker Weights (Table 3.1) ................................................................................7
SECTION 4: INITIAL INSPECTION AND INSTALLATION
4-1 Introduction........................................................................................................................................................124-2 Manual Operation Check...................................................................................................................................124-3 Vacuum Interrupter Integrity..............................................................................................................................124-4 Insulation ...........................................................................................................................................................124-5 Contact Erosion and Wipe.................................................................................................................................124-6 Primary Circuit Resistance ................................................................................................................................124-7 Nameplate .........................................................................................................................................................124-8 Electrical Operation Check................................................................................................................................13
4-8.1 Circuit Breaker Insertion and Removal.................................................................................................134-8.2 Operation Check Performance.............................................................................................................14
4-9 Breaker/Structure Interfacing ............................................................................................................................144-9.1 Interface Interlocks ...............................................................................................................................144-9.2 Interfacing Check .................................................................................................................................14
SECTION 5: DESCRIPTION AND OPERATION
5-1 Introduction........................................................................................................................................................165-2 Interrupter Assembly .........................................................................................................................................16
5-2.1 Vacuum Interrupter...............................................................................................................................175-2.2 Contact Erosion Indication ...................................................................................................................175-2.3 Loading Spring Indication.....................................................................................................................185-2.4 Contact Wipe and Stroke .....................................................................................................................18
5-3 Stored Energy Mechanism ................................................................................................................................185-3.1 Operation of Stored Energy Mechanism ..............................................................................................185-3.2 Charging...............................................................................................................................................18
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Page
5-3.3 Closing Operation.................................................................................................................................205-3.4 Tripping Operation................................................................................................................................20
5-4 Control Schemes...............................................................................................................................................205-4.1 Timing...................................................................................................................................................205-4.2 Secondary Disconnects........................................................................................................................205-4.3 Undervoltage Trip Device.....................................................................................................................23
5-5 Interlocks and Interfacing ..................................................................................................................................245-6 Levering Mechanism .........................................................................................................................................245-7 Operations Counter ...........................................................................................................................................245-8 Ground Contact .................................................................................................................................................245-9 MOC and TOC Switch Operations ....................................................................................................................24
SECTION 6: INSPECTION, MAINTENANCE AND TROUBLESHOOTING
6-1 Introduction........................................................................................................................................................266-2 Frequency of Inspection and Maintenance .......................................................................................................26
6-2.1 Qualified Personnel ..............................................................................................................................266-2.2 Helpful Tools and Accessory Items ......................................................................................................266-2.3 General Torque Guidelines ..................................................................................................................26
6-3 Inspection and Maintenance Procedures ..........................................................................................................296-4 Vacuum Interrupter Integrity Test......................................................................................................................306-5 Contact Erosion.................................................................................................................................................306-6 Contact Wipe.....................................................................................................................................................306-7 Insulation ...........................................................................................................................................................316-8 Insulation Integrity Check ..................................................................................................................................316-9 Primary Circuit Resistance Check.....................................................................................................................326-10 Mechanism Check.............................................................................................................................................326-11 Lubrication.........................................................................................................................................................326-12 Troubleshooting Chart.......................................................................................................................................33
SECTION 7: RENEWAL PARTS
7-1 General .............................................................................................................................................................367-1.1 Ordering Instructions ............................................................................................................................36
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FIGURES
Figure Title Page
1-1 Type VCP-W 38kV Circuit Breaker Outlines and Dimensions ......................................................................3
3-1 Circuit Breaker Shown Mounted with Ramp Still in Shipping Position..........................................................53-2 Circuit Breaker Shown Being Moved Carefully Down Attached Ramp.........................................................63-3 Optional Fifth Wheel Shown in Use ..............................................................................................................63-4 Front View VCP-W 38kV Vacuum Circuit Breaker........................................................................................83-5 VCP-W 38kV Vacuum Circuit Breaker with Front Cover Removed ..............................................................93-6 Rear View VCP-W 38kV Vacuum Circuit Breaker ......................................................................................103-7 Typical VCP-W 38kV Escutcheon...............................................................................................................11
4-1 Type VCP-W Circuit Breaker Manual Charging Handle in Use ..................................................................124-2 Type VCP-W Circuit Breaker (Bottom View)...............................................................................................15
5-1 Rear View Showing Pole Unit Enclosure ....................................................................................................165-2 Plate Over Rear Truck Opening 2000A Breakers and Above.....................................................................165-3 Graphic Representation of Arc Interruption ................................................................................................175-4 Closing Cam and Trip Linkage....................................................................................................................195-5 Charging Schematic....................................................................................................................................215-6 Typical 38kV VCP-W “DC” and “AC” Control Schematics ..........................................................................225-7 Secondary Circuit Breaker Plug Shown Mounted Lower Left .....................................................................235-8 Undervoltage Trip Device Configuration .....................................................................................................25
6-1 Lubrication Points .......................................................................................................................................286-2 Rear Measurement for Contact Erosion Being Made (Circuit Breaker Closed)..........................................316-3 Graphical Representation of Contact Erosion Measurement (Circuit Breaker Closed) ..............................316-4 Side View of Loading Spring Indicator (Circuit Breaker Closed).................................................................326-5 Graphical Representation of Contact Wipe Measurement
of Loading Spring Indicator (Circuit Breaker Closed)..................................................................................32
TABLES
Figure Title Page
1.1 Type VCP-W Vacuum Circuit Breaker on Symmetrical Current Rating Basis ..............................................2
3.1 VCP-W Circuit Breaker Weights ...................................................................................................................7
5.1 Circuit Breaker Timing ................................................................................................................................23
6.1 Torque Guidelines.......................................................................................................................................276.2 Test Voltage................................................................................................................................................306.3 Typical Resistance Measurements .............................................................................................................33
7.1 Recommended Renewal Parts for ANSI Rated Breakers...........................................................................36
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SECTION 1: INTRODUCTION
1-1 PRELIMINARY COMMENTS AND SAFETY PRE-CAUTIONS
This technical document is intended to cover mostaspects associated with the installation, application,operation and maintenance of the VCP-W VacuumCircuit Breakers. It is provided as a guide for authorizedand qualified personnel only. Please refer to the specificWARNING and CAUTION in Section 1-1.2 before pro-ceeding. If further information is required by the pur-chaser regarding a particular installation, application ormaintenance activity, a Cutler-Hammer representativeshould be contacted.
1-1.1 WARRANTY AND LIABILITY INFORMATION
NO WARRANTIES, EXPRESSED OR IMPLIED,INCLUDING WARRANTIES OF FITNESS FOR A PAR-TICULAR PURPOSE OF MERCHANTABILITY, ORWARRANTIES ARISING FROM COURSE OF DEAL-ING OR USAGE OF TRADE, ARE MADE REGARDINGTHE INFORMATION, RECOMMENDATIONS ANDDESCRIPTIONS CONTAINED HEREIN. In no event willCutler-Hammer be responsible to the purchaser or userin contract, in tort (including negligence), strict liability orotherwise for any special, indirect, incidental or conse-quential damage or loss whatsoever, including but notlimited to damage or loss of use of equipment, plant orpower system, cost of capital, loss of power, additionalexpenses in the use of existing power facilities, orclaims against the purchaser or user by its customersresulting from the use of the information and descrip-tions contained herein.
1-1.2 SAFETY PRECAUTIONS
All safety codes, safety standards and/or regulationsmust be strictly observed in the installation, operationand maintenance of this device.
THE WARNINGS AND CAUTIONS INCLUDED ASPART OF THE PROCEDURAL STEPS IN THIS DOCU-MENT ARE FOR PERSONNEL SAFETY AND PRO-TECTION OF EQUIPMENT FROM DAMAGE. ANEXAMPLE OF A TYPICAL WARNING LABEL HEAD-
ING IS SHOWN ABOVE IN REVERSE TYPE TOFAMILIARIZE PERSONNEL WITH THE STYLE OFPRESENTATION. THIS WILL HELP TO INSURETHAT PERSONNEL ARE ALERT TO WARNINGS,WHICH MAY APPEAR THROUGHOUT THE DOCU-MENT. IN ADDITION, CAUTIONS ARE ALL UPPERCASE AND BOLDFACE AS SHOWN BELOW.
COMPLETELY READ AND UNDERSTAND THE MA-TERIAL PRESENTED IN THIS DOCUMENT BEFOREATTEMPTING INSTALLATION, OPERATION ORAPPLICATION OF THE EQUIPMENT. IN ADDITION,ONLY QUALIFIED PERSONS SHOULD BE PERMIT-TED TO PERFORM ANY WORK ASSOCIATED WITHTHE EQUIPMENT. ANY WIRING INSTRUCTIONSPRESENTED IN THIS DOCUMENT MUST BE FOL-LOWED PRECISELY. FAILURE TO DO SO COULDCAUSE PERMANENT EQUIPMENT DAMAGE.
1-2 GENERAL INFORMATION
The purpose of this book is to provide instructions forunpacking, storage, use, operation and maintenance ofType VCP-W 38kV Vacuum Circuit Breakers. They arehorizontal drawout, roll on the floor type removableinterrupting elements ideal for use in new metal-cladswitchgear, as well as for modernization and life exten-sion of existing switchgear. Designed to ANSI Stan-dards for reliable performance, ease of handling, andsimplified maintenance, VCP-W 38kV Vacuum CircuitBreakers provide reliable control and protection for elec-trical equipment and circuits. In addition, these techno-logically advanced circuit breakers provide higher insu-lation levels in less space, thus reducing the overallswitchgear size.
SATISFACTORY PERFORMANCE OF THESE CIR-CUIT BREAKERS IS CONTINGENT UPON PROPERAPPLICATION, CORRECT INSTALLATION ANDADEQUATE MAINTENANCE. THIS INSTRUCTIONBOOK MUST BE CAREFULLY READ AND FOL-LOWED IN ORDER TO OBTAIN OPTIMUM PERFOR-MANCE FOR LONG USEFUL LIFE OF THE CIRCUITBREAKERS.
! WARNING
! CAUTION
! WARNING
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THE CIRCUIT BREAKERS DESCRIBED IN THISBOOK ARE DESIGNED AND TESTED TO OPERATEWITHIN THEIR NAMEPLATE RATINGS. OPERATIONOUTSIDE OF THESE RATINGS MAY CAUSE THE
EQUIPMENT TO FAIL, RESULTING IN DEATH, BODI-LY INJURY AND PROPERTY DAMAGE.
ALL SAFETY CODES, SAFETY STANDARDSAND/OR REGULATIONS AS THEY MAY BE APPLIEDTO THIS TYPE OF EQUIPMENT MUST BE STRICTLYADHERED TO.
Identification Rated ValuesCircuit Nominal Voltage Insulation Level Current Inter- Maximum Transient Current ValuesBreaker Voltage Maximum Voltage Withstand Test Continuous Short rupting Permis- Recovery Closing Low Out of Capacitor Switching RatingsType Class Voltage Range Voltage Current Circuit Time sible Voltage Latching Inductive Phase General Purpose Definite Purpose
Factor at 60 Hz Current ➃ Tripping (TRV) Capability Switching Switching Overhead Cable Isolated Overhead Isolated Back to BackDelay E2 T2 (Momen- Line Charging Shunt Line Shunt Capacitor Switching
Rise tary) Current Current Capac- Current Capac- Cable CapacitorTime itor itor Charging Bank
Power Impulse 3 Second (2.7 K Bank Bank Current CurrentFrequency ➂ Short Times Current Current ➄(1 Minute) Time Rated
Current ShortCarrying CircuitCapability Current)
E K I Y
kV Class kV rms kV rms kV Peak Amperes, kA rms Cycles Seconds kV Peak µs kA Peak Amperes, kA Amperes, rms Amperes, rmsrms rms
380 VCP-W 16 34.5 38 1.0 80 170 600 16 5 2 71 125 43 15 4 5 50 100 5 250 50 250
➁ 1200 ➁
1600
2000
380 VCP-W 25 34.5 38 1.0 80 170 600 25 5 2 71 125 68 15 6.3 5 50 100 5 250 50 250
➁ 1200 ➁
1600
2000
380 VCP-W 32 34.5 38 1.0 80 170 600 31.5 5 2 71 125 85 15 7.9 5 50 100 5 250 50 250
➁ 1200 ➁
1600
2000
380 VCP-W 21 34.5 38 1.65 80 170 1200 21 5 2 71 125 95 15 5.3 5 50 100 5 250 50 250
➅ 2000 ➅
➀ KEMA tested to applicable ANSI Standards C37.04 - 1979, C37.09 - 1979, Proposed C37.06 - 199X, (operating duty, sequenceCO-15 seconds-CO). Typical operating time values: opening 45 ms, closing 75 ms, and reclosing 18 cycles.
➁ K=1.0, therefore E=E/K and I=KI, consult Application Data 32-265 for further information.➂ The ANSI standard requires 150 kV BIL, all ratings tested to 170 kV BIL.➃ 3-cycle interrupting time capability is available.➄ Tested at 20 kA, 4.4 kHz inrush current. Higher currents available, consult Cutler-Hammer.➅ At Rated maximum voltage divided by K=23 kV rms, Rated maximum symmetrical interrupting capability=KI=35 kA rms.
1-3 TY
PE
VC
P-W
VA
CU
UM
CIR
CU
IT B
RE
AK
ER
RA
TIN
GS
(TA
BL
E 1.1)
Table 1.1 Type VCP-W Vacuum Circuit Breaker on Symmetrical Current Rating Basis ➀
! WARNING
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DIMENSIONS ARETO BASE PLATE
THESE DIMENSIONS ARETO INTERMEDIATE PAN
21.0
0 [5
33]
17.3
[440
]17
.4 [4
41]
11.1
[283
]
17.4
[441
]
7.5
[191
]
15.6
[397
]7.
7 [1
95]
24.1 [611]18.2 [462]
15.9 [405]9.3 [236]
EARTHCONTACTS
1.3 [33]1.8 [46]
3.3 [85]
16.0 [407]
45.8 [1164]
47.1 [1197 REF]
27.6 [702]1.0 [26]
1.70 [43]7.7 [197]
600A - 1600A CONDUCTORS OTHERWISE SAME LENGTHAS 2000A CONDUCTORS
35.7 [908 REF]17.8 [454]
11.8 [300] 11.8 [300]
64.6
[164
1] .6 [1
4]
11.1
[283
REF
]
1.0
[26]
2.9
[75]
35.7 [908]17.9 [454]
16.4 [417] 16.4 [417]12.4 [314]
.2 [5]9.88 [251]
5.4 [137]
1.7[44]
CONTACT EROSIONINDICATOR FLAG
11.5 (TYP)[293]
DETAIL PLAN VIEWIN DIRECTION OF ARROW “X”
4.50 [114]
6.22 [158]
.63 [16] MIN TRAVELTO TRIP
1.93
8 [4
9]
1.56
3 [3
9.7]
OPEN/CLOSEFLOOR TRIPPERS
M.O.C. OPERATOR
SEE PLAN VIEWIN DIRECTION OF ARROW "X"
4.6[117]
TOC Operator
Figure 1-1 Type VCP-W 38kV Circuit Breaker Outlines and Dimensions (inches and [mm])
1-4 OUTLINES AND DIMENSIONS
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SECTION 2: SAFE PRACTICES
2-1 RECOMMENDATIONS
Type VCP-W Vacuum Circuit Breakers are equippedwith high speed, high energy operating mechanisms.They are designed with several built-in interlocks andsafety features to provide safe and proper operatingsequences. Cell interlocks used with drawout circuitbreakers are meant to interact with the appropriate cellinterface and levering mechanism.
TO PROTECT THE PERSONNEL ASSOCIATED WITHINSTALLATION, OPERATION, AND MAINTENANCEOF THESE CIRCUIT BREAKERS, THE FOLLOWINGPRACTICES MUST BE FOLLOWED:
• Only qualified persons, as defined in the NationalElectrical Safety Code, who are familiar with theinstallation and maintenance of medium voltage cir-cuits and equipment, should be permitted to work onthese circuit breakers.
• Read these instructions carefully before attemptingany installation, operation or maintenance of these cir-cuit breakers.
• Always remove the circuit breaker from its enclosurebefore performing any maintenance. Failure to do socould result in electrical shock leading to death,severe personal injury or property damage.
• Do not work on a drawout circuit breaker with a sec-ondary test coupler engaged. Failure to disconnectthe test coupler could result in an electrical shockleading to death, personal injury or property damage.
• Do not work on a closed circuit breaker or a breakerwith closing springs charged. The closing springsshould be discharged and the main circuit contactsopen before working on the circuit breaker. Failure todo so could result in cutting or crushing injuries.
• Do not use an open circuit breaker by itself as the solemeans of isolating a high voltage circuit. Remove thecircuit breaker to the Disconnect position and follow alllock-out and tagging rules of the National ElectricalCode and any other applicable codes, regulations andwork rules.
• Do not leave a drawout circuit breaker in an intermedi-ate position in the cell. Always have the circuit breakereither in the Disconnect/Test or Connected position.Failure to do so could result in a flash over and possi-ble death, personal injury or property damage.
• Always remove the maintenance tool from the circuitbreaker after charging the closing springs.
• Circuit breakers are equipped with safety interlocks.Do Not remove, interfere with or in any manner defeatthem. This may result in death, bodily injury or equip-ment damage.
• Do not work on a circuit breaker suspended from a lift-ing yoke or chains. Maintenance work should be per-formed on a solid work surface, such as the floor.
! WARNING
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SECTION 3: RECEIVING, HANDLING ANDSTORAGE
3-1 GENERAL
Type VCP-W Vacuum Circuit Breakers are subjected tocomplete factory production tests in accordance withANSI C37.09 and inspection before being packed. Theyare shipped in packages designed to provide maximumprotection to the equipment during shipment and stor-age and at the same time to provide convenient han-dling. Tools and accessories, such as the maintenancetool, are shipped separately.
3-2 RECEIVING
If the circuit breaker is not to be used immediately but isto be placed in storage, maximum protection can beobtained by keeping it packed as shipped.
Upon receipt of the equipment, inspect the containersfor any signs of damage or rough handling. Open thecontainers carefully to avoid any damage to the con-tents. Use a nail puller rather than a crow bar whenrequired. When opening the containers, be careful tosave any loose items or hardware that may be other-wise discarded with the packing material. Check thecontents of each package against the packing list.
Examine the circuit breaker for any signs of shippingdamage such as broken, missing or loose hardware,damaged or deformed insulation and other components.File claims immediately with the carrier if damage or lossis detected and notify the nearest Cutler-Hammer Office.
The VCP-W 38kV shipping container and pallet werespecifically designed to facilitate removal of the cir-cuit breaker from its pallet and container. Beforeproceeding, installation personnel should be famil-iar with the procedures outlined in Paragraph 3-3entitled “Handling.”
3-3 HANDLING
DO NOT USE ANY LIFTING DEVICE AS A PLAT-FORM FOR PERFORMING MAINTENANCE, REPAIROR ADJUSTMENT OF THE CIRCUIT BREAKER OR
FOR OPENING, CLOSING THE CONTACTS ORCHARGING THE SPRINGS. THE CIRCUIT BREAKERMAY SLIP OR FALL CAUSING SEVERE PERSONALINJURY. ALWAYS PERFORM MAINTENANCE,REPAIR AND ADJUSTMENTS ON A SOLID WORKSURFACE CAPABLE OF SUPPORTING THE CIR-CUIT BREAKER.
VCP-W 38kV Vacuum Circuit Breakers are shippedmounted to a skid specially designed to facilitateremoval of the breaker. Refer to Figures 3-1 and 3-2and proceed with the following steps:
AFTER REMOVING THE BRACKETS USED TOHOLD THE CIRCUIT BREAKER SECURELY TO THESHIPPING SKID AND ALL DURING THE PROCESSOF MOVING THE CIRCUIT BREAKER OFF OF THESHIPPING SKID AND DOWN THE RAMP TO THEFLOOR, TAKE SPECIAL PRECAUTIONS TO INSURETHAT THE CIRCUIT BREAKER IS MOVED SLOWLY
Figure 3-1 Circuit Breaker Shown Mounted with RampStill in Shipping Position
! WARNING
! WARNING
NOTICE
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AND UNDER CONTROL TO AVOID ANY ACCI-DENTS. THE CIRCUIT BREAKER IS A LARGEDEVICE WHICH COULD CAUSE SERIOUS BODILYINJURY IF IT IS TIPPED OVER OR PERMITTED TOROLL IN AN UNCONTROLLED MANNER.
Step 1: Remove the vertically mounted ramp from theshipping skid and place it on the floor next tothe skid. It should be positioned with the high-est part of the ramp next to the side of the skidwith the front of the circuit breaker.
Step 2: Remove the shipping brackets used to hold thecircuit breaker to the skid. Use the same ship-ping brackets and hardware to attach the rampto the shipping skid.
Step 3: Slowly move the circuit breaker forward anddown the ramp. Make certain that the circuitbreaker moves down the ramp slowly andstraight in line with the ramp. Once the circuitbreaker is on the floor, it can be easily maneu-vered via its integral wheels.
3-4 STORAGE
If the circuit breaker is to be placed in storage, maxi-mum protection can be obtained by keeping it packedas shipped. Before placing it in storage, checks shouldbe made to make sure that the circuit breaker is freefrom shipping damage and is in satisfactory operatingcondition.
The circuit breaker is shipped with its contacts open andclosing springs discharged. The indicators on the frontpanel should confirm this. Insert the maintenance tool inthe manual charge socket opening (Figure 3-7). Chargethe closing springs by pumping the handle up and downapproximately 38 times until a crisp metallic “click” isheard. This indicates that the closing springs arecharged and is shown by the closing spring “charged”(yellow) indicator. Remove the maintenance tool. Pushthe “manual close” button. The circuit breaker will closeas shown by the circuit breaker contacts “closed” (red)indicator. Push the “manual trip” button. The circuitbreaker will trip as shown by the circuit breaker contacts“open” (green) indicator. After completing this initial
Figure 3-2 Circuit Breaker Shown Being MovedCarefully Down Attached Ramp
Figure 3-3 Optional Fifth Wheel Shown in Use
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check, leave the closing springs “discharged” and circuitbreaker contacts “open”.
Outdoor storage is NOT recommended. If unavoidable,the outdoor location must be well drained and a tempo-rary shelter from sun, rain, snow, corrosive fumes, dirt,falling objects and excessive moisture must be provid-ed. Containers should be arranged to permit free circu-lation of air on all sides and temporary heaters shouldbe used to minimize condensation. Moisture can causerusting of metal parts and deterioration of high voltageinsulation. A heat level of approximately 400 watts foreach 100 cubic feet of volume is recommended with theheaters distributed uniformly throughout the structurenear the floor.
Indoor storage should be in a building with sufficientheat and air circulation to prevent condensation. If thebuilding is not heated, the same general rule for heat asfor outdoor storage should be applied.
3-5 TOOLS AND ACCESSORIES
Several tools and accessories, both standard andoptional are available for use with the circuit breaker.
Maintenance Tool (Standard): Used to charge closingsprings.
Lifting Yoke (Optional): Used to lift circuit breaker withoverhead lifting device.
Fifth Wheel (Optional): Used to maneuver a circuitbreaker on a flat, hard surface (Figure 3-3).
Table 3.1 VCP-W Circuit Breaker Weights ➀
Rating Pounds
380 VCP-W 16 600 10701200 10801600 10902000 1140
380 VCP-W 25 600 10701200 10801600 10902000 1140
380 VCP-W 32 600 10701200 10801600 10902000 1140
380 VCP-W 20 1200 10802000 1140
3-6 TYPE VCP-W VACUUM CIRCUIT BREAKERWEIGHTS (TABLE 3.1)
➀ Does not include shipping carton.
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Figure 3-4 Front View VCP-W 38kV Vacuum Circuit Breaker
Front Cover
Lift/Pull Handle
Contact Erosion Indicator Flags
Circuit Breaker Wheel
Secondary Contact Block
Alignment Rollers
3
4
1
2
5
6
1
2
5
4
3
6
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Figure 3-5 VCP-W 38kV Vacuum Circuit Breaker with Front Cover Removed
10
9
11
12
13
Shock Absorber
Shunt Trip Assembly
Spring Release (Close Coil) Assembly
Closing Cam
Open/Close Indicator
Operations Counter
L.H. Closing Spring
Motor Cutoff Switch
R.H. Closing Spring
Opening Spring
Manual Charge Socket
Ratchet Wheel
Charging Motor
1
2
5
4
3
6
1 2
5
4
3
6
7
8
10 9
11
12
13
7
8
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Figure 3-6 Rear View VCP-W 38kV Vacuum Circuit Breaker
Pole Unit
Primary Disconnect
Insulation Shroud
Opening to View Contact Erosion Mark
Circuit Breaker Wheel
Alignment Rollers
TOC Operator
1
2
5
4
3
6
1
2
5
4
3
67
7
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Figure 3-7 Typical VCP-W 38kV Escutcheon
Manual Charge Socket
Spring Charged/Discharged Indicator
Rating Nameplate
Manual Open Button
Manual Close Button
Open/Close Indicator
Operations Counter
1
2
5
4
3
6
7
1
2
5 4
36
7
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SECTION 4: INITIAL INSPECTION ANDINSTALLATION
4-1 INTRODUCTION
BEFORE PLACING THE CIRCUIT BREAKER IN SER-VICE, CAREFULLY FOLLOW THE INSTALLATIONPROCEDURE GIVEN BELOW. NOT FOLLOWINGTHE PROCEDURE CAN FAIL TO UNCOVER SHIP-PING DAMAGE THAT MAY RESULT IN INCORRECTCIRCUIT BREAKER OPERATION LEADING TODEATH, BODILY INJURY, AND EQUIPMENT DAM-AGE.
Before attempting to put a circuit breaker in service, itshould be carefully examined and operated manuallyand electrically. In addition, carefully examine the break-er for loose or obviously damaged parts. The followinginformation is a guide for performing recommendedchecks and tests.
4-2 MANUAL OPERATION CHECK
Refer to Figures 3-6 and 4-1 and then proceed by plac-ing the maintenance tool into the manual charge socketopening. Charge the closing springs with about 38 upand down strokes of the handle. When charging is com-plete the closing crank goes over center with an audibleCLICK and the springs Charged/Discharged indicatorshows “Charged.”
If the springs are to be charged on a closed circuitbreaker, no click is heard at the end of chargingoperation. Discontinue charging and remove themaintenance tool as soon as “Charged” flag is fullyvisible. Continued attempts to charge further mayresult in damage to the mechanism.
Remove the maintenance tool. Close and trip the circuitbreaker. Repeat several times.
4-3 VACUUM INTERRUPTER INTEGRITY
Using a dry, lint free cloth or paper towel, clean all theaccessible insulating surfaces of the pole units. Conducta vacuum interrupter integrity check as described inSection 6.
4-4 INSULATION
Check the circuit breaker’s primary and secondary insu-lation as described in Section 6.
4-5 CONTACT EROSION AND WIPE
Manually charge the closing springs and close the cir-cuit breaker. Check contact erosion and wipe asdescribed in Section 6.
4-6 PRIMARY CIRCUIT RESISTANCE
Check the primary circuit resistance as described inSection 6. The resistance should not exceed the valuesspecified. Record the values obtained for future refer-ence.
4-7 NAMEPLATE
Compare the circuit breaker nameplate information withswitchgear drawings for compatibility.
Figure 4-1 Type VCP-W Circuit Breaker ManualCharging Handle in Use
! WARNING
NOTICE
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4-8 ELECTRICAL OPERATION CHECK
After having completed all previous checks and tests,the circuit breaker is ready to be operated electrically. Itis preferred that this check be made with the circuitbreaker in a TEST position or by using a test cable, ifthe circuit breaker is outside the cell structure.
BEFORE INSERTING THE CIRCUIT BREAKER EXAM-INE THE INSIDE OF THE CELL STRUCTURE FOREXCESSIVE DIRT OR ANYTHING THAT MIGHT INTER-FERE WITH THE CIRCUIT BREAKER MOVEMENT.
EXTREME CAUTION MUST BE EXERCISED TOINSURE THAT PRIMARY CIRCUITS ARE NOT ENER-GIZED WHILE CHECKS ARE PERFORMED IN THECIRCUIT BREAKER COMPARTMENT. FAILURE TODO SO MAY RESULT IN PERSONAL INJURY ORDEATH.
The circuit breaker is normally tested electrically in itscell structure in the TEST position. To achieve the TESTposition, the circuit breaker must first be placed in thecell structure and the secondary contacts engaged. Tocomplete this testing procedure, the operator should firstbe familiar with inserting and removing the circuit break-er into and from the cell structure.
4-8.1 CIRCUIT BREAKER INSERTION ANDREMOVAL
The circuit breaker is designed to be in one of three dif-ferent positions within the structure with the door closed,DISCONNECT, TEST and CONNECTED. While in thestructure, the circuit breaker should never be allowed toremain at an intermediate position between two of thethree above mentioned designed positions.
Position the circuit breaker squarely in front of the struc-ture. Integrally mounted wheels facilitate circuit breakermovement outside of and into the structure. Once theside mounted circuit breaker alignment rollers arealigned with structure mounted alignment rails, push thecircuit breaker into the structure as far as it will move.The levering latch must be fully engaged or the circuitbreaker will not be able to be inserted. This first positionis the DISCONNECT position. Without moving the cir-
cuit breaker, manually engaging the secondary contactsnow makes this the TEST position.
To engage the secondary contacts, grasp the structuremounted secondary disconnect cage handle locatedbelow the left side of the circuit breaker, and pull it for-ward as far as possible to make the secondary engage-ment. As soon as control power is available, the motorwill charge the closing springs.
To move the circuit breaker to the CONNECTED posi-tion, engage the levering crank with the structure mount-ed levering shaft and begin turning the handle in aclockwise direction. Keep in mind that the levering crankcannot be engaged with the circuit breaker closed.Structure mounted positive guidance rails interface withthe circuit breaker alignment rollers to insure proper pri-mary and secondary connections.
The circuit breaker includes all necessary interlocksthat when interfaced with a compatible structure willrender the circuit breaker mechanism mechanicallyand electrically trip-free during the levering processinto or out of the structure. For detailed informationpertaining to individual circuit breaker interlocks,refer to Paragraph 4-9 in this section.
As the handle is turned, the circuit breaker will moveslowly toward the rear of the structure and the integrallymounted floor movement wheels will be lifted from thefloor of the structure. Eventually, the integrally mountedwheels are separated from the structure floor by approx-imately 1/8 inch, and the circuit breaker is suspended inthe structure. This design insures positive primary andsecondary connections, even if the assembly’s mount-ing conditions are less than ideal.
When the circuit breaker reaches the CONNECTEDposition, it will become impossible to continue turningthe levering crank in the clockwise direction. The sec-ondary contacts will automatically engage in the CON-NECTED position, if not already engaged manually inthe TEST position.
To remove the circuit breaker from the structure,reverse the procedure just described by turning the lev-ering crank in a counterclockwise direction. Keep inmind that safety interlocks may cause the circuit breakerto open and/or springs discharge during the removalprocedure. It depends on what condition the circuitbreaker was in as removal began.
! WARNING
! CAUTION
NOTICE
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4-8.2 OPERATION CHECK PERFORMANCE
Move the circuit breaker to the TEST position andengage the secondary contacts following the proceduredescribed in Paragraph 4-8.1. As soon as control powerbecomes available, the motor will charge the closingsprings with this condition indicated by a SpringCharged/Discharged Indicator on the front of the circuitbreaker (Figure 3-7). In addition, the status of the maincontacts, open or closed, is indicated on the front of thecircuit breaker.
Using the close and trip buttons on the front of the cir-cuit breaker, close and trip the circuit breaker severaltimes to verify the closing and tripping operations.Conclude the check by closing the circuit breaker.
4-9 BREAKER/STRUCTURE INTERFACING
Type VCP-W Vacuum Circuit Breakers are supplied witha series of interlocks to insure safe and proper interfac-ing between the circuit breaker and a compatible struc-ture compartment. The specific interlocks are describedin the next paragraph to provide the proper familiariza-tion. Once the interlocks are reviewed, an interfacingcheck can be performed as described in Paragraph 4-9.2.
4-9.1 INTERFACE INTERLOCKS
Each circuit breaker is supplied with the following inter-locks to insure safe and proper operation (Figure 4-2):
Code Plates
Code plates are mounted at the bottom of the circuitbreaker to prevent the insertion of a circuit breaker intoa structure of higher power rating. A set of two codeplates on the circuit breaker and two in the compartmentform this interlock.
Code plates do not block out control voltage orscheme incompatibility.
Close and Trip Floor Trippers
Mounted on the bottom of the circuit breaker, theseinterlocks interface with compatible structure interlocksto render the circuit breaker mechanism mechanicallyand electrically trip free during the levering process.
Anti-Close Interlock
This interlock prevents releasing the closing springselectrically or manually if the circuit breaker is alreadyclosed (Figure 5-5). On a closed circuit breaker, theinterlock lever moves toward the rear. In this position,the movement of the spring release clapper does not liftthe lever and thus the spring release latch cannot bemoved.
4-9.2 INTERFACING CHECK
Keep in mind that an interfacing check will be made witha compatible structure. As such, the instructions provid-ed with the assembly will suggest other interfacing con-ditions that should be observed and/or checked, such asprimary shutter operation, MOC/TOC operation and lev-ering handle insertion. A complete, coordinated inter-face check, therefore, will be a blend of the circuitbreaker instructions and those provided with the struc-tural assembly. Together all required standards are metand the ultimate in safety is achieved.
Insert the circuit breaker into the structure and lever itinto and out of each different position by following theprocedures described in Paragraph 4-8.1.
When the secondary contacts are manually engaged inthe TEST position, the motor will charge the closingsprings. Close the circuit breaker. Attempt to engage thelevering crank to begin moving the circuit breaker to theCONNECTED position. It will first be noticed that thelevering crank cannot be engaged with the breakerclosed. In addition, charged springs will be dischargedas the circuit breaker starts to move.
Once in the CONNECTED position, remove the leveringhandle, close the circuit breaker and the motor will begincharging the closing springs if control power is available.Once again engage the levering handle which can onlybe accomplished with the circuit breaker open.
Lever the circuit breaker toward the TEST position. Thecircuit breaker will be in a trip-free condition. Continue tolever the circuit breaker all the way to the TEST positionand the secondary contacts will be disengaged, nowmaking it the DISCONNECT position
Manually engage the secondary contacts and the motorwill charge the closing springs. Close the circuit breakerand begin to remove the circuit breaker to the WITH-DRAWN position by lifting and pulling on the Lift/Pullhandle. The circuit breaker will trip, close and trip as itmoves from the TEST position.
NOTICE
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The suggested combination of interface checks outlinedin the circuit breaker manual and structural assemblymanual are intended to verify safe and proper operation.If observed conditions are not as described, contactCutler-Hammer for assistance.
Figure 4-2 Type VCP-W Circuit Breaker (Bottom View)
Secondary Disconnect Plug
Close Floor Tripper
Trip Floor Tripper
1
2 5
4
3
MOC Operator
Code Plates
1 2 543
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SECTION 5: DESCRIPTION AND OPERATION
5-1 INTRODUCTION
The Type VCP-W 38kV Vacuum Circuit Breaker is ahorizontal drawout roll on the floor design for use in newswitchgear, as well as for modernization and life exten-sion of existing switchgear. VCP-W 38kV Circuit Break-ers meet or exceed all applicable ANSI and IEEE Stan-dards.
The circuit breaker is operated by a motor chargedspring type stored energy mechanism, charged normallyby an electric motor or manually by a manual chargingtool. The primary disconnecting contacts are self-align-ing, silver plated copper. VCP-W Circuit Breakers are ofa modular type construction containing a front accessiblemechanism with unobstructed access to control compo-nents. Self-contained vacuum interrupter pole unitassemblies are removable as complete individual units.
The primary insulation used in the circuit breaker design iscycloaliphatic epoxy. Type SIS, AWG #14 control wire withcross-linked polyolefin insulation is used throughout thecontrol circuits with all terminals being of the screw type.
This section describes the overall operation of the circuitbreaker as well as the function and operation of allmajor sub-assemblies and/or parts.
5-2 INTERRUPTER ASSEMBLY
The VCP-W 38kV design utilizes three individuallymounted and removable pole units. Each pole unit isenclosed in a four sided continuous chimney typecycloaliphatic epoxy support molding. Black insulatingshrouds cover and seal the openings where upper andlower primary conductors enter and exit the cycloali-phatic epoxy enclosure (Figure 5-1). The disconnectingends of the primary conductors utilize round, floatingtype primary disconnecting finger clusters for interfacingwith the switchgear structure mounted primary conduc-tors.
The rear portion of the circuit breaker truck, on whichthe pole units are mounted, utilizes a bolted on plate tocover a rectangular opening in the truck for circuitbreakers above 1600 amperes. Closure of the openingprovides for proper air circulation up through each poleunit enclosure on 2000 ampere and above circuit break-ers (Figure 5-2).
Figure 5-1 Rear View Showing Pole Unit Enclosure Figure 5-2 Plate Over Rear Truck Opening 2000ABreakers and Above
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THE PLATE BOLTED TO THE REAR RECTANGU-LAR OPENING ON ALL 2000 AMPERE AND ABOVECIRCUIT BREAKERS AND IDENTIFIED IN FIGURE 5-2 MUST BE BOLTED IN POSITION BEFORE PLAC-ING A CIRCUIT BREAKER IN SERVICE TO INSUREPROPER OPERATION WITHIN TEST PROVENPARAMETERS.
Vacuum interrupters are mounted vertically and support-ed from the fixed stem which is clamped to the top con-ductor. The exclusive current transfer system consists ofa series of plated, high-conductivity copper leaf conduc-tors that are pressed on the movable interrupter stem.This design provides a multipoint contact resulting in lowelectrical and thermal resistance. Utilizing this non-slid-ing current transfer system between the movable stemand the circuit breaker main conductor eliminates main-tenance of this joint.
Direct acting insulated operating rods in conjunction withthe circuit breaker’s mechanism provide a fixed amountof interrupter movable stem motion. This motion isdirectly related to the interrupter’s “Wipe” and “Stroke,”each of which is discussed in detail later in this section.
5-2.1 VACUUM INTERRUPTER
Type VCP-W 38kV Vacuum Circuit Breakers utilize vac-uum interrupters for interruption and switching functions.The vacuum interrupters use axial-magnetic, copperchrome contacts for superior dielectric strength, betterperformance characteristics, and lower chop current.Vacuum interruption provides the advantages ofenclosed interrupters, reduced size and weight, shortinterrupting time, long life, reduced maintenance, andenvironmental compatibility.
Arc interruption is simple and fast (Figure 5-3). In theclosed position, current flows through the interrupter.When the contacts are opened, the arc is drawnbetween the contact surfaces. It is moved rapidlyaround the slotted contact surfaces by a self-inducedmagnetic force which prevents gross contact erosion aswell as the formation of hot spots on contact surfaces.The arc burns in an ionized metal vapor which continu-ally leaves the contact area and condenses on the sur-rounding metal shield.
At current zero, the arc is extinguished and vapor produc-tion ceases. Very rapid dispersion, cooling, recombina-tion, and deionization of the metal vapor plasma, togetherwith the fast condensation of metal vapor products, cause
the vacuum to be quickly restored. Hence, the openedcontacts withstand the transient recovery voltage.
5-2.2 CONTACT EROSION INDICATION
The purpose of a contact erosion indicator is to monitorthe erosion of the vacuum interrupter contacts, which isvery minimal over time with vacuum interrupters utilizingcopper-chrome contact material. If contact erosionreaches 1/8 inch, the interrupter must be replaced. Twodifferent contact erosion indicators are provided formaximum user convenience.
Each phase of the circuit breaker is monitored inde-pendently by either of the two types of contact ero-sion indicators.
The first contact erosion indicator is monitored from therear of the circuit breaker. It provides a very accurateindication of contact erosion, and is the primary determi-nant of contact condition. A contact erosion indicatormark is located on the insulated operating rod of eachinterrupter (Figures 6-2 and 6-3).
Figure 5-3 Graphic Representation of Arc Interruption
Interruption
CurrentZero
Shield Involvement
High CurrentArc Mode
ArcInitiation
RecoveryVoltage
FaultCurrent
! CAUTION
NOTICE
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A second more convenient indicator is located on thefront of the circuit breaker (Figure 3-4). Small viewingwindows located on the front lower portion of the circuitbreaker truck provide a green and red “Go” or “No Go”flag indication of each vacuum interrupter’s contact ero-sion condition. This indicator is provided as a conve-nient reference when the circuit breaker is installed in itscubicle. As long as the line in the window is in the greenportion of the indicator, the contacts are satisfactory.When the line reaches the red portion of the indicator,the interrupter assembly must be replaced.
5-2.3 LOADING SPRING INDICATION
The contact loading spring indicator is an additionalmethod provided to indicate conditions within the vacuuminterrupter, as well as the overall system condition. The vis-ible indication, on each phase, is used to indicate whetherthe contact loading springs are maintaining the proper con-tact pressure to keep the contacts closed. Severe contacterosion or an adjustment need after an interrupter assem-bly replacement would result in an unacceptable indicationfrom this indicator (Figures 6-4 and 6-5).
5-2.4 CONTACT WIPE AND STROKE
Contact wipe is the indication of (1) the force holding thevacuum interrupter contacts closed and (2) the energyavailable to hammer the contacts open with sufficientspeed for interruption.
Stroke is the gap between fixed and moving contacts ofa vacuum interrupter with the circuit breaker open.
The circuit breaker mechanism provides a fixed amountof motion to the operating rods. The first portion of themotion is used to close the contacts (i.e. stroke) and theremainder is used to further compress the preloadedwipe spring. This additional compression is called wipe.Wipe and Stroke are thus related to each other. As thestroke increases due to the erosion of contacts, the wipedecreases. A great deal of effort has been spent in thedesign of all Cutler-Hammer vacuum circuit breakers, inorder to eliminate the need for field adjustments of wipeor stroke.
THERE IS NO PROVISION FOR IN SERVICEADJUSTMENTS OF CONTACT WIPE AND STROKE.ALL SUCH ADJUSTMENTS ARE FACTORY SETAND SHOULD NOT BE ATTEMPTED IN THE FIELD.
5-3 STORED ENERGY MECHANISM
KEEP HANDS AND FINGERS AWAY FROM THE CIR-CUIT BREAKER’S INTERNAL PARTS WHILE THECIRCUIT BREAKER CONTACTS ARE CLOSED ORTHE CLOSING SPRINGS ARE CHARGED. THE CIR-CUIT BREAKER CONTACTS MAY OPEN OR THECLOSING SPRINGS DISCHARGE CAUSING ACRUSHING INJURY. DISCHARGE THE SPRINGSAND OPEN THE CIRCUIT BREAKERS BEFORE PER-FORMING ANY CIRCUIT BREAKER MAINTENANCE,INSPECTION OR REPAIR.
The spring stored energy operating mechanism isarranged vertically in front of all VCP-W circuit breakers(Figure 3-5). It includes all the elements for storing theenergy, closing and tripping of the circuit breaker, aswell as manual and electrical controls. The manual con-trols are all front accessible. Motion to close and openthe interrupter contacts is provided through operatingrods connecting the mechanism pole shaft to the bellcranks of the interrupter assemblies.
5-3.1 OPERATION OF STORED ENERGYMECHANISM
The mechanism stores the closing energy by chargingthe closing springs. The mechanism may rest in any oneof the four positions shown in Figure 5-4 and as follows:
a. Circuit breaker open, closing springs dischargedb. Circuit breaker open, closing springs chargedc. Circuit breaker closed, closing springs dischargedd. Circuit breaker closed, closing springs charged
5-3.2 CHARGING
Figure 5-5 is a schematic view of the spring chargingparts of the stored energy mechanism.
The major component of the mechanism is a cam shaftassembly which consists of a drive shaft to which areattached two closing spring cranks (one on each end),the closing cam, drive plates, and a free-wheeling ratch-et wheel. The ratchet wheel is actuated by an oscillatingmechanism driven by the motor eccentric. As the ratchetwheel rotates, it pushes the drive plates which in turnrotate the closing spring cranks and the closing camwith it.
! CAUTION
! WARNING
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2
37
8 4
5
6
1
9
10
Figure 5-4 Closing Cam and Trip Linkage
Figure 5-4d Breaker closedand closing spring charged
Figure 5-4b Breaker openand closing spring charged
Figure 5-4a Breaker openand closing spring discharged
Figure 5-4c Breaker closedand closing spring discharged
9
5
6
4
8
73 10
2
1 Cam Shaft
Closing Cam
Trip Latch
Banana Link
Pole Shaft
Pole Unit Actuating Lever
Shock Absorber
Main Link Roller
Main Link
Trip Bar “D” Shaft
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The closing spring cranks have spring ends connectedto them, which are in turn coupled to the closing springs.As the cranks rotate, the closing springs are charged.When the closing springs are completely charged, thespring cranks go over dead center, and the closing stoproller comes against the spring release latch. The clos-ing springs are now held in the fully charged position.
Closing springs may also be charged manually. Insertthe maintenance tool in the manual charging socket.Move it up and down approximately 38 times until aclicking sound is heard, and the closing springs charg-ing indicator indicates “Charged.” Any further motion ofthe maintenance tool will result in free wheeling of theratchet wheel.
5-3.3 CLOSING OPERATION
Figure 5-4 shows the position of the closing cam andtripping linkage. Note that in Figure 5-4a in which thecircuit breaker is open and the closing springs are dis-charged, the trip “D” shaft and trip latch are in theunlatched position.
Once charged, the closing springs can be released toclose the circuit breaker by moving the spring releaselatch out of the way. This is done electrically or manuallyby depressing the spring release lever, which turns thespring release latch out of the way of the closing stoproller. The force of the closing spring rotates the camshaft through the spring cranks. The closing cam, beingattached to the cam shaft, in turn rotates the pole shaftthrough the main link to close the circuit breaker.
In Figure 5-4c the linkage is shown with the circuitbreaker in the closed position before the closing springshave been recharged. Interference of the trip “D” shaftwith the trip latch prevents the linkage from collapsing,and the circuit breaker is held closed.
Figure 5-4d shows the circuit breaker in the closed posi-tion after the closing springs have been recharged. Notethat the spring charging rotates the closing cam by onehalf turn. Since the cam surface in contact with the mainlink roller is cylindrical in this region, the spring chargingoperation does not affect the mechanism linkage.
Since the primary contacts are completely enclosed inthe vacuum interrupter and not adjustable in any way, a“Slow Close” capability is not provided with VCP-W cir-cuit breakers.
5-3.4 TRIPPING OPERATION
When the trip “D” shaft is turned either by the trip button
or trip coil, all links return to the original “open” conditionshown in Figure 5-4a.
5-4 CONTROL SCHEMES
There are two basic control schemes for 38kV VCP-Wcircuit breakers, one for DC control and one for AC con-trol voltages (Figure 5-6). There may be different controlvoltages or more than one tripping element, but the prin-cipal mode of operation is as follows:
As soon as the control power is applied, the springcharging motor automatically starts charging the closingsprings. When the springs are charged, the motor cut offLS1/bb switch turns the motor off. The circuit breakermay be closed by making the control switch close(CS/C) contact. Automatically upon closing of the circuitbreaker, the motor starts charging the closing springs.The circuit breaker may be tripped any time by makingthe control switch trip (CS/T) contact.
Note the position switch (PS1) contact in the springrelease circuit in the scheme. This contact remainsmade while the circuit breaker is being levered betweenthe TEST and CONNECTED positions. Consequently, itprevents the circuit breaker from closing automatically,even though the control close contact (CS/C) may havebeen made while the circuit breaker is levered to theCONNECTED position.
The position switch (PS2) contact is in the motor circuit.It prevents the motor from starting until the fully CON-NECTED position is reached and the secondary con-tacts are firmly engaged.
When the CS/C contact is made, the SR closes the cir-cuit breaker. If the CS/C contact is maintained after thecircuit breaker closes, the Y relay is picked up. The Y/acontact seals in Y until CS/C is opened. The Y/b contactopens the SR circuit, so that even though the circuitbreaker would subsequently open, it could not bereclosed before CS/C was released and remade. This isthe anti-pump function.
5-4.1 TIMING
The opening and closing times for the circuit breakersvary depending upon the control voltage and the powerrating. Typical values for 38kV VCP-W circuit breakersare shown in Table 5.1.
5-4.2 SECONDARY DISCONNECTS
The circuit breaker control wiring is arranged to connect
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12
4
11
8
14
10
2
9
13
7
1
3
6
5
Breaker Open, Springs Discharged Breaker Closed, Springs Charged
Pole Shaft
Anti-Close Interlock
Spring Release (Close) Latch
Spring Crank
Closing Spring
Closing Spring Fixed End
Spring Release (Close) Coil
Figure 5-5 Charging Schematic
9
11
5
6
4
8
7
3 10
2
1
12
Cam Shaft
Motor Ratchet Lever
Drive Pawl
Ratchet Wheel
Holding Pawl
Spring Release (Close) Clapper
Spring Release Latch (Close Roller)13
14
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5251
7
18
5453
17
5655
16
5857
15
8 9 10
22
3
a bM
YSR
ST1
WL GL RLSPRINGCHARGEDINDICATINGLIGHT
P
N
LS1bb
3 3A
1 2
24
4
CS C
7
PS1 Y LS2bb
LS2aa
4
LCb
21
Y
b
20
5
a
a
6
19
1314
109
a b b
CST PR
ST2
UV
9UV
10UV
9A10
A
13
12
14
a
a
11
CUSTOMER MUST FURNISHTHIS “a” CONTACT FROM AUXILIARY SWITCH WHEN SECOND TRIP COIL OPTIONIS CHOSEN AND MAKE THE APPROPRIATE CONNECTIONS.
AUXILIARY SWITCH #2 OPTIONAL
a b ba b a b a b a
DC S
OURC
E
6
PS2
U24 U19U20U21U22U23 U16U17U18 U15
U1 U9U8U7U6U5U4U3U2 U10
OPTIONS
YSR
GL RL
1
2
CS C
7
Y LS2bb
LS2aa
4
LCb
21
Yb
b
20
5
a
9
16
14 5655
CST PR
AC S
OURC
E
13
AC (+)CAP TRIP DEVAC (-)
ST1
a
a
109
6 19
5251
7
18
5453
17
5857
15
8 10
22
3
a b b b
ST2
UV9U
V10
UV9A
10A
13
12
14
a
a
11
CUSTOMER MUST FURNISHTHIS “a” CONTACT FROM AUXILIARY SWITCH WHEN SECOND TRIP COIL OPTIONIS CHOSEN AND MAKE THE APPROPRIATE CONNECTIONS.
AUXILIARY SWITCH #2 OPTIONAL
a b ba b a b a b a
U24 U19U20U21U22U23 U16U17U18 U15
U1 U9U8U7U6U5U4U3U2 U10
OPTIONS
6
M
WLSPRINGCHARGEDINDICATINGLIGHT
LS1bb
3 3A
1 2
24
4
PS2 PSI
UV
14
9UV
10UV
11
FOR AC UVTRIP ONLY
Figure 5-6 Typical 38kV VCP-W “DC” and “AC” Control Schematics
BREAKER DC CONTROL SCHEMATIC8796C76H01
BREAKER AC CONTROL SCHEMATIC8796C76H02
CS – Breaker Control Switch – closeCCS – Breaker Control Switch – tripT
Y – Anti Pump Relay SR – Spring Release Coil (Close Coil) M – Spring Charging Motor ST – Shunt TripPR – Protective Relay
– Secondary Disconnect
OPERATION SWITCH TERMINAL
LS1 Open until springs ‘C’ and ‘NC’aa are fully charged Brown Switch
LS1 Closed until springs ‘C’ and ‘NO’bb are fully charged
LS2 Open until springs ‘C’ and ‘NC’aa are fully charged Black Switch
LS2 Closed until springs ‘C’ and ‘NO’bb are fully charged
LC Open until mechanism ‘C’ and ‘NO’is reset
PS1 Open in all except between ‘C’ and ‘NC’‘Test’ and ‘Connected’ positions
PS2 Closed in all except between ‘C’ and ‘NO’‘Test’ and ‘Connected’ positions
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a standard 24 point male plug with a correspondingswitchgear compartment mounted female plug. An addi-tional 24 point plug is optional.
Type VCP-W 38kV circuit breakers utilize fixed mountedmale plugs located under the left bottom portion of thecircuit breaker truck. When two 24 point plugs are sup-plied, they are mounted in a stacked arrangement(Figure 5-7). Fixed mounted circuit breaker secondaryplugs connect to corresponding movable female plugsmounted in the bottom of the switchgear compartment.
The switchgear compartment mounted secondaries areof a movable carriage design. Once the circuit breakeris in the TEST position, the structure mounted sec-ondary plug carriage can be manually unlatched andpulled forward until mating with the circuit breakermounted male plugs. To disengage the secondary plugsfrom the TEST position, simply push the carriage to therear. Secondary connections are automatically engagedor disengaged when moving into or out of the CON-NECTED position.
5-4.3 UNDERVOLTAGE TRIP DEVICE
The undervoltage trip device for VCP-W circuit breakersis an electromechanical device that operates to openthe circuit breaker at 30% or less of the voltage rating ofthe trip coil. The device does not open the circuit break-er at values above 60% of the voltage rating of its tripcoil. It may operate, however, to open the circuit breakerwhen the voltage across the trip coil is greater than30%, but less than 60% of the voltage rating of its tripcoil. The circuit breaker can be closed as long as thevoltage to the trip coil is maintained at 85% or above therated level. The undervoltage trip device is available
only as an instantaneous type with rated voltages of48VDC, 125VDC, 250VDC 120VAC and 240VAC.
For a basic understanding of the operation of the under-voltage trip device refer to the specific items identified inFigure 5-8 and the following operation description.
1. With the circuit breaker closed and sufficient voltageon the Undervoltage Trip Device coil, the movingclapper (1) is held to the stationary yoke (2) by themagnetic force produced by the coil (3) against theextension springs (4) pulling the moving clapperapart from the yoke.
2. The moving clapper is connected to the mechanismTrip D Shaft Lever (5) by a slotted link (6).
3. When the voltage to the Undervoltage Trip Coil goesdown as described earlier, the extension springsforce overcomes the reduced magnetic force andpulls the moving clapper up. The slotted link in turnupsets the Trip D Shaft and the circuit breaker tripsopen.
4. As the circuit breaker opens, the reset lever (8) con-nected to the pole shaft lever (7) operates to resetthe moving clapper. As long as the circuit breaker
Event Milliseconds (maximum)
Closing Time(From Initiation of Close 75 Signal to Contact Make)
Opening Time(Initiation of Trip Signal 45to Contact Break)
Reclosing Time(Initiation of Trip Signal 190to Contact Make)
Table 5.1 Circuit Breaker Timing
Figure 5-7 Secondary Circuit Breaker Plug ShownMounted Lower Left
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remains open, the reset lever holds down the movingclapper to the yoke.
5. When the circuit breaker closes, the reset levermoves away from the moving clapper. If the Under-voltage Trip Device coil has at least 85% of the ratedvoltage applied, the moving clapper is held to theyoke by the magnetic force, even though the resetlever has moved up.
5-5 INTERLOCKS AND INTERFACING
Refer to Paragraph 4-9 of this manual for detailed infor-mation concerning circuit breaker interlocks and theirinterfacing with a switchgear structure compartment. Inaddition, refer to the instruction manual supplied withthe switchgear assembly.
5-6 LEVERING MECHANISM
The purpose of the levering mechanism is to move thecircuit breaker into and out of the CONNECTED positionwithin the assembly structure. The levering mechanismused to move the 38kV VCP-W circuit breaker is a mini-mum effort recirculating ball drive design, and is part ofthe assembly structure cradle. For additional informationconcerning the levering mechanism, refer to the instruc-tion manual supplied with the switchgear assembly.Paragraph 4-8.1 of this manual provides details con-cerning the use of the levering mechanism to move thecircuit breaker into and out of the CONNECTED positionwithin the assembly structure.
5-7 OPERATIONS COUNTER
All circuit breakers are equipped with a mechanicaloperations counter. As the circuit breaker opens, thelinkage connected to the pole shaft lever advances thecounter reading by one (Figure 3-7).
5-8 GROUND CONTACT
The ground contact is an assembly of spring loaded fin-gers providing a disconnectable means for groundingthe circuit breaker chassis, after it has been insertedinto a switchgear structure. The ground contact is locat-ed on the lower left portion of the truck chassis. Anextension of the switchgear ground bus is secured tothe cell floor in such a position to engage the groundcontact automatically, when the circuit breaker is movedinto the DISCONNECT/TEST position. It remainsengaged in all other circuit breaker positions within thecell.
5-9 MOC AND TOC SWITCH OPERATIONS
A MOC operator integral to the circuit breaker engagesan operating lever of the Mechanism Operated CellSwitch (MOC) located in the switchgear cell. This MOCoperator permits the contacts of the MOC Switch to becorrelated with the circuit breaker’s contact position.
The cell mounted Truck Operated Cell Switch (TOC) isoperated by movement of the circuit breaker truck intoor out of the CONNECTED position.
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2 3
7
8
4
6
1
5
2
5
6
4 8
73
2
1 Moving Clapper
Stationary Yoke
UV Trip Device Coil
Extension Springs
Trip D Shaft Lever
Slotted Link
Pole Shaft Lever
Reset Lever
Figure 5-8 Undervoltage Trip Device Configuration
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SECTION 6: INSPECTION, MAINTENANCEAND TROUBLESHOOTING
6-1 INTRODUCTION
• DO NOT WORK ON A CIRCUIT BREAKER IN THE“CONNECTED” POSITION.
• DO NOT WORK ON A CIRCUIT BREAKER WITHSECONDARY DISCONNECTS ENGAGED.
• DO NOT WORK ON A CIRCUIT BREAKER WITHSPRINGS CHARGED OR CONTACTS CLOSED.
• DO NOT DEFEAT ANY SAFETY INTERLOCKS.
• DO NOT LEAVE MAINTENANCE TOOL IN THESOCKET AFTER CHARGING THE CLOSINGSPRINGS.
• DO NOT STAND LESS THAN FOUR METERSAWAY FROM THE BREAKER WHEN TESTINGFOR VACUUM INTEGRITY.
FAILURE TO FOLLOW ANY OF THESE INSTRUC-TIONS MAY CAUSE DEATH, SERIOUS BODILYINJURY, OR PROPERTY DAMAGE. SEE SECTION 2-SAFE PRACTICES FOR MORE INFORMATION.
6-2 FREQUENCY OF INSPECTION ANDMAINTENANCE
Periodic inspections and associated maintenance areessential to the safe and reliable operation of VCP-WVacuum Circuit Breakers. The inspection frequency andassociated maintenance recommended are intended toinsure the best possible ongoing service. It is imperativethat an established schedule be followed. To establishan exact schedule for a specific installation, use the fol-lowing guidelines:
1. In a clean, non-corrosive environment, inspect andmaintain each circuit breaker annually or every 500operations, which ever comes first.
2. For special conditions such as frequent circuit break-er operation, contaminated environments, and hightemperature/humidity conditions, the inspection fre-quency should be twice a year.
3. Inspect a circuit breaker every time it interrupts faultcurrent.
4. Follow the steps presented in Paragraph 6-3 entitled“Inspection and Maintenance Procedures” for sched-uled programs.
5. Create and maintain a dated permanent record of allinspections, maintenance performed, actions taken,observations made, and measurements taken. Notonly will this provide valuable historical information, itcan help to establish whether or not the presentschedule needs to be adjusted.
6. Perform ongoing visual inspections, when possible,of all equipment on a regular basis. Be alert for anaccumulation of dirt in and around the circuit break-ers, loose hardware or discolored insulation.
6-2.1 QUALIFIED PERSONNEL
For the purpose of operating switchgear equipment andassociated circuit breakers, only individuals thoroughlytrained in the operation of power circuit breakers andassociated equipment, and having knowledge of con-nected loads may be considered to be qualified. Referto further definitions in the National Electrical SafetyCode.
For the purpose of inspecting and maintaining suchequipment, a qualified person must also be trained inregard to the hazards inherent to working with electricityand the proper way to perform such work. Such an indi-vidual should be able to de-energize, clear and tag cir-cuits in accordance with established safety practices. Inaddition, these individuals should have access to and betrained in the use of protective equipment, such as rub-ber gloves and flash clothes.
All personnel should be familiar with and understand thematerial presented in this instruction manual and otherrelated manuals.
6-2.2 HELPFUL TOOLS AND ACCESSORY ITEMS
To simplify the performance of inspection and mainte-nance programs, the items described in Section 3-5 arerecommended.
6-2.3 GENERAL TORQUE GUIDELINES
Bolts and screws must be properly torqued. This isespecially true if parts and/or accessories are added orreplaced. Table 6.1 provides guidelines on torque lev-els. The table is intended as a general guideline and
! WARNING
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should be applied in conjunction with the experienceand good judgment of the individual performing thework.
OVER TORQUING CAN CAUSE PERMANENT DAM-AGE WHILE UNDER TORQUING WILL NOT PRO-VIDE THE PROPER CLAMPING FORCE AND MAYEVENTUALLY WORK LOOSE.
Table 6.1 Torque Guidelines
Bolt Size Torque (LB-IN)
8 - 32 24
10 - 32 36
1/4 - 20 72
5/16 - 18 144 (12lb-ft)
3/8 - 16 300 (25lb-ft)
1/2 - 13 540 (45lb-ft)
! CAUTION
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Figure 6-1 Lubrication Points
● Apply one drop of lightmachine oil such asMobil One at locationsshown.
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6-3 INSPECTION AND MAINTENANCE PROCEDURES
No./Section Inspection Item Criteria Inspection Method Corrective Action
1. Insulation Drive Insulator No dirt Visual Check Clean with lint-free clothand and orMolded Pole Unit Support No cracking Visual Check Replace cracked unit
Insulation Main Circuit to Ground Withstand Hipot Tester Clean and retest or replaceIntegrity
Between Main Circuit Withstand Hipot Tester Clean and retest or replaceTerminals
Control Circuit to Ground Withstand Hipot Tester Clean and retest or replace
2. Power Vacuum Interrupters Visibility of 3 front Visual/Measurement - Close the circuit If the front indicator marks areElements Contact Erosion Marks breaker and observe if all 3 front indicator in the red area and the rear
and Precise Measure- marks are in green area, and then measurement is not acceptable,ment from rear proceed as described in Paragraph 6-5 replace pole unit assembly
Contact wipe Measurement of Loading Spring as If measurement is not acceptable, measurement described in Paragraph 6-6 replace pole unit assembly
Adequate Vacuum Proceed with integrity check as If integrity check is not satisfactory, described in Paragraph 6-4 replace pole unit assembly
Primary Disconnects No burning or damage Visual Check Replace if burned, damagedor eroded
3. Control Closing and Tripping Device Smooth and correct Test closing and tripping of the Replace any defective device. Identify Circuit Including Disconnects operation by control circuit breaker twice per trouble-shooting chartParts power
Wiring Securely tied in Visual Check Repair or tie as necessaryproper place
Terminals Tight Visual Check Tighten or replace if necessary
Motor Smooth, Normal Functional Test Replace brushes or motorOperation
4. Operating Tightness of Hardware No loose or missing Visual and by feel Refer to Table 6.1 and tighten Mechanism parts or reinstate if necessary with
appropriate tools
Dust or Foreign Matter No dust or foreign Visual Check Clean as necessarymatter
Lubrication Smooth operation Sight, feel and per maintenance Refer to Figure 6-1, Paragraphand no excessive schedule 6-11 and lubricate very spar-wear ingly with light machine oil
Deformation or Excessive No excessive Visual and operational Remove cause and replace partsWear deformation or wear
Manual Operation Smooth operation Manual charging, closing Correct per troubleshooting and tripping chart if necessary
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6-4 VACUUM INTERRUPTER INTEGRITY TEST
Vacuum interrupters used in Type VCP-W 38kV Vac-uum Circuit Breakers are highly reliable interrupting ele-ments. Satisfactory performance of these devices isdependent upon the integrity of the vacuum in the inter-rupter and the internal dielectric strength. Both of theseparameters can be readily checked by a one minute achigh potential test. Refer to Table 6.2 for the appropriatetest voltage. During this test, the following warning mustbe observed:
APPLYING ABNORMALLY HIGH VOLTAGE ACROSSA PAIR OF CONTACTS IN VACUUM MAY PRODUCEX-RADIATION. THE RADIATION MAY INCREASEWITH THE INCREASE IN VOLTAGE AND/OR DE-CREASE IN CONTACT SPACING. X-RADIATIONPRODUCED DURING THIS TEST WITH RECOM-MENDED VOLTAGE AND NORMAL CONTACTSPACING IS EXTREMELY LOW AND WELL BELOWMAXIMUM PERMITTED BY STANDARDS. HOWEV-ER, AS A PRECAUTIONARY MEASURE AGAINSTPOSSIBILITY OF APPLICATION OF HIGHER THANRECOMMENDED VOLTAGE AND/OR BELOW NOR-MAL CONTACT SPACING, IT IS RECOMMENDEDTHAT ALL OPERATING PERSONNEL STAND ATLEAST FOUR METERS AWAY IN FRONT OF THECIRCUIT BREAKER.
With the circuit breaker open and sitting solidly on thefloor or secured in a fixed position, connect all top pri-mary studs (bars) together and to the high potentialmachine lead. Connect all bottom studs together andground them along with the circuit breaker frame. Startthe machine at zero potential, increase to appropriatetest voltage and maintain for one minute.
A successful withstand indicates that all interruptershave a satisfactory vacuum level. If there is a break-down, the defective interrupter or interrupters should beidentified by an individual test and replaced before plac-ing the circuit breaker in service.
After the high potential is removed, discharge any elec-trical charge that may be retained. To avoid any ambi-guity in the ac high potential test due to leakage or dis-placement (capacitive) current, the test unit should havesufficient volt-ampere capacity. It is recommended thatthe equipment be capable of delivering 25 milliamperesfor one minute.
Although an ac high potential test is recommended, a dctest may be performed if only a dc test unit is available.
In this case the equipment must be capable of delivering5 milliamperes for one minute to avoid ambiguity due tofield emission or leakage currents and the test voltageshall be as shown in Table 6.2.
The current delivery capability of 25 ma ac and 5 ma dcapply when all three VIs are tested in parallel. If individ-ual VIs are tested, current capability may be one third ofthese values.
SOME DC HIGH POTENTIAL UNITS, OPERATING ASUNFILTERED HALF-WAVE RECTIFIERS, ARE NOTSUITABLE FOR USE TO TEST VACUUM INTER-RUPTERS BECAUSE THE PEAK VOLTAGE AP-PEARING ACROSS THE INTERRUPTERS CAN BESUBSTANTIALLY GREATER THAN THE VALUEREAD ON THE METER.
6-5 CONTACT EROSION
In order to determine if the contacts have eroded to theextent that the interrupter must be replaced, close thecircuit breaker and observe the erosion mark on eachoperating rod from the rear of the circuit breaker. If themark on the interrupter stem is measured to be morethan 12 inches from the base of the interrupter, theinterrupter is satisfactory. If the mark is 12 inches orless, the interrupter assembly must be replaced (Figures6-2 and 6-3).
6-6 CONTACT WIPE
The adequacy of contact wipe can be determined by asimple measurement of each loading spring indicatorwith the circuit breaker closed. Refer to Figures 6-4 and6-5 and measure the indicator distance shown for eachinterrupter. If the measurement taken is in the range of0.91 to 1.22 inches, the contact wipe is adequate.
Vacuum Interrupter Integrity Test Voltage
ac 60 Hz dc
38 kV rms 60 kV rms 85 kV
Circuit Breaker RatedMaximum Voltage
Table 6.2 Test Voltage
! WARNING! CAUTION
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6-7 INSULATION
Type VCP-W 38kV Vacuum Circuit Breakers primarilyutilize cycloaliphatic epoxy insulation except, for exam-ple, the black insulating shrouds. Insulation mainte-nance primarily consists of keeping all insulating sur-faces clean. This can be done by wiping off all insulatingsurfaces with a dry lint free cloth or dry paper towel. Incase there is any tightly adhering dirt that will not comeoff by wiping, it can be removed with a mild solvent ordistilled water. Be sure that the surfaces are dry beforeplacing the circuit breaker in service. If a solvent isrequired to cut dirt, use Stoddard’s Solvent Cutler-Hammer 55812CA or commercial equivalent. Second-ary control wiring requires inspection for tightness of allconnections and damage to insulation.
6-8 INSULATION INTEGRITY CHECK
Primary Circuit:
The integrity of primary insulation may be checked bythe 60Hz AC high potential test. The test voltagedepends upon the maximum rated voltage of the circuit
breaker. For circuit breakers rated 38kV the test voltageis 60kV rms. Conduct the test as follows:
Close the circuit breaker. Connect the high potentiallead of the test machine to one of the poles of the circuitbreaker. Connect the remaining poles and circuit break-er frame to ground. Start the machine with output poten-tial at zero and increase to the test voltage. Maintain thetest voltage for one minute. Repeat for the remainingpoles. Successful withstand indicates satisfactory insu-lation strength of the primary circuit.
If a DC high potential machine is used, make certainthat the peak voltage does not exceed the peak of thecorresponding AC rms test voltage.
Secondary Circuit:
Connect all points of the secondary terminal block withshooting wire. Connect this wire to the high potentiallead of the test machine. Ground the circuit breakerframe. Starting with zero, increase the voltage to 1125volts rms. Maintain the voltage for one minute. Suc-cessful withstand indicates satisfactory insulationstrength of the secondary control circuit. Remove theshooting wire.
Figure 6-2 Rear Measurement for Contact ErosionBeing Made (Circuit Breaker Closed)
Figure 6-3 Graphical Representation of Contact ErosionMeasurement (Circuit Breaker Closed)
Base of Interrupter
Standard 12 inchMetal Scale
InchMeasurement Line
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6-9 PRIMARY CIRCUIT RESISTANCE CHECK
Since the main contacts are inside the vacuum cham-ber, they remain clean and require no maintenance atany time. Unlike many typical circuit breaker designs,VCP-W circuit breakers do not have sliding contacts atthe moving stem either. Instead they use a highly reli-able and unique flexible clamp design that eliminatesthe need for lubrication and inspection for wear.
If desired, the DC resistance of the primary circuit maybe measured as follows: close the circuit breaker, passat least 100 amps DC current through the circuit break-er. With a low resistance instrument, measure resis-tance across the studs on the circuit breaker for eachpole. The resistance should not exceed the valuesshown in Table 6.3.
6-10 MECHANISM CHECK
Make a careful visual inspection of the mechanism forany loose parts such as bolts, nuts, pins and rings.Check for excessive wear or damage to the circuitbreaker components. Operate the circuit breaker sever-al times manually and electrically. Check the closingand opening times to verify that they are in accordancewith the limits in Table 5.1.
6-11 LUBRICATION
All parts that require lubrication have been lubricatedduring the assembly with molybdenum disulphidegrease (Cutler-Hammer Material No. 53701QB). Over aperiod of time, this lubricant may be pushed out of theway or degrade. Proper lubrication at regular intervals isessential for maintaining the reliable performance of themechanism. Once a year or every 500 operationswhichever comes first, the circuit breaker should berelubricated. The locations shown in Figure 6-1 shouldbe lubricated with a drop of light machine oil.
After lubrication, operate the circuit breaker severaltimes manually and electrically.
Roller bearings are used on the pole shaft, the camshaft, the main link and the motor eccentric. Thesebearings are packed at the factory with a top grade slowoxidizing grease which normally should be effective formany years. They should not be disturbed unless there
Figure 6-4 Side View of Loading Spring Indicator(Circuit Breaker Closed)
Figure 6-5 Graphical Representation of Contact WipeMeasurement of Loading Spring Indicator (CircuitBreaker Closed)
0.91
"1.
22"
CONTACT WIPE
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is definite evidence of sluggishness, dirt or parts are dis-mantled for some reason.
If it becomes necessary to disassemble the mechanism,the bearings and related parts should be thoroughlycleaned. Remove old grease in a good grease solvent.Do not use carbon tetrachloride. They should then bewashed in light machine oil until the cleaner is removed.After the oil has been drawn off, the bearings should bepacked with Cutler-Hammer Grease 53701QB or equiv-alent.
Rated ContinuousCurrent (amperes)
600120016002000
Resistance(microohms)
92908872
Table 6.3 Typical Resistance Measurements
6-12 TROUBLESHOOTING CHART (Continued Next Page)
SYMPTOM INSPECTION AREA PROBABLE DEFECTS
Fails To Close
• Closing Springs not charged • Control Circuit • Control Power(fuse blown or switch off)
• Secondary Disconnects
• Motor Cut-off Switch(Poor or burned contacts,Lever not operational)
• Terminals and connectors(Poor or burned contacts)
• Motor(Brushes worn or commutatorsegment open)
• Mechanism • Pawls(Slipping or Broken)
• Ratchet Wheel(Teeth worn or broken)
• Cam Shaft Assembly(Sluggish or jammed)
• Oscillator(Reset spring off or broken)
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SYMPTOM INSPECTION AREA PROBABLE DEFECTS
6-12 TROUBLESHOOTING CHART (Continued Next Page)
Fails To Close
• Closing Spring charged but • No Closing Sound • Control Powercircuit breaker does not close (Close Coil does (Fuse blown or switch off)
not pick up)
• Secondary Disconnects
• Anti-Pump Relay(Y relay N. C. contact open or burned or relay picks up)
• Close Coil(Open or burned)
• Latch Check Switch(Contact open-bad switch or trip bar not reset)
• Auxiliary Switch(b contact open or burned)
• Motor Cut-off(Contacts open or burned)
• Trip Coil Assembly(Clapper fails to reset)
• Closing Sound • Pole Shaftbut no close (Not open fully)
• Trip Latch Reset Spring(Damaged or Missing)
• Trip Bar-D Shaft(Fails to remain reset)
• Trip Latch-Hatchet(Fails to remain reset)
• Trip Floor Tripper(Fails to remain reset)
• Close Latch(Binding)
• Close Latch Roller(Binding)
• Trip Circuit Energized
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6-12 TROUBLESHOOTING CHART
Undesirably Closes
• Control Circuit • Close Circuit(CS/C Getting Shorted)
• Mechanism • Close Release Latch(Fails to reset)
• Close Floor Tripper(Fails to reset)
Fails To Trip
• No Trip Sound • Control Circuit • Control Power(Fuse blown or switch off)
• Secondary Disconnect
• Auxiliary Switch(a contact not making, poor or burned)
• Trip Coil(Burned or open)
• Terminals and Connections(Poor or burned or open)
• Trip Mechanism • Trip Clapper(Jammed)
• Trip Sound • Trip Mechanism • Trip Bar, Trip LatchBut No Trip (Jammed)
• Pole Shaft(Jammed)
• Operating Rod Assembly(Broken or pins out)
• Vacuum Interrupter(One or more welded)
Undesirably Trips
• Control Circuit • Control Power(CS/T Switch, remains made)
• Mechanism • Trip Coil Clapper(Not resetting)
• Trip Bar or Trip Latch(Poor engagement of mating or worn surfaces)
• Trip Bar Reset Spring(Loss of torque)
SYMPTOM INSPECTION AREA PROBABLE DEFECTS
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SECTION 7: RENEWAL PARTS
7-1 GENERAL
In order to minimize production downtime, it is recom-mended that an adequate quantity of spare parts be car-ried in stock. The quantity will vary from customer tocustomer, depending upon the service severity and con-tinuity requirements. Each customer should develop hisown stock level based on operating experience. Refer toTable 7.1 for guidance.
7-1.1 ORDERING INSTRUCTIONS
a. Always specify the breaker rating information andshop order number.
b. Describe the item, give the style number, and specifythe quantity required.
c. Specify the voltage for electrical components.d. Specify the method of shipping desirede. Send all orders or correspondence to the nearest
Cutler-Hammer sales office.
LINE DESCRIPTION STYLE NUMBER QTYNO. VCP-W
Interrupter Assembly
1 380/16, 600A - 16kA 3A74837H01 32 380/16, 1200A - 16kA 3A74838H01 33 380/16, 1600A - 16kA 3A74839H01 3
4 380/16, 2000A - 16kA 3A74840H01 3
5 380/25, 600A - 25kA 3A74851H01 36 380/25, 1200A - 25kA 3A74852H01 37 380/25, 1600A - 25kA 3A74853H01 3
8 380/25, 2000A - 25kA 3A74854H01 3
7.1 Recommended Renewal Parts for ANSI Rated Breakers (Continued Next Page)
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LINE DESCRIPTION STYLE NUMBER QTYNO. VCP-W
9 380/32, 600A - 31.5kA 3A74858H01 310 380/32, 1200A - 31.5kA 3A74859H01 311 380/32, 1600A - 31.5kA 3A74860H01 3
12 380/32, 2000A - 31.5kA 3A74861H01 3
13 380/1500, 600A - 35kA 3A74865H01 314 380/1500, 1200A - 35kA 3A74866H01 315 380/1500, 1600A - 35kA 3A74867H01 3
16 380/1500, 2000A - 35kA 3A74868H01 3
Charging Motor
17 48VDC 699B196G06 118 125VDC/120VAC 699B196G04 119 250VDC/240VAC 699B196G05 1
20 MOTOR BRUSH KIT 8063A77G01 1
7.1 Recommended Renewal Parts for ANSI Rated Breakers (Continued Next Page)
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LINE DESCRIPTION STYLE NUMBER QTYNO. VCP-W
Spring Release Coils
21 48VDC 3759A76G11 122 125VDC/120VAC 3759A76G12 123 250VDC/240VAC 3759A76G13 1
24 RECTIFIER (120/240VAC) 3759A76G02 1
Anti Pump (Y) Relay
25 48VDC 8237A27H03 126 125VDC 8237A27H04 127 250VDC 8237A27H05 128 120VAC 8237A27H01 129 240VAC 8237A27H02 1
Shunt Trip Coils
30 24VDC 3759A76G14 131 48VDC 3759A76G11 132 125VDC/125VAC Cap Trip 3759A76G12 133 250VDC/240VAC Cap Trip 3759A76G13 1
Primary Disconnects
34 600A 5680B59G01 635 1200A 5680B60G01 636 1600A 5680B61G01 637 2000A 692C037G03 6
UV Trip Coils
38 48VDC 8064A19G01 139 125VDC 8064A19G02 140 250VDC 8064A19G03 141 120VAC 8064A19G07 142 240VAC 8064A19G08 1
7.1 Recommended Renewal Parts for ANSI Rated Breakers (Continued Next Page)
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LINE DESCRIPTION STYLE NUMBER QTYNO. VCP-W
43 Motor Cutoff Switch 699B199G04 1
44 Latch Check Switch 699B147H04 1
45 Position Switch 699B147H01 146 Position Switch 3759A93H02 1
47 Auxiliary Switch 5697B20H01 1
48 Trip D-Shaft 694C638G01 1
49 Trip Latch (Hatchet) 699B040G03 1
7.1 Recommended Renewal Parts for ANSI Rated Breakers (Continued Next Page)
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LINE DESCRIPTION STYLE NUMBER QTYNO. VCP-W
Ground Contact Assy.
50 16kA 8796C85G01 151 25kA 8796C85G02 152 31.5kA 8796C85G03 153 21/35kA 8796C85G04 1
54 Shock Absorber 5677B26H01 2
55 Front Panel (w/o ESCN) 4D13655H02 1
56 Breaker Rail Wheel 5680B22G01 4
57 Shutter Drive Roller 5680B24H02 2
58 Breaker Floor Wheel 3A74342H01 4
7.1 Recommended Renewal Parts for ANSI Rated Breakers (Continued Next Page)
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LINE DESCRIPTION STYLE NUMBER QTYNO. VCP-W
59 Fastener Kit 8061A01G01 1
60 Labels Kit 8295A45G01 1
Wiring Harness
61 Repair Kit 8796C82G01 1
Complete Replacement
62 STD 8796C82G02 163 With #2 AUX SW 8798C82G03 1
Undervoltage Kit
64 48VDC 8794C81G01 165 125VDC 8794C81G02 166 250VDC 8794C81G03 167 120VAC 8794C81G04 168 240VAC 8794C81G05 1
7.1 Recommended Renewal Parts for ANSI Rated Breakers
Closed Open
Discharged
Charged
Push toClose
Push toOpen
I.B. 3A74792H04
Cutler-HammerFive Parkway CenterPittsburgh, PA 15220
Effective 8/96 (ISI)Style 3A74792H04Printed in U.S.A.
This instruction booklet is published solely for informa-tion purposes and should not be considered all inclu-sive. If further information is required, you should con-sult Cutler-Hammer.
Sale of product shown in this literature is subject toterms and conditions outlined in appropriate Cutler-Hammer selling policies or other contractual agreementbetween the parties. This literature is not intended toand does not enlarge or add to any such contract. Thesole source governing the rights and remedies of anypurchaser of this equipment is the contract between thepurchaser and Cutler-Hammer.
NO WARRANTIES, EXPRESSED OR IMPLIED,INCLUDING WARRANTIES OF FITNESS FOR A PAR-TICULAR PURPOSE OR MERCHANTABILITY, ORWARRANTIES ARISING FROM COURSE OF DEAL-ING OR USAGE OF TRADE, ARE MADE REGARDINGTHE INFORMATION, RECOMMENDATIONS ANDDESCRIPTIONS CONTAINED HEREIN. In no eventwill Cutler-Hammer be responsible to the purchaser oruser in contract, in tort (including negligence), strict lia-bility or otherwise for any special, indirect, incidental orconsequential damage or loss whatsoever, including butnot limited to damage or loss of use of equipment, plantor power system, cost of capital, loss of power, addition-al expenses in the use of existing power facilities, orclaims against the purchaser or user by its customersresulting from the use of the information, recommenda-tions and description contained herein.