ML18058A256

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Responds to Violations Noted in Insp Rept 50-255/91-19. Corrective Actions:Walkdown of Setting Sheet Specs for Motor Control Ctrs Located Inside Containment Will Be Provided
ML18058A256
Person / Time
Site: Palisades 
Issue date: 03/02/1992
From: Slade G
CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9203100042
Download: ML18058A256 (18)
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consumers Power l'OWERINli lllllCHltiAN'S* l'ROliRESS Palisades Nuclear Plant:

27780 Blue Star* Memorial Highway,_ Covert. Ml 49043.

March 2, 1992 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 GB Slade General Manager DOCKET 50-255 ~ LICENSE DPR-20 PALISADES PLANT -. REPLY TO NOTICE. OF VIOLATION AND REPLY TO NOTICE OF DEVIATION; NRC INSPECTION ~EPORT No. 91019

  • NRC Inspection Report No. 91019 provided the results of the special electrical distribution system functtonal inspection {EDSFI) of the Palisades Plant.

The inspection report identified apparent violations and deviations from NRC requirements.. ou-r response to_ the violations* and deviations is provided in the attachments to this letter. The inspection report also identified a number of.

open items and unresolved items and requested a reply to those items as well.

As was discussed with* Mr. Bruce Jorgensen of Region I II staff and Mr. Pat Donnelly of our staff, on February 12, 1992, a reply to these issues will. be provided by March 31, 1992.

With regard to the design vulnerabilities that the inspection team identified, we will consider appropriate measures to address these vulnerabilities.. With regard to the issues related to the seismic capabilities of plant equipment,

. which are being assessed under NRC Generic Letter 87-0l, we will strive to make meaningful improvements to plant nuclear safety in this area.

We are cognizant of the many other issues and concerns raised by the inspection and are pursuing resolutions to them consistent with their relative prior~ty. If yriu should so desire we.will provide a status of our efforts whenever it is mutually convenient.

~3 Gerald B Slade General Manager

  • CC Administrator, Region Ill, USNRC NRC Resident Inspector - Palisades Reply to Notice of Violation Reply to Notice of Deviation 090013 9203100042 920302 PDR ADOCK 05000255 G

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  • A CM5 ENEl?GY COMPANY.
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CONSUMERS POWER COMPANY To the best of my knowledge, information and belief, the contents of this submittal are truthful and complete.

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David_P Hoffman, Vic i_dent Nuclear Operations Sworn and subscribed to before me this ~day of*-~ 1.992.

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- Nqtary 7ubl ic My commission expires B£VERLV9'NNAVERV NOTARY PUBUC-JACKSO!fCOUNT'i. Ml MY COMMISSION EXPIRES 12-7-92

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ATTACHMENT 1 Consumers Power Company Palisades Plant Docket 50-255*

REPLY TO NOTICE OF VIOLATION INSPECTION REPORT No. 91019 March 2, 1992 10 Pages

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1 REPLY TO NOTICE OF VIOLATION Violation 1 10 CFR 50, Appendix 8, Criterion III, requires that applicable regulatory*

requirements and the. design basis be correctly translated into drawings, procedures and instructions. Criterion III. also requires that design changes be subject to design control measures conunensurate with the original design.

Contrary to the above, from March 1986 until December 13, 1991, the licensee failed to translate a design* change, which re-sized 17 thermal overloads associated with safety related motors~ into field instructions for implementing the changes.

Reason for the Violation The reason for the di~crepancies found between installed overload heaters and those specified in the setting sheets for motor control centers {MCCs) No. 1 and No. 2 was procedore inadequacy.

System Maintenante and Construction Servic~s (SM&CS), a section of the Consumers Power Company corporate. laboratory, laboratory procedure PD~11, "Test Procedure for Molded Case Circuit Breakers,"

Revision. 7-1985, used for testing of molded case circuit breakers, did not

  • require SM&CS personnel to compare installed equipment with that specified in the
  • setting sheet.

Breakers within MC Cs No. 1 and No. 2 were tested by SM&CS personnel in 1986.

Breaker testing was performed in conjunction with the plant electrical maintenance department's preventive maintenance of the breaker buckets. During the bucket preventive maintenance, the breaker.was removed from the bucket by electrical maintenance and given to SM&CS for testing.

Upon complet.ion of testing, the breaker was returned to the plant electrical maintenance department for reinstallation in the bucket.

In 1986, SM&CS personnel were not.explicitly required by the SM&CS procedure (P0.,11) to verify that the settings of protective devices listed on the setting sheet (e.g., starters, bre~kers, overload heaters, etc.) matched those installed in the bucket.

Based on information provided by SM&CS personnel who performed the breaker testing in 1986, the verification of

. protective devices listed on the setting sheets was considered an SM&CS responsibility. However, this verification ~as apparently not performed in this instance. Furthermore, Syste~ Protection Engineering did not provide the revised setting sheets to the plant.

In 1986, the method by which the plant would have been notified of an equipment discrepancy was through a deficiency notice generated by SM&CS personnel during breaker testing. No deficiency notices have been lotated for MCCs No. 1 and No. 2 from 1986 testing. Thus, plant personnel were* not aware of the equipment discrepancies. Absence of the deficiency. notices.

also supports the belief that a comparison between installed and required equipment was not performed.

2 Additional means now exist tri prevent i*nstalled equipment from going unnoticed and unchanged from that specified in the setting sheet. Upon issuance of setting or equipment changes by System Protection Engineering, the pl ant Systems Engineering Department receives an information copy of the revised setting sheet which notes any changes~ This serves to notify the plant of changes in overload

  • heater sizing and allows for these changes to be made via the work order process prior to SM&CS personnel coming onsite to test the device.

Corrective Actions Taken and Results Achfeved L Provide walkdown verification of setting sheet specifications for MCCs located inside containment.

For. Safety Related MCCs operability determinations will be made for discrepant information.

2~ All MCCs located outside of containment h*ve been walked down for component v~rification.

  • These results will be utilized to imple~ent actions to ensure plant equipment matches the setting sheet specifications. For Safety Rel~ted MCCs operability determinations will be made for discrepant ~nformation.

Corrective Action to*A~oid Future Non-Compliance The procedure for the testing of molded case circuit breakers, PD-11,. "Test

. Procedure for Molded Case Circuit Breakers, 11 was revised in 1989 to explicitly require SM&CS personnel to.verify.that installed protective devices (e.g.,.

breakers, starters, overload *heaters, etc.) match those specified by the setting sheet.

(This require*ment exists in the 1991 revision of the procedure.). The.

verification rt:?quirement should prevent equipment discrepancies from being overlooked* during future breaker testing.

Date of Full Compliance Full ~ompliance will be achieved with replacement of thermal overload heate~s or when revision to setting sheets has been made. This is ~urrently sch~duled for completion by June 1992.

Violation 2 10 CFR 50, Appendix 8, Criterion XI, requires that a test program be established to assure that al 1 testing required to demonstrat_e that systems and components wi71 perform satisfactorily in service is identified and performed in accordance with written test procedures.

Contrary to the above:

a. - Prior to December 13; 1991, the licensee failed to establish a program to periodically test the ability of each safety related battery charger to deliver rated output current and supply a1.1

~equired loads* following a design basis accident (OBA).

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3 Reason for Violation 2a

  • The reason for this violation is that we failed to recognize the need to develop a program to periodically test the capacity of the battery char~ers.

Technical specifications section 3.7 basis states: "Each battery has two battery chargers available rated at 200. amperes each.

Except for the first minute following a OBA,* the capacity of the two battery chargers will handle all required loads." However, technical specifications section 4~7 does not contain a requirement for testing the battery charger capacity.

During battery surveillance testing, the battery chargers typically operate at or near their maximum current rating for the battery equalizing portion of the test.

  • While these tests do not include any. acceptance criteria for charger performance,. they do provide. a means for detecting charger performance degradation.

Corrective Actions Taken and Results Achieved No immediate actions has been taken.

Corrective Actio~ to Avoid future Non-Complfance Develop ar:id implement a test program that periodically verif1es that the battery*

chargers will provide rated o~tput current for an appropriate period~of ti~e.

Procurement of test equipment and development of a test procedure i~ required."

Date of Full Compliance An outage wi 11 be required to test the battery chargers for rated output current, Preliminary plans are to procure equipment, develop a test procedure, and conduct

  • the capacity test by the end of the.1993 Refueling Outage.

Violation 2b 10 CFR 50, Appendix 8, Criterion XI, requires.that a test program be established to assure that. a77 testing required to demonstrate that systems and components will perform satisfactorily in service is identified and performed in accordance with written test procedures.

. Contrary to the above:

b.

Prior to December 13, 1991, *the licensee failed to satisfactorily demonstrate in post modification testing, the* proper operation of the control functions associated with contacts 3/3C, 4/4C, 5/5C, and 11/llC located on hand switch HS-152-106RLTS.

4 Basis for Disputing Violation-2b FollOwing the EDSFI exit meeting 'On December*'13,-*I991; an in'"depth review of the documentation package for facility change.,(FC} 687, "Add.Local/Remote Transfer Sw.itch to Breaker 152-106," was performed.

Completed test procedure T-FC-687-001, "Testing,of New Fuses and Remote/Local Transfer Switch 'for Breaker>152*-*106, II which was comp 1 eted in 1987-,. *indicates that the contacts identified in the apparent violation were properly:tested.~:Jherefore, we***believe*a,.V:iolation does

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not exist. The documentation packageAor,.. FC~687 ts..avail~ble for revi.ew at your

  • convenience.*

The vi o 1 ati on states that co.ntacts*:,J/3c,\\:ll/l:lc,<4/4c;... and:.:25/Sc':.. on~'hand:*switch HS-152-106RLTS were not verified-in.the.post modifi*cation test.- -However, a review of the working copy of the-test-procedure indicates that contacts 3/3c*and 11/llc were verified to.operate properly.in *both the open and.closed position and contacts 4/4e and 5/5c were verifi~d in*the~closed position. -Contact 3/3c,was.

verified.in the open position in Step 5~12 o'f*"the*1)rocedure*and verified in the closed position in step 5.40 of the procedure.

Contact 11/llc was *verified in the open position in Step 5.27**of-*the* procedure*~and *'verified *in--the ***closed pas it ion in step 5. 29 of the pr-0cedure... ;.. The work i*ng -copy of* the.test; procedure *

  • shows that the procedure steps whi,ch.,.~c;:_.:;pmpJjshed.:the vet-tf.i.cation.wer:e completed on October 25, 1987.
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Contacts 4/4c and 5/5c were.. verj.fied clO"sed*_;n-step 5.35. -_This.step.checked 'for_....,

loss of indications on the meters-.'-*""*Th*es*e*.... cotitatts**we*re"*n*ot**verifi*ed,*ap*en**;n~the' "*:""'*'*.,. *.

. procedure as th.is. position results..in.. the... meters... receiving... required.power and current. Pl ant operators. l oak at these meters* on a daily-basis and through their observations have repeatedly* veri.f:~ ed.*.';t~-~t Jhe :c;pnta~t.s ~.are*:;,open.

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ViOlation 2c 10 CFR so, Appendix 8, Crit.ei'fon"XI;.. :requ'fre*i!'hat"a'test**program'"be.:estabHshed to assure that a 77 testing *reqLiirec:t>to demonstratff.: that. systems -and components wi 11 perform sati sfactori 1Y.4:mservi::c,e..ds,=:identi:ffed;~and.perf.ormed. '.in.:,accordance with written test procedu.res..

Contrary to the above:

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Although required-:::bf-:*'mod.iffo.atd.on,~.-1C-839,* colilp1et<</,_,.fn. 1989,.-..the 1 icensee failed to. test whe..ther.the. low suction pressure and lcw lube oil pressure trips were bJ.o-cked.wherc~;ch.ar:gi.ng.,,pump.. .8.".:was.: fed from. the alternate power supply.

  • s Reason for Viol~tton 2c The reason for the inadequate post modification test procedure w~s an incomplete post modification test procedure.

Review of the facility change (FC) package for FC-839, "Modify -480V Power Sources to provide. feed to P-SSB from either lC or 10 Bus," was performed.

It was determined that there were no. steps in the mod ifi cation test procedure (T-FC-839-1) that directly checked whether the low suction pressure and the low lube oil pressure trips tin chafging pump P-SSC were blocked from tripping the p~

SSC breaker when this breaker was used to power charging pump P-SSB.

Blocking of the low lube oil pressure trip for this condition (P-SSC breaker powering P~

SSB) was checked indirectly by T-FC-839-1 in that P-SSB successfully ran when powered from the P-SSC breaker.

Since P-SSC was not running at this time, it

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would have had a low lube oil pressure trip signal initiated whi~h was blocked*

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from tripping the P-SSC breaker. Howeveri rio check (either direct or indirect)

.. of the block of the low suction press~re trip was performed.

Corrective Actions Taken and Results Achieved Engineering guideline~ have been developed.to

~ugment the administrat~ve procedure for facility changes (AP 9; 03).

The admi ni strati ve procedure. and engineering_ guidelines assure that (1) appropriate testing has been specified, (2) test boundaries are well defined and -(3) justification has been provided for any portiori of the system not being tested.

The following tests will be.performed to complete the negative.logic testing:

  • i. *.With P-SSB running on P-SSC power source, simulate a low lube oil pressure and 1 ow suction pressure trip of the norma 1 source *P-SSB contact to show that they will not trip the pump.

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With P~SSB running on its normal source:

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Simulate a trip of the same abo~e coritacts and show that they will trip the pump;

b.

Simulate a trip of the other set of low fobe oil pressure and -low suction pressure trip contacts to sho~ that they will not trip the pump.

A sampling of recent modifications will be reviewed to verify that app.ropriate

  • testing was pefformed on previous electrical modifications.

The review should.

verify that both positive and negative logic testing was performed. If testing was incomplete~ further remedial action will be proposed for retesting.

W~ will also determine if fufther review of modifications testing is appropriate.

  • Corrective Action to Avoid Future Non-Compliance With the changes made to AP 9.03 and appropriate corrective action in place, no further actions are necessary.

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6 Date of Full Compliance Full compliance wi 11 be ach i eve'd with the completion of the _testing described

- abo~e, whi~h is scheduled for September 1992.

Violation 2d 10 CFR 50, Appendix EJ, Criterion XI, requires that a test program be established to assure that a 17 testing required to demonstrate that systems and components wi77 perform satisfactorily in service is identified and performed in accordance with written test procedures.

Contrary to the above:

-d.

Prior to December 13, 1991, the monthly emergency diesel generator test method failed to demonstrate the ability of the diesel generators to accept loads within the required time.

Reason for Violation 2d Failure to account for relay actuation times when d:etermining adequacy -of emergency.diesel generators start timei Techhical Specifi~ation 4.7.l.a states th~t "Each diesel generator shall be manually started each month and demonstrated to be r_eady for loading within 10 seconds. - The signal initiated-to start tlie dies-el shall be varied from one test_ to another to verify that A and B starting circuits are operable. The generator shall be synchronized from the control room and lOaded to 2400 +/- 100 KW". II

. Palisades has cons.istently interpreted this requirement as pertaining to: the

  • .*ri ability of the diesel engine to atce l erate the generator and the voltage regulator to flash the field such that the breaker closure permissives are met within 10 seconds~

DISCUSSION OF DESIGN AND TESTING PRACTICE For a diesel generator to automatically start and be ready to accept load at Palisades, a series of relay actuations must occur. Following the diesel engine start and the buildup of generator voltage, additional relay aCtuations must occur for the diesel to take on load.

Finally, the diesel generator output breaker must close for the diesel generator to be synchronized to provide po~er:

Bus undervoltage relays sense and actuate

  • Diesel generator start relays actuate Engine Start relays actuate
  • Cranking Relays actuate

~ Air Solenoid Valves actuate and open The ehgine cranks and fires.

The generator field flashes for voltage buildup.

  • Diesel Generator Voltage Check relays sense and actuate

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    • Power Failure Relays Actuate
  • Diesel generator output breaker closes
  • As. dis~ussed in* the EDSFI inspection report, our

~urrent testing method determines the time from actuation of the air solenoid valves until the time that the generator* voltage check relay flags drop.

We do not* time upstream or downstream relay act1,1ation times, nor is th-is time accounted for in the a~ceptance criteria of the surveillance test~ However, the accident analysis does make allowances for a 1 second signal processing delay, in addition to the allowed 10 second starting time for the diesel generators.

DISCUSSION OF INCLUSION OF RELAY DELAYS IN DIESEL GENERATOR STARTING TIME It is appropriate from a technical point of view to include signal processing delays either in the start time measurement of the diesel generators or in the accident analysis. The original purchase specification for our diesel generators required that the equipment supplied by the diesel generator vendor be capable of accelerating and exciting the voltage. regulator to* allow loading within 10 seconds. Therefore, it is not appropriate to add actuation of other devices in to the 10 second starting time; however, these delays should be acco.unted for in the accident analysis. The original basis for the assumed 1 second delay was established by analysis associated with the core.2 reload (late 1970s) and on the plant desjgnat that time. The.auto start logic for the diesel generators has..

changed significantly, however; the basis for the 1 s,cond assumption has never been revised. Furthermore, no confirmatory tests,or analysis have been performed to validate the assumptions. Such an effort is warranted and will b~ undertaken.

The equipment supplied by the diesel generator vendor includes the engine start relays (ESRl, ESR2), the cranking relays (CRl, CR2), the engine and generator, and the generator voltage check re.lays ( 1270-1).

It is appropriate to verify that the actuation of all these components such that the diesel generator is ready for loading ~ithin 10 secoQds.

Howev~r, as stated previously, our cur~ent testing methodology does not test the performance of the engine start relays or the cranking rel~ys.

Prior to Reiision 25 of technical specifications surveillance procedure (TSSP) M0-7A-l and Revision 26 of TSSP M0-7A-2, the testing methodology was to time from actuation of the manual control switch until 2000 volts was reached as indicated by panel meters. The above revisions to the TSSPs redefined the start time as the time from actuation of the manual control switch until the flags dropped on the.generator voltage check relays.

(This methodology still included ESR and CR actuation times.)

These changes were incorporated in response to lengthening start* times.

However, due to problems associated with beginning the start time measurement in the control room and ending the start tin:ie by observation of indication at the diesel generator, minor revisions were made to the TSSPs. These minor revisions initiated the start tim~

with actuation of the air solenoid valve at the diesel generator which effectively removed measurement of ESR and CR relay actuation time from the start time.

However, the document a ti on associated with the TSSP change did not consider this fact.

It is appropriate, therefore, to either reduce th' survei 11 ance.test start time acceptance criteria by an amount equal to ESR and CR actuation times or to change the method of obtaining start times to account for these relay actuation times..

DISCUSS ION OF. THt.:(J5[ *OF*: STOPWATCH In the di scuss*ion: of*.-the -violationtthe NRC stated'that *the.. use *of a stop watch for determining. *start tim~~--offers.:the :potential. for. additional errors. -While this is a tr~e statement, *we believe that use Qf a stopwatch is 'an acceptabl~

practice. ** Discuss.ions with other* personne 1 'throughout the fndustry*'!indtcated that many plants *utilize a stop watch to determine diesel generator start times.

We believe that:,the*errors*in~uced by human*reactH>n-at*the beginning and at the end of the timing cycle will tend to cancel each other, resulting.in reasonable assurance thatthe resul~ing starting times are representative~ *lastly, use of a stop watch tla:s *'t)een'1defi!rmiiied 't'o -be "an "acceptable *practice *1n***the '*testfr:ig :of valve stroke *Umes,<ln.;*.the ::*ASME~-*section ::X:f:*test:ing*:,program.

Corrective Actions* Taken **-and **Results* Achieved Operability of--the 'Di"esel ::Generators was -addressed 'by*:a *special* PRC team *whid1 independently verified concl usjons about* equipment operability. *'Therefore, *rio

  • other immediate actions were *necessary. *.

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Corrective Act*ion**-to,Avoid Future'*Non-Compliance

  • L Conduct a validated test or analysis which verifies that the collective non-diesel generator.:component. actuation.times,.,( bus._undervoltage: sensing relay through di es~l... gene.r.ator.,.,start. reJ..ays ;.plus... gen.erator voltage. penni ss*i ve*...

through **breaker *'*cT"O'sed~'to*'"thei"bti's')':*.. are'"*1 e*ss*'°tllaii *--o*r"'*eqffa'l '*~tb'*"the *1

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assumed in the,accident. analysis. :°Cons.:iderati0n will..,be given to.the.. need *

  • for periodic 'testing** of' this~*parameter.. **'This~corre.ctive.. action-0*:w;11** be completed d~y,.;-J..ulje',~J,::~19.92.
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Revise. the.. :monttlly **rssPs lor* the<diese*1 gen~eratbr *to "account;. for:* the actuation tfmes*~~for tlie

  • ESR"'and-CR* *rEfl ays ~*"::This' *correcti ve":aclion' 'will~ be completed by ;August<'!", *,1992.
  • Date of Full Compliance

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Violation 3

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10 CFR 50, Appendix.8,.-Cri.terdon,XVJ;~:requ.ir.e-s that measures;be::.established to assure that. condi.fi ons.aaverse.tJJ ijiJa 7.ity.:-ar.e.prompt7 y identi.ffe'd-and*corrected.

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Contrary to ihe*:above~ -~a,s:*of *December.;.JJ,~*::-"1991 ;,,i.-he<I.icensee,,fa.Hed :to; *.idenHf,-:;.,... ::*::,_~.. -.,...

and imp1ement..adequate*:eorrect.Jve.--.ac.t4*on..ftJ*"each':Of:t-he*d:hree*.fnstances:;On*,Where the Technical *..specification 1.imit of 75.0.. ~amps.. w,as.. ~xceeded.during.:diesel*.

generator surv,eiLlan<;.e.:J~s.t.L.f!:g...

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Reason for the Violation After ~ach of the overcurrent~vents a corrective actipn document was initiated, evaluated and corrective action assigned. In each case the corrective action was commensurate with the available knowledge of the situation being addressed.

Evaluation of the September 1990. event determined that the diesel generator was being operated with abnormally high current for the real load being carried before the overcurrent condition existed. With diesel generator current already being high, it was judged that only a small*

change in grid voltage was enough to cause the overcurrent. Since there

~as n~ reactive load indication, the corrective actidn was to administratively limit output current in relation to real load so that

-the generator was being operated well below the Technical Specification limit.

  • After the December 1990 event, a suspected cause of ~xceeding 750 amps

_was corrected with the* cleaning of the automatic voltage regulator

Testing in February 1991 indicated that the voltage regulator responded properly to changes in the off~site power transformer tap changer position. At that.time it was concluded that the root cause of exceeding 750 amps had been found and corrected..

Evaluation*of the September 1991 event resulted.in a more probable root cause.

Interim corrective attion has been implemented to further

  • administratively limit diesel generator output current and to prov1de additional operator training.

. Further corrective action has *been identified,_ but not yet implemented. The testing identified as a result of this evaluation requires an outage to be performed and the needed engineering evaluation requires updating of the computer model. Updating of the engineering evaluation is scheduled for completion in June 1992.

Based on the intermittent occurrence of the overcurrent condition and.the lack of identifiable causes found by _testing, the corrective action taken was appropriate for each event.

Corrective Actions Taken and Results Achieved The overcurrent condition identified in the violation results from operating-the diesel generator in parallel with the off-site po~er transformer.

This.

overcurrent condition does not occur when the diesel generator is operated in the synchronous mode.

Since the diesel generator would normally operate in the*

synchronous mode in the event of a diesel generator actuation, the safety function of the di es el generator is not compromised and would be capable of fulfilling its design function.

As a result of the Diesel Generator 1-1 trip on September 17, 1991, previous

-corrective action documents associated with overcurrent anomalies on the diesel generator were reviewed. Extensive evaluation of the effect on diesel generator electrical equipment was performed and showed no defective equipment.

In addition, computer mode 11 i ng was emp 1 oyed. to study the 2400V system during

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. several postulated conditions when Diesel Generator 1-1 was interconnected to Safeguards Transformer 1-1. The results of the computer modelling indicated that even with administrative 1 imits on the diesel generator phase current, the possibility of ~n overcurrent situation due to ~ARS still ~xists;.

We have concluded that the September 17, 1991 corrective action document adequately addresses the concerns regarding diesel generator testing and no further evaluation is necessary.

Corrective Action to Avoid Future Non-Compliance An engineering eva 1 uat ion wi 11 be performed to al low manua 1 operation of the 1~1 Safeguards Transformer tap changer during parallel operation with the dtesel

  • generator. The voltage d~ciop on each diesel generator will be measured during*.

testing which will be conducted June 30, 1992.

It is our intent to request a change to Technical Specification 4.7.ld.to provide clarific~tiori. -This change request will be submitted on a priority consistent with other:planned changes to the Technical Specifications.

Date of Full Compliance Full compliance for testing and analysis will. be achieved by June 30, 1992~

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ATTACHMENT 2.

Consumers Power Company Palis~des Plant Docket 50-255 REPLY TO NOTICE OF DEVIATION INSPECTION REPORT No. ~lOii March 2, 1992 4 Pages

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1 REPLY* TO~ NOT-JC£. :OF DEVIATION Deviation I*

FSAR Section 8:4.1.3.states that e*ach-emergency diese1 *generator~*'(iDGfhas"two * "'**,.*.-=**

separate independent starting mo.tors and to assure re1iabi1i.ty, each EDG has two independent start circuits -on *separate '*de.sources.

Contrary to the above, on December :JJ, 1991, 'tM teani identified that t.he start circuits were not independent since~a--'lo-ss*of**the**"B" --start circuit or'. loss -of the. field f1 ashing unit would. pr:e.vent.:the2::*eme~ency-:>diese.1 ":-..g.ener.ator:. from starting within the required 10 seconds.

Reason for the Deviation The current description of the diesel generator start-circuits contained in the

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  • FSAR is the same as it was when*the**original-FSARwas**developed~***The*words*used.

are ambiguous in that they may be--int-erpreted-to-lnean-,tliat*_:.the.-starting circuits.... *::.*~~-.*,*

are identical and redundant. ActualJy,,.the.~tar:ting circ;:uits. are redundant o_nl.Y....

to* the* degree that* they wi l1 both *properly engage and disengage --the "a 1 r start motors. However, they differ.significantly in that the.B start c;:ircuit provides*

field fl ashing while t_he A start. circuit :*provides* aclarm-:-and *;trip ~Juncttons {*but not field flashing*.

_*The original purchase specification'~'for**the::diesel... generator requi~ed dual electric control circuits only for.::th~ ~air *,.start: motors.

  • The--diesel engine supplier provided two start ci.rcuits ~as a*.s~i,mpl_e**method--o*f,j~nhancing -reli jibi 1-ity

-bY assuring that an engine would *'*be able to** crank ff *one* of the*' DC supply breakers failed. Channel (c'ircuit)"'separation 'i's':mainta-ined*through separation

  • and redundancy of the two :start,:*ctr-cuits'" assoctated with Diese 1 Generator '"l-1.

with respect to the two.starLctr.cu.i.ts.. associ ated.,wi.th.. DJesel.. Generator.,J ~2..

Pa 1 i sades has made a practi'ce *of:.'*cori's*.fde:r:ing\\iidi:.esei.:gen*e.r.ator*':lnoperable':::tf**one.

of the start circuits is failed. *:./However~':*:we: :have.*performed *:an* analysis as.sociated with a corrective,action\\documenL(f.'."'.PAl~9l:--OZ.5) :which,.determined that a diesel generator is capable*of.per,for:ining its*:.safety*.function should start circuit A fail.

The analys*i s -for*--th~' start--:ctrcuif A *failure**.. was* **performed in.

  • response to an inadequate e*1 ectric:a:t* des*tgn.-o.fi.:the'.annunc-iati.ori
  • ass'Ottated:*with the start circuit A.*
  • There are no requirements *in any:aes-ign basiS,document '(e.g.; IEEE:~standard~,

Reg. Guides, etc.) whi ch--reqtitre,-*separate.;and'*"redundant"*,start **circuits :*for a.

diesel generator.

The i nformat-ion ;:;in,~,question:,_:was:.,included: 0i-n-;,"the -SSAR" as descriptive material only.

Corrective Actions Taken and Result~ *:Achieved

  • No immediate corrective act.ion A.s.. pr:oposed.
        • .*\\'.:.*

2 Corrective Action to Avoid Future Non-Compliance The FSAR w*ill be revised to clarify the intent of the statement on independent start circuits.

Date of Full Compliance Full compliance will be achie~ed with a revi$ion to the FSAR.

Deviation 2 FSAR Section 8.4.1.3 states that each Diesel Generator {DG) *is provided with a remote "Control Switch Not in Automatic" alarm in the control room.

Contrary to the above, as of December 13, 1991, with the diesel generator remote/local transfer switch in "Local," there was no alarm indication in the control room to notify the operator *that. the capability of the diesel generator to start automatically is defeated.

Reason for Deviation The reasons for this deviation are:

  • Misinterpretation.of information
  • exchanged between the NRC and CPCo during evaluation of SEP topic VIII-2.

Failure to adequately implement an NRC commitment via SFC-80-128 and SFC-80-129..

  • Inappropriate inclusion of the statement in the FSAR.

Failure to explicitly consider the requirements of IEEE 279-71, Reg.

Guide 1.47, and Branch Technical Position (BTP)-PSB-2 during the d~stgn and implementation of FC-639.

Through the Systematic Evaluation Process (SEP) we committed to the requirements of IEEE 279-1971, Reg. Guide 1;47, and BTB-PSB-2 with fespect to indication of conditions which cause a diesel generator to be unable to answer an automatic demand.

The current d~sign only marginally meets these requirement~.

This design basis, which we have committed to in the FSAR, Section 8.1, is paraphrased below from BTP-PSB~2:

2.1. Deliberately induced bypass or inoperabi1ity status for EDGs should.be automatically indicated in the. control room for conditions which are expected to occur mor~ frequently than once per year. For conditions expected to occur less frequently than once per year, manual indication is considered adequate.

2.2 All status indication should be sufficiently precise to prevent

3 misinterpretation. Further, disabling or bypass indicators-should be separate from non-disabling indicators. The alarms.should be displayed both 1oca11y at the EDG and.in the control room, wfth wording that indicates that the EDG is incapable of automatically responding to a demand.

ADEQUACY OF EXISTING DESIGN The existing design does not*explicitly conform to the requirements of the existing licensing design basis. Conditions exist which may render the diesel generator incapable of responding to an automatic demand and are not annunciated in the control room.* This Condition exists (1) when HS-G20/Remote/Local Transfer Switch (RLTS) *or HS-152-107/RLTS is in the "local" position and (2) may ~xist when the voltage regulator switch is in the "manual" position. Furthermore, the

. existe~ce of the "Engine Ready" indicating light ~bove the control room engine start/stop control switch may provide confusing information to operators.und~r certain.conditions.:

The design of the RLTS was accepted by the NRC via an SER conducted for FC-639, "Install Isolation Switches on IC Engineered Safeguards Sus and l~l DG," dated

. _January* 29,.1986.

In addition, BTP-PSB-2 indicates that manually induced.

i ndi cation is adequate for di ese 1-generator unit bypass or i noperabil ity status for those conditions expected to occur less frequently than once per year..

Operation of the* RLTS is such a condition.

The switches are periodically (currently every three years) tested by Special Test T~2ao. Furthermore, since the purpose of the RL TS is to isolate critical equipment from fire damaged equipment (the control room in this case), it is not logical from a design

.perspective.to have an alarm annunciated in a location which is being isolated.

Positiohing of HS-G-20/RLTS in the "local" position will result in loss of the "Engine Ready," "Engine Running," and."Engine Crankihg" indicating lights in the control room. * (These are located above the control room control switch for*

Diesel Generator 1-1.) This provides basic indication o~mis-positionihg of the coritrol switch. Similarly, positionihg of~S-152-107/RLTS in~he local position results in the' loss of the diesel generator output bre~ker (152-107) open and closed.indication in the control room.

Placement of the voltage regulator hand switch in the manual position_may make the diesel generator unable to automatically respond to an automatic demand. *The_

position of the voltage regulator A~tomatic/Manual c6ntrol switch is indicated by lights in the control room *at the switch on *Control room panel C-04, not by alarm as suggested by the licensing design basis.

The "Erigine Ready" light above the control switch located on control room panel C-04 may provide confusing information to operators under certain* circumstances. *

  • If the engine was to trip due to generator differential action or overcurrent, both the breaker trip ~nd start signal blocked alarms would annunciate; however, the "Engine Ready" light would remain illuminated. Similarly, if the engine was

. to trip on overcrank, the fail to start and start signal blocked alarms would anriunciate; ho~ever; the "Engine Ready" light would remain illuminated.

Finally, if control power was lost to start circuit B, the start.signal blocked alarm.would annunciate in the control room; however, the "Engine Ready" light

,.::.~.

-~.

1..:*.

4*

would remain illuminated. Convetsely, if DC power was lost to start circuit A, the start signal blocked alarm would annunciate, and the "Engine Running" light would not be illuminated; however, the ~ngine would be capable of responding automatically.

These conditions may provide the operations staff with c.onflicting and confusing information which does not comply with the licensing design basis.*

Corrective Actions Taken and Results Achieved No immediate corrective action is proposed.*

    • Corrective Action to Avoid Future Non-Compliance L

Complete a review of all diesel generator process parameters, ind.ication and alarms to determine the necessity for modifications~

This review will explicitly consid~r the issu~s identified in this evaluation. *This action will be completed by May 15, 1992

2.

Perform testing and/or analysis to determine if the di ese 1 generator is.

capable of responding to an autoinatic demand with the voltage regulat9r

  • switch in the.manual* position and/or the unit-parallel switch in the parallel position. This activity will be completed by May 15, 1992.-.
  • 3.
  • We will initiate modifications* resulting from the above evaluations by August 15, 1992.

Implementation of any proposed modifications will occur through the normal modification planning process.

. 4. If additional *testing is necessary, it will. be performed during the 1993 refueling outage.

. Date 6f Full Compli~n~e Full compliance. will be achieved upon completion of modifications identified

. above.

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