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REGULATORY INFORMATION DISTRIBUTION SYSTEM(RIDS)'OC.DATE:

89/03/21 NOTARIZED: NOACCESSION NBR:8903270066FACIL:

AUTH.NAMERHOADS,E.W.

RECIP.NAMEBERLINGER,C.

AUTHOR AFFILIATIONABB Power Distribution, Inc.

RECIPIENT AFFILIATIONNRC — No Detailed AffiliationGiven

NOTES:

SUBJECT: Part 21 rept re contaminated lubricant on operatingmechanisms of two circuit breakers.

DISTRIBUTION -CODE: IE19D COPIES RECEIVED:LTR ENCL SIZE-TITLE: Part 21 Rept (50 DKT)

DOCKET

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PIZASE HELP US TO REZXJCE WASTE! CGHI'ACT THE DOCUMEPZ CONI$QL DESK,RXM Pl-37 (EXT. 20079) KO XZJMZNATE YOUR KkK FROM DISTIKBVTIGNZZSTS POR DCCtMENI'S YOU DQNiT NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 25 ENCL 24

~ ~

March 21, 1989

lIK QD I7D6'QQDQDASEA BROWN BOVERI

8903270066 8903~i tTPDR ADQCK 05000316

PDRQ

Mr. Carl BerlingerU.S. Nuclear Regulatory CommissionWashington, D.C. 20555

Subject: ABB Power Distribution, Inc.Circuit Breaker Lubrication

This letter is to provide additional information and clarification to a 10CFR

Part 21 Report filed by the D.C, Cook Nuclear Plants of (AEP) Indiana andMichigan Power on March 3, 1989 concerning the contaminated lubricant on theoperating mechanisms of two (2) 5HK250 circuit breakers resulting in theirfailure to close on command and perform their safety related function.

The circuit breakers involved in this incident were 17 years old and theAnderol 757 lubricant used on the operating mechanism was reported to behardened and had changed color.

The instruction book for the 5HK 250 circuit breakers mentioned abovecontained the following statement on lubrication:

"All other mechanism parts, bearings, pins, etc. have been lubricated withANDEROL L757 manufactured by Tenneco Chemical, Inc. Intermediate Division.The circuit breaker requires no lubrication during its normal service life.However, if the grease should become contaminated or if parts are replaced,any relubrication should be done with NO-OX-ID or ANDEROL grease asapplicable."

Both of these statements on lubrication must be considered together. Thesecond statement concerning contamination or parts replacement means thatperiodically, at least when parts are replaced, relubrication is required.Also dependent upon the cleanliness of the environment, periodic checks forcontamination should be performed.

The full statement on circuit breaker lubrication from the 1972 InstructionBook is included (See Appendix "A").

Exposure of circuit breakers to dirty and dusty conditions during plantconstruction may have contributed to the condition of the breakers whichfailed to close. Cleaning of the circuit breakers by blowing with air orvacuuming does not alleviate contaminated lubricant conditions.

If the lubricant is found to be contaminated and dry (hardened and discolored)it must be removed with a solvent approved by NIOSH and relubricated. Thisrequires disassembly of the circuit breaker.

ABB Power Distribution Inc.

ABB Power Distribution Inc.4379 County Line RoadChalfont,PA 18914

Telephone:215 822 4270

Tetefax:215 822-4271

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Mr. Carl BerlingerMarch 21, 1989Page 2

This same condition could occur on the other medium voltage HK circuitbreakers and low voltage K-line circuit breakers manufactured by ASEA BrownBoveri. The lubrication instructions for both the low voltage and mediumvoltage circuit breakers are similar (See Appendix "B" & "C").

In addition to the Anderol 757 grease, the Anderol 732 spray lubricant may beused in an emergency as a temporary lubricant. In these cases, allow time forthe solvent to evaporate prior to mechanical operation. It is mandatory thatthe breaker undergo thorough lubrication with Anderol 757 at the nextmaintenance interval. Note: Some of the instruction books referred to thelubricant as Anderol L757; the "L" has been deleted and the same lubricant isidentified now as Anderol 757.

When lubrication maintenance is indicated, care should be taken to remove allexisting lubricant prior to application of new lubricant. Removal can beaccomplished for mechanical assemblies by applying Anderol 732 fluid greaseand wiping away the residue with a clean, lint-free cloth followed by theapplication of Anderol 757. Where Anderol 732 is used, allow time for thesolvent to evaporate prior to applying the final lubricant.

Additional information on maintenance and surveillance is contained in M.S.3.1.1.9-2B (Low Voltage Equipment) and M.S. 3.1.1.9-1B (Medium VoltageEquipment). Copies of these documents are included for your convenience.

This information is being sent to all Nuclear Plants that have ASEA BrownBoveri Low Voltage (K-Line) and Medium Voltage (HK) circuit breakers inNuclear Safety Related applications. A list of these plants is included asAppendix "D".

Prior company names that could appear on the circuit breaker name platesinclude ITE, ITE Imperial, Gould, Gould-Brown Boveri, Brown Boveri Electric,and BBC Brown Boveri.

The lubricants specified may be obtained directly from their manufacturers:

Anderol 757 and Anderol 732 are obtainable through:

Nuodex, Inc.Turner PlaceP.O. Box 365Piscataway, NJ 08854

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Mr. Carl BerlingerMarch 21, 1989Page 3

NO-OX-ID "A Special" is obtainable through:

Sanchem, Inc.1600 S. Canal StreetChicago, IL 60616

Prior to 1972 the circuit breaker lubricant (for all ratings) was Nebula EP5F(manufactured by Esso-Humble Oil Company, now EXXON). It was changed toAnderol 757 in March 1972 because the Anderol had better low temperatureproperties.

E. W. RhoadsManager, Quality Assurance

EWR/jm

Attachment

cc: K. Naidu

M MM

I t IM

4M-

& IM "II t tl '

APPENDIX "A"

ftilTAWIAft)WITCHG)AR

/RACxtRC lEAD scnfw

0RACK/NG RELEASE LEVER

PADLOcx LocKDvr PLATE

Ffft. 6 —Rackfng Mechanfsnt

RACKINO MECHANISM (Soe ffg, 6)

Tho circuit breaker racking mechanism is adjuslod forproper operation and should not be dlstvrbed vnloss itbecomes possible to close the breaker during a rackingoperation,

It may be possible that interlocked btocklng membersare not positioned property, which should be correctedas folfowsr

Remove tho tower front mochanbm covarplato andwith the circvit breaker closed, make adjustments byragufating tho tangih of connecting rod I1) for I/8 inchminimum to 3/16 Inch maxlmvm claaranc ~ at "A" be-tween trip link I3) and blacking lover I2).

LV5RICATIQN

Tho HK cfrcuit breakers oro lubricatod dvring factoryassembly as foffawsi

1, All mating surfaces of movIng current.carryingjoints have been tvbrlcatad with NCt OX.ID special

grado "A" grease manufactured by Dearborn ChemicalCampany.

2. Aff other mechanism ports, bearings, pins, etc.have been lubricated with ANDEROL L7$7 manvfactvradby Tenneco Chemical, Inc„ Intermediate Division.

Tho cfrcult breaker requires no Ivbricatfon dvring itsnormal service life. Hawaver, if the grease shovld ——-=becomo contaminated or lf parts are replaced, any ra.

- lvbrtcatlon should be done with HQ CtX-tD or AHDEROLgrease as applicable,

NOTESr

1. Do nat vso HO.OX.ID grease on any main andarcing contact surfaces.

2. It b recommended that the primary dbconnects bomaintained by renewing the NO OX ID grease duringmainten one ~ periods,

3. Da nat usa light ail ta Iubrfcalo any mechanismparts,

4. Tho chorpfnp motor is seated and no fubrication isreriulfede

"" "':)(tA.'18"!t

vq

APPENDIX "B" IB 6.1.2,7-l

Page 19

LUBRICATION

The K-line circuit breakers are lubricated during fac-tory assembly as follows:

1. All mating surfaces of moving current-carryingjoints have been lubricated with NO-OX-ID specialGrade "A" grease manufactured by Dearborn ChemicalCompany.

2. All other mechanism parts, bearings, pins, etc.have been lubricated with ANDEROL L?57 manufacturedby Tenneco Chemical,.lnc., Intermediate Division.

The circuit breaker requires no lubrication during itsnormal service life. However, if the grease shouldbecome contaminated or if parts are replaced, any re-Iubrication should be done with NO-OX-ID or ANDEROLgrease as applicable.

NOTES:

1. Do not use NO-OX-ID grease on any main andarcing contact surfaces.

2. It is recommended that the primary disconnects bemaintained by renewing the NO-OX-ID grease duringmaintenance periods.

3. Do not use light oil to lubricate any mechanismparts.

4. Do not allow grease to be deposited on any latchroller surface during relubrication.

5. The charging motor is sealed and no lubricationis required.

6. DO NOT LUBRICATE OVERCURRENT TRIP DEVICESOR OTHERWISE CLEAN OR SPRAY WITH ANY SUB-STANCE OTHER THAN AIR.

DIELECTRIC TEST

, If the insulation has become contaminated, or routinetests are required, the test voltages to be applied forone minute to test the ability of the insulation to with-stand overvoltages are as shown in Table 2, below.

It is not recommended that the motor be dielectrictested, but if desired, then test at 540 V ac or 760 V dc.

On K-600S through K-2000S circuil breakers, connectall sixteen terminals of the power shield solid state logicbox together and to ground when conducting tests listedin Table 2. These terminals are located under the lowerfront cover of the logic box.

An additional dielectric test should be performed onK-600$ through K-2000S circuit breakers as follows:Connect all sixteen terminals of the power shield solidstate logic box together and apply 500 V ac betweenthe sixteen terminals and metal parts normally grounded.

ELECTRICAL CHARACTERISTICS OF CONTROl. DEVICES

For closing and tripping currents, voltages andranges, refer to Table 3, page 20.

For undervoltage trip devices, standard voltages andoperating data, refer to Table 4, page 20.

Current values are average steady state values.Momentary inrush currents for all charging motors andac coils are approximately 6-8 times these values.

RENEWAL PARTS

We recommend only those renewal parts be stockedthat will be required to insure proper and timely mainte-nonce for normal operation of the circuit breakers.

Refer to Renewal Parts Bulletin RP 6.1.2.8 -1 for com-plete ordering information and Parts List. A copy of thisbulletin will be furnished on request.

The minimum quantiIy of assemblies and items recom-mended in this bulletin is predicated on infrequent re-placement of parts based on accumulated tests andoperating experience. Total assemblies are recom-mended for fast replacement, when necessary, to returnthe breaker to service as quickly as possible. Then cer-tain replaced assemblies, such as the stationary upperterminals, can be returned to the factory for nomjnalreconditioning. The bulletin contains specific part ordei ~

ing instructions; and if desired, specific instructionsregarding replacement of those part assemblies recom-mended, that are not obvious, are also available ifordered.

TABLE 2

TEST VOLTAGES TO BE APPLIEO FOR ONE MINUTETO TEST TNE ABILITY OF THE INSULATION TO IIITHSTANO OVERYOLTAGES

Breaker Open Breaker Closed Breaker Open'r Closed

Breaker in Serviceor

Aller Storage a. Between line andload terminalssnd me 1st partsnormally grounded.

b. Between line sndload terminals

Between terminalsand metal partsnormally grounded.

b. Between phases.

1650 Y ac -- 2300 V dc 1650 Y ac -- 2300 V dc 1125 Y ac -- 1600 V dc

a. Between control circuitand metal parts normallygrounded.NOTE: Ilolor oust be dts.connected Irom controlcircuit for this test.

— At le iShort Circuit

1320 V ac -- 1660 V dc

a and b ss above s and b ss above s as above

1320 Y ac -- IBBOVdc BOO V ac -- 1260 V do

) ) ~ lly ( V V ~ lg

IB 6.2.1.7

Page 10

APPENDIX "C"

PAGE 1 OF 2

5.9 OPERATING MECHANISM (See Figure 5)

The operating mechanism is adjusted at the factory forproper operation and should not be disturbed unless thecircuit breaker does not close electrically on reclosingduty. This condition is caused when the latch checkswitch (2) at right side of breaker (when used) is not act-uated. Circuit breaker should not close before trip latch(4) has reset.

Latch-check switch adjustments - made with latch (4)against stop pin (3):

1. Turn in adjusting screw (1) until contacts ofswitch (2) "break" as indicated by an audible clickor check with bell ringer.

2. Retract adjusting screw until switch contacts"make".

3. Rotate adjusting screw one turn more. (Adjust-ment screw is self-locking.)

rrrrr2

I

OPENING THER.H. HOUSING

pl

SHIM IF REQUIRED

CONTROLPAN

0

LEVERprvoTBRACKET

LEVERCONTROLDEVICE

SWITCHCRANK

Fig. 6 —Control Relay

RACKINGLEAD SCREW

5.11 RACKING MECHANISM (See Figure 7)

The circuit breaker racking mechanism is adjusted forproper operation and should not be disturbed unless itbecomes possible to close the breaker during a rackingoperation.

If it is possible to close breaker during a rackingoperation, it may be that interlocked blocking membersare not positioned properly, which should be correctedas follows:

1. Remove the front mechanism coverplate.2. With circuit breaker closed, make adjustments by

regulating length of connecting rod (1) for 1/8" min.imum to 3/16" maximum clearance at "A"between triplink (3) and blocking lever (2).

Fig. 5 —Latch Check Switch Adjustment

5.10 CONTROL RE LAYADJ USTMENT

(See Figure 6)

A" 0)

'0)RACKING RELEASE

I LEVER

The control relay does not normally require any ad-

justment in the field. The gap between the control de-vice lever and the limit switch crank should be between0.06" and 0.09" with the closing springs charged. If thegap measurement is incorrect adjust all 5HK circuitbreakers except 5HK350, 3000 by shimming either atthe lever bracket or the control device mounting screwsas illustrated in Figure 6. Before changing shims at thetwo control device screws, loosen all three screws, re.place shims and then tighten all three screws. The5HK350, 3000 is adjusted by means of an adjusting headscrew fastened to the lever.

PADLOCK LOCKOUT,PLATE

Fig. 7 —Racking Mechanism

5.12 LUBRICATION

The HK circuit breakers are lubricated during factoryassembly as follows:

1. All mating surfaces of moving current carryingjoints have been lubricated with NO OX.ID specialgrade "A"grease manufactured by Sanchem lnc.

2. All other mechanism parts, bearings, pins, etc.have been lubricated with ANDEROL 757 manu.

"I"'«l~~< lies„

APPENDIX "C"

PAGE 2 OF 2

IB 6.2.1.7

Page 11

factured by Tenneco Chemical, Inc. IntermediateDivision.

In order to maintain reliable operation, it is import.ant that all circuit breakers be lubricated at all times. Allbearings and rolling surfaces that require lubricationhave been properly lubricated at the factory during as-

sembly and should not require any further lubricationduring the life of the equipment. However, even the fin-est greases have a tendency to oxidize with age, as

evidenced by hardening and darkening in color. In addi ~

tion to lubricant oxidation, frequent operation of the

breaker causes lubricant to be forced out from between

the bearing surfaces. When these changes occur, regreas-

ing is required to maintain reliable operation of thebreaker. Elimination of the hardened lubricant is es.

sential before regreasing is performed. A simple lubrica-tion will often clear up minor misoperations whichmight be mistaken for more serious trouble.

If the grease should become contaminated or parts

are replaced, lubrication should be'done with NO OX-IDor ANDEROL grease as applicable. Use of other greases

has not been proved by test and is not recommended.

5.14 TROUBLESHOOTING

TROUBLESHOOTING CHART

Problem

Breaker

Fails to

Close

Probable Cause

Low or Incorrect Control Volta e

aosing Springs Not Charged

Control Relay Limit Switch Out

of Adjustment

Breaker is not Racked into

Test or Connected Position

latch Check Switch not,Making (When Supplied)

Auxiliary Switch "b"

Contact not Making

Racking Release Lever

Unkage not properly adjusted

Corrective Action

Ad't to Proper Level

Adjust Per Section 5.10

Tum Operating Crank

Clockwise until lever is

locked into the desired

position

Adjust Per Section 5.9

Determine Cause and

Repair

Adjust per Section 5.11

The following chart lists typical problems, their causes

and corrective action required to remedy the malfunc-tion.

NOTES:1. Do not use NO OX-ID grease on any main and arc-

ing contact surfaces.

2. It is recommended that the primary disconnects be

maintained by renewing the NO.OX-ID grease dur-

ing maintenance periods.3. Do not use light oil to lubricate any mechanism

parts.4. The charging motor is sealed and no lubrication is

required.

5.13 DIELECTRIC TESTS

If it is desired to make dielectric tests during mainten.ance periods, the following test values should be used.

These are to be applied for a one-minute period.

TABLE 3. DIELECTRIC TEST VALUES

Breaker

Fails to

Trip

Excessive Friction

"Y"Contact not Makin

Undento)tege not operating

(When Supplied)

Defective Close Coil

Assembly

Low or Incorrect Control

Voltage

Auxiliary Switch "a"

Contact not Making

Defective Trip Coil

Assembly

Excessive Friction,h

Ins quent or tam-

inated Lubrication (See

Sec. 5.12)

Defective "Y" Coil Circuit

Low or Improper Voltage

Applied

Replace Close Coil

Assembly

Adjust to Proper Level

Determine Cause and

Repair

Replace Trip Coil

Assembly

Insufficient or Contam.

inated Lubrication

(See Sec. 5.12)

C(rcuit DC

"Caution —Improper "Y"circuit operation could per-

mitt

the breaker to pump to destruction.

Primary Circuit

'Secondary Grcuit (Control)

11.5 kv

1100 V

16 kv

1500 V

"Itis necessary that the changing motor be disconnectedfor this test by turning the motor disconnect switch tothe "OFF" position. If a test is desired on the motor,then the motor disconnect switch should be turned tothe "ON" position and the circuit ratested at 640 V,60 Hz or 760 VDC.

5.15 ELECTRICAL CHARACTERISTICS OFCONTROL DEVICES

For operating voltage ranges for various nominal controlvoltages refer to Table 4, Operating Voltage Ranges.

For average current values at various nominal controlvoltages, refer to Table 5, Average Current Values. Cur-rent values given in this table are average, steady. statevalues and momentary inrush currents for all chargingmotors and AC coils are approximately six to eight timesthese values.

c e II

Sheet 1 of 2

APPENDIX D

K-Line and HK Circuit Breakers

Arizona Public ServiceArkansas Power 6 LightBaltimore Gas 6 ElectricCarolina Power 6 LightCarolina Power 6 LightCincinnatti Gas 6 ElectricC.E.I.Commonwealth Edison

Commonwealth Edison

Connecticut Yankee

Consumers Power

Consumers Power

Detroit Edison

Duke Power

Duke Power

Duke Power

Duquesne LightFlorida Power CorporationFlorida Power 6 LightFlorida Power 6 LightGeorgia Power

Gulf States UtilitiesHouston Lighting 6 Power

Illinois Power

Indiana 6 Michigan

Iowa Electric Light 6 Power

Long Island LightSystems Energy Resources(Formerly Mississippi Power 6 Light)Niagara Mohawk

Northeast UtilitiesNorthern States Power

Palo Verde

Arkansas Nuclear One

Calvert CliffsBrunswick

Shearon HarrisZimmer

PerryZion

LaSalle County

Connecticut Yankee

Palisades

Midland

Fermi

Oconee

McGuire

Catawba

Beaver ValleyCrystal RiverSt. Lucie

Turkey PointVogtleRiver Bend

South Texas

ClintonCook

ArnoldShoreham

Grand Gulf

Nine Mile Point 2

Millstone 3

Prairie Island

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APPENDIX D

K-Line and HK Circuit BreakersC

Pennsylvania Power 6 LightPhiladelphia Electric Company

Philadelphia Electric Company

Portland General ElectricPublic Service Colorado

Public Service IndianaPublic Service New Hampshire

Public Service Electric 6 Gas

Public Service Electric 6 Gas

SMUD

South Carolina Electric & Gas

Southern California Edison

TVA

TVA

TVA

TVA

TVA

TVA

Texas UtilitiesVirginia Electric Power Company

Virginia Electric Power Company

WPPSS

CFE (Mexico)

Taiwan Power

Susquehanna

Peach Bottom

LimerickTrojanFt. St. VrainMarble HillSeabrook

Salem

Hope Creek

Rancho Seco

Summer

San Onofre

Sequoyah

Watts Bar

BellefonteHartsvillePhipps-Bend

Yellow Creek

Comanche Peak

SurryNorth Anna

WNP

Laguna Verde

Kuosheng

rl XIO/3efclP.

a.~s)fr s<8 Iiua)1'J Aff hl)e I ~ri.i-A

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ASEA BROWN BOVERI

« I~

MS 3.2.1.9-1 B

Maintenance and Surveillance

l-T-E. Medium-Voltage' Switchgear Equipment

«

«

*«

t«3'r

=«

t%

HK SwitchgearI B 3.2.1.7-1

5HK 250 and 350I B 6.2.1.7-1

7.5HK 500 and 15HK 500/750IB 6.2.2.7-1

15HK 1000IB 6.2.3.7-1

MS 3.2.1.9-']

Page 2

RECOMMENDED MAINTENANCE& SURVKlLLANCE5HK, 7.5HK 8c 15HK SWXTCHGEAR EQUIPMENT

EQUIPMENT MAINTENANCEPROGRAM

This Bulletin augments the informationand instructions provided in InstructionBulletin 3.2.1.7-1.

Switchgear installations which requireexceptional dependability due to serioussafety or economic consequences of op-erating problems should be given com-prehensive maintenance and surveillanceattention. This program recommendat-ion has been developed specifically foruse in Nuclear Power Generating Sta-tions but it is applicable to any install-ation where exceptional r'eliability is de-sired and a.preventive maintenance pro-gram is to be implemented.

Some maintenance activities are consid-ered essentia/ therefore ACTIVI'DESWHICH ARE MOST IMPORTANT TOASSURE AVOIDANCE OF PREDICT-ABLE PROBLEMS ARE UNDERLINED.

FREQUENCY OF MAINTENANCE

Suggested time frames in the program„are not absolute, they represent the bestgeneralized advice of the manufacturerfor equipment installed in a. clean,uncontaminated environment such asmay be found in a power generating-station. If e ui ment is in an area where,corrosive or conductive contaminents are

resent or if lar e amounts of airbornecontaminants will be e erienced theshortest interval of the ran e shown inthe e ui ment maintenance ro amshould be used. Further in hi hlcontaminated areas as described circuitbreaker servicin should be accom lishedat a maximum of two ear intervals.

If it becomes apparent after severalmaintenance cycles that certain act-ivities are not needed as frequently assuggested, or that increased frequencywould be prudent, the program should beadjusted to meet the specific needs ofthe installation.

RECORDS

Records are a key factor in a preventivemaintenance program and can providevital data for evaluating equiment cond-ition, when necessary, if the recordingsystem is-consistent, thorough and avail-able when needed. As a minimum therecords should contain the data and, forcircuit breakers, the number ofoperations at last maintenance in add-ition to results of testing. If observa-tions of equipment condition are record-ed, a realistic basis for adjusting main-tenance frequency willbe available.

SPARE PARTS

A major'actor in overall availability isdown-time-per-failure or mean-time-to-repair and although switchgear andassociated components enjoy favorablereliability expectations, random failureof a component can cause down-time orreduced capability if inadequate atten-tion is given to the spare partsinventory. A spare parts recommenda-tion for the switchgear equipment can beprovided to assist in selection of appro-priate parts. Storage of spares should bein a clean, dry area. Part access andidentification should permit promptavailability, when needed.

MS 3.1.1.9-2

Page 3

LUBRICANTS

Mechanisms(anti-

friction)

ANDEROL 757Tenneco Chem.

Inc.

Elec tricalContact

~Compound

NO-OX-ID"A Special"

Sanchem Chem. Co.

1. GENERAL

CAUTION: BE SURE THAT ALL ELEC-TRICAL SUPPLIES ARE OFF BEFOREPERFORMING ANY MAINTENANCEINSIDE EQUIPMENT.

a. The foQowin lubricants arerecommended:

2. RECEIPT AND STORAGE

Environm ental conditions duringtransit and storage can have a

substantial e ffect on equipmentreliability. Extended periods ofstorage with original shippingcovers in place must be avoided.

a. U on recei t e ui mentshould be ut into a ventilatedstora e area rotected fromthe weather. Tem eratureshould be maintained between40 F and 120 F humiditshould be maintained at 50%relative+ or belom. Shi incovers and/or boxes should beremoved.

Use of other lubricants risksincompatibility with originalmaterials or unproven per-form ance.

b. In ti htenin bolted conductorconnections use of a tor uemrench is recommended. Thefollomin tor ue levels millassure ood connections:

DRY THREAD TORQUE

+If relative humidity above50%%uo is anticipated, localizedheat, sources should be provid-ed, to - maintain equipm enttemperature above the dewpoint. One means of accom-plishing this is to energizeinternal equipment spaceheaters and store circuitbreakers mithin the equipment

~ enclosures.

BOLT DIA.

3/8"1/2"5/8 ll

TORQUE

15-25 ft. lb.30-45 ft. lb.50-75 ft. lb.

b. Under aQ conditions of trans-port and storage, equipmentshould be protected from

- direct impingement of mater,'looding and heavy contamin-ation, 'uch as constructiondust and dirt.

c. A clean and dry environmentshould be a continuing goal ofthe maintenance program foraQ electrical equipment.

d. Operating and maintenancepersonnel should be alert forunusual sounds (sizzling o"crackling) and smeQs (ozoneor burning) mhen in the vicin-ity of electrical equipment.

3. AT INSTALLATION (Repetition ofsome factory activity is suggesteddue to uncertainties of shipping,handling, etc.)

CAUTION: TURN OFF ALL POWERBEFORF WORKING INSIDE.

MS 3.1.1.9.2

Page 4

a. E ui ment mountin should beon level rails embedded flushwith the finished floor erinstallation dw s.

b. Removal of all shi in su-orts and installation of all

bus conductors (main andound) across shi in lits

should be verified.

c. Check all bolted bus connect-ions for ro er tor ue.

d. Check circuit breaker connec-tion wi e a l n NO-OX-ID corn ound to stationar

"connection stubs and rackinbreaker into connected osi«tion then out. Contact linesin com ound verif contact.

j. Millivolt drop and timingmeasurements on each circuitbreaker provide useful preop-er ation checks and valuable

'omparative data for futureuse.

aO Identif and ser vice circuitbreakers which are due. SeeCIRCUIT BREAKER SERVIC-

, ING section, page 6 of thisBulletin.

b. Exercise all circuit breakerswhich are not due for service.

4. SIX TO EIGHTEEN MONTH INTER-VALS

CAUTION:*

TURN OFF ALL POWERBEFORE WORKING INSIDE.

e. Exercise each circuit breaker(close and tri twice.)

f. Inspect primary conductorinsulation system, removecontamination accumulated instorage and installation.

g. Check " rimar cable connec-tions for ti ht hardware andro er stress relief. Check

all rimar connections toother electrical e ui ment.

h. Check control wire connec-tions - See 6b.

Check trip/racking interlockto verify no racking withbreaker closed and no closingunless breaker is latched inposition.

Co

d.

e.

Ins ect rimar interfaceconnections with othere ui ment for si s of exces-sive heat (Cable and bus con-nections usuall in the rearof the e ui ment.) Discolor»ation or embrittlement ofadjacent insulating materialsand conductor '. corrosion'rdiscoloration may indicate ahot joint. See HOT JOINTMAINTENANCE 8c JOINTCOVERS, Page 5.

Inspect prim ary cables forchafing at conduits or sup-ports.

Exercise the racking mechan-ism.,

NIS 3.2.1.9-1

Page r

5., ONE TO THREE YEAR INTER-VALS (Nuclear - Alternate refuel-ing shutdowns.)

CAU'IION: TURN OFF ALL POWERBEFORE WORKING INSIDE.

a. Clean contamination from'allrimar insulation with

vacuum distilled water or asolvent a roved NIOSH orlocal authorit as neces-sar . Ins ect for discolora-tion or other evidence ofexcessive heat. If foundroceed er HOT 'OINT

MAINTENANCE below.

b. Inspect control wiring bundlesfor discoloration due to heat,chafing'r other damage toinsulation.

c. Clean stationary breaker con-nection 'stubs in the 'enclosurewith a solvent approved byNIOSH or local authority.Inspect for evidence of con-tact galling, excessive heat,arcing or corrosion. If found,proceed per HOT JOINT

, MAINTENANCE,<below. Re-apply 'O-OX-ID compoundprior to reconnecting circuitbreaker.

NOTE: Protective relays should typ-, ically be checked for accuracy of cali-

bration at two to five years intervals, seemanufacturers instructions for detail.

6. TEN YEAR MAXIMUMINTERVAL

CAUTION: - TURN OFF ALL .POWERBEFORE WORKING INSIDE.

a. All . rimar conductor con-nection bolts should betor ued to recommendedvalues. (An alternative toretorttuing tnay be use ofinfrared heat sensor (thermo-graphic) techniques. Theseprocedures are specialized,however, and require plans toovercome loading and safetydifficulties.) See below.

b. 'ighten all secondary controlwire connections while check-ing for loose lug crimps andbroken wire strands.

HOT JOINT MAINTENANCE - For primary joints which show evidence of excessiveheat: I) Open joint and inspect connection surfaces. (2) If surfaces appear reasonablysmooth, with only minor pitting or corrosion, clean and dress contact surfaces minimizingremoval of plating. (3) If surfaces are heavily pitted or corroded, or if there has beenany melting of conductor material, the affected parts must be replaced. (4) Replacecontact Qnger springs if breaker disconnects have been exposed to excessive heat. (5)Contact surfaces should be protected with NO-OX-ID before re-assembly. (6) Userecommended torque values in tightening bolted connections. (7) Before and aftermillivoltdrop testing can provide some confidence that the problem has been corrected.

JOINT COVERS - During surveillance it may be necessary to remove joint covers. It ispossible that the cover may crack when it is Qexed for removal or replacement due toembrittlement from loss of plasticizer. An isolated incidence of such cracking indicatesthat the joint has been operating at higher temperatures than normal. A cracked covershould not be reused. An embrittled cover which has not cracked will provide insulatingcapability at least as long as it took to embrittle. Generalized embrittlement of jointcovers is not expected for twenty years or more.

MS 3.2.1.9-1

Page 6

~-

CIRCUIT BREAKER SERVICING

Circuit breakers require inspection andservicing periodically to assure operabil-ity. Servicing should be accomplishedbased on number of operations since lastserviced, with an elapsed time limit.The appropriate frequency of servicingdepends on the duty of the circuit br'eak-er. As experience warrants, the recom-mended frequency of servicing shownbelow should be adjusted on specificbreakers. to account for more/less severeduty than initiallyexpected, based on thebreaker condition when serviced.~ *

Recommended service frequency isshown for. three general - categories ofduty:

LOAD CURRENT SWITCHING UPTO RATED CONTINUOUS CUR-RENT . ENVIRONMENT NORMALMINIMALCONTAMINATION.

Service breaker every five (5) yearsor upon accumulating the numberof operations shown below sincelast serviced, whichever comesfirst.

5HK-250, 7.5HK-500, 15HK-500/750 - 2000 operations.

5HK-350, 15HK-1000 - 1000operations.

MOTOR START CAPACITOR 8c

REACTOR SWAMI'CHING OR ANYDUTY IN A CONTAMINATED EN-VIRONMENT.

Service breaker every two years orupon accumulating the number ofoperations shown below since lastserviced, whichever comes first.

5HK-250, 7;5HK-500, 15HK-500/750 - 750 operations.

5HK-350, 1 5HK-1000 - 400operations.

FAULTINTERRUPTION

Service a breaker which has inter-rupted short circuit current as soonas possible.

This service program qualifies a circuitbreaker for the total number of opera-tions shown below before replacement orfactory refurbishment is required. Thelimit is suggested to provide margin.

,5HK-250, 7.5HK-500, 15HK-500/750, Total Operations - 10,000,Suggested Limit- 9,000.

5HK-350, 15HK-1000, TotalOperations - 5,000, Suggested Limit- 4,500.

The foQowing should be accomplished ateach service interval:

CLEAN INSPECT 8c LUBRICATEPRIMARY DISCONNECTS.

CONTACT 8c INSULATIONCLEANING.

PUFFER CHECK.

ARC CHUTE INSPECTION

OPERATION CHECK

CONTACT PRESSURE CHECKS%

MILLIVOLTDROP TEST

Instructions follow which clarify the„above.

MS 3.2.1.9-1

Page 7

In addition, the hardware (bolts; nuts,screws and pin retainers) should bechecked with a thorough inspection to besure that they are in place and secure.There are other adjustments which maybe required due to the operating or testabnormalities below:

TIMING TEST+

Should be run before and after thebridge pivot pressure adjustment(below). Recommended as a perti-nent periodic test to evaluatebreaker condition.-

CONTACT PRESSURE ADJUST-MENT*+

Required if contact pressure checkindicates a problem.

BRIDGE PIVOT PRESSUREADJUSTMENT+*

Required when the millivolt droptest is above limits (pressure toolow - resistance too high.)

RACKING MECHANISM ADJUST-MENT++

LUBRICATION

The HK circuit breakers are lubricatedduring factory assembly as follows:

All mating "'surfaces of moving cur-rent-carrying joints have beenlubricated with NO-OX-ID SpecialGrade "A" grease.

All other mechanism parts, bear-ings, pins, etc. have been lubricatedwith ANDEROL"757.

The circuit breaker mechanism 'does not- ordinarily require lubrication in the usual

moderate service environment expect-ed. However, ~ if operating difficultiesare. experienced, if grease becomes con-

: taminated or if parts are replaced, relub-rication with ANDFROL grease may berequired. Contact the nearest BrownBoveri Electric district office for fieldassistance or fac tory refurbishingarrangements.

Primary disconnect Qngers should becleaneg with — a solvent approved byNIOSH or local'uthority, inspected forcorrosion or evidence of arcing andrelubricated with NO-OX-ID grease ateach servicing.

Required if interlock fails to blockclosing while breaker is being rack-ed in or out or racking latch is notblocked with breaker closed.

NOTES:

Do not use NO-OX-ID grease on arcingcontact parting surfaces.

LATCH CHECK SWITCHADJUSTMENT++

Do 'ot use light oil to lubricatemechanism parts.

Required if circuit breaker fails tolatch closed on reclosing.

The spring char ging motor is sealed,lubrication is not recommended.

+Specific guidance on the timing test is included in the following instructions:5HK-Z50, 350 - IB 6.Z.1.7-1, 7.5HK-500, 15HK-500/750 - IB 6.2.2.7-1 and 15HK-1000 —IB 6.2.3.7-1.

+~Consult the circuit breaker Instruction Bulletin for guidance in making thecontact pressure check and adjustments.

MS 3.2.1.9.1

Page 8

CONTACTCLEANING

AND INSU LATION CAUTION:~ FOR SAFETY KEEP CL'EAROF ALLMOVING PARTS.

Any dirt, soot or grease should beremoved from the circuit,breaker con-tacts and surface of entire currentcarrying structure, as well as all*insula-tion surfaces, with a cloth saturated withan approved solvent. Cleaning'f theinsulation is important because contam-ination can accumulate, and, withmoisture, can place the circuit breakerin jeopardy, dielectrically.

A degree of burning and pitting on thecircuit breaker arcing contacts'"is to beexpected from normal operation; onhighly inductive or capacitive circuitsand after major interruptions, some pit-ting may occur on the main contacts.When necessary to dress the contacts,cover the puffer nozzle with a cloth,then follow the contour of the contactswith a fine file. Do not attempt to elim-inate pitting entirely. After this maint-enance, the contact pressure and milli-volt drop should be checked; adjustmentshould be made, if indicated.

NOTE: Replacement of contact needonly be considered when after repeateddressing of contacts, less than 50% ofthe original contact material thickness isleft, the tips of the stationary arcingcontacts have been eroded away, or anycontact has been broken, cracked orburned through.

PUFFER CHECK

The performance of the puffers can bereadily checked during servicing. Eachpuffer should provide a moderate blast ofair at the breaker contacts, on openingof the circuit breaker. This can bedetected by holding a sheet of paper overthe top of the contacts and opening thecircuit breaker. All three poles musthave puffing action or else the circuitbreaker must not be placed in service.

ARC CHUTE INSPECTION

The arc chutes should be inspected inter-nally to insure that no breakage occuredto the liner plates. Further, there maybe a crust formed on the liner plates ifthe load current interruptions were closeto the continuous current rating of thebreaker or moderate faults were inter-rupted. This crust should be removedwith arc chutes off the breaker by care-fully using a carborundum stone orscraper. The arc chute should be blownout with dry air to remove the resultantdust and particles.

Arc plate and liner plate breakage shouldbe carefully looked for, along withexcessive erosion of the arc,plates. Thearc plates are made. of,ceramic materialand perform the function of extractingheat from the arc as it is being forcedinto and elongated by them. The leadingedges become coated with glass thatcomes to the surface from the extremeheat. A direct measure of use is theamount of ceramic surface with glassbeads evident.

When the entire leading edge andportions of the Qat arc plates are notedto be heavily encrusted with glass beads,the arc chute should be replaced. Itshould be noted that this condition willvary between arc chutes on the samebreaker because of a single-phase faultand asymmetrical current incidences. Ifthere are any questions, Brown BoveriElectric, Inc. Switchgear SystemsDivision should be consulted forrecommendations.

OPERATION CHECK

During servicing it is desireable to verifybreaker operability. It is recommendedthat this be done at the minimum

I

~, MS 3.2.1.9„.1

, Page 10

TIMING TESTj II I

After. a change in bridge pivot adjust-ment, and periodically, if a functionalcheck is desired, the closing and openingtimes should be checked by, use,of atime-travel analyz er+, oscillograph orcycle counter to monitor the time fromenergizing the control ito arcing contacttouch or part.

t

The circuit, breaker, closing and„-openingtimes should be within, the'following,timeranges for normal o'geration.

NOTES: Below QoC, the closing timeswill increase, opening times grill be with-

, in the~limits.

If„ timing is outside the 'imits, the

. factory should be.contacted for recom-m endations.

CIRCU IT BREAKER

5HK25 0, 5HK3 5 01200 Amp

5HKZSQ2000 Amp

SHK350Z000 Amp3000 Amp

7.5HKSQQ, 15HK500,15HK750

1200 Amp2000 Amp2500 Amp

15HK10001200 Amp2000 Amp3000 Amp

CLOSING TIMERANGE " MS++

50-90

60-95

50-9065-95

105-140105-140105-140

85-12585-12585-125

OPENING TIMERANGE - MS++

23-35

23-35

23-3523-35

25-4225-4225-42

25-4225-42ZS-42

With 125VDC Control, timing may vary slightly at othercontrol voltages.

*Analyzer mounting support and instructions available on special order.

MS 3.2.'f.9-1

Page 9

expected control voltage 'evel.(Typically 80% of nominal).

MILLIVOLTDROP TEST

During servicing, the resistance of -thecircuit breaker current carrying partscan be checked with a millivolt droptest. This test should be performedregardless of circuit breaker duty ornumber of operations.

The following table lists millivolt dropand resistance values for the circuitbreakers, from terminal to terminal,exclusive of the primary disconnects.

If the millivolt drop does not exceed150% of the values, shown in the table onbreakers with light loading, 'no contact

'maintenance is 'ecessary. If themillivolt drop does exceed 150% of thevalues, the main and arcing contactsshould be dressed. with a Gne file,cleaned and adjusted for proper contactpressure and then rechecked. If thevalues are still in excess of the 150%value, the bridge pivot pressure should bereadjusted.

If breaker loading is 75% or more ofrated current, it is recommended that theusted values be used as limits.

CURRENT RATINGMAXIMUMS

MV DROPSY a)MAXIMUM

MICRO-OHMS

5HK250) 5HK3501200 Amp2000 Amp

5HK3503000 Amp

7.5HK500, 15HK50015HK750

1200200025003000

977

-6

4535

20

45353530

15HK1000120020003000

1196

554530

Mi 1 1 i vol t. drop wi th 200 Amperes flowing.

~ ~ ~7

\ ~ MS 3.2,1.9-1

PGgC 11

p

N.

Alki".ASIAGROWN GOVERI

P)

ABB Power Distribution inc.4379 County Line RoadChalfont,PA 18914 Supersedes issue A

Printed in U.S.A. 1C CMC 785