ML20106F811

Safety Evaluation Supporting Amend 80 to License DPR-16

ML20106F811
Person / Time
Site:	Oyster Creek
Issue date:	02/11/1985
From:	Office of Nuclear Reactor Regulation
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ML20106F805	List: ML20106F803 ML20106F811
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Download: ML20106F811 (4)

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'o UNITED STATES sg( '[g g

NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 j

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 80 TO PROVISIONAL ~ OPERATING LICENSE NO. DPR-16 GPU NUCLEAR CORPORATION AND b E' JERSEY CENTRAL POWFR AND LIGHT COMPANY OYSTER CREEK NUCLEAR GENERATING STATION DOCKET NO. 50-219 1.0 INTPODUCTION

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J By letter dated August 11, 1980 and supplemented October 18, 1982, December'5, 1983, February 9 and March 23, 1984, GPU Nuclear Corporation (GPU)

(the licenseel requested an amendment to Provisional Operating License No. DPR-16 for.the Oyster Creek Nuclear Generating Station. This l

amendnent would add Appendix A Technical Spacifications (TS) requirements for the previously approved design of the station electric distribution system voltages.

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A Notice of Consideration of Issuance of Amendment to License and Proposed I

No Significant Hazards Consideration Determination and Opportunity for Hearing.related to the requested action was published in the Federal Register on November 21, 1984 (49 FR 45952). No request for hearing or public comments were received.

2.0 DISCUSSION.AND EVALUATION The criteria and NRC staff positions regarding degraded grid voltage protection were sent to Jersey Central Power and Light Company (JCP&L), now GPU, on August 11, 1976 and.on June 3, 1977. JCP&L responses were dated November 5, 1976, April 18, 1977 September 25,'1979 August 11,1980, and April 30, 1981.

In his letter dated August 11, '300, the licensee proposed additional plant Technical Specification requirements for the plant degraded grid voltage protection. These requirements were (1) Limiting safety system l

settings for the 4.16 KV Emergency Bus in Section 2.3,P; (2) Limiting l

Conditions for Operation for the 4.16 KV Emergency Bus, items N.a and-N.b,-

of Table 3.1.1; (3) Limiting Condition for Operatioh ~for bus' tie breakers in Section 3.7.5; and (4) Surveillance Requirements for the 4.16 KV Emergency l

Bus, items 28.a and~28.b, in Table 4.1.1 of the Technical Specifications.

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The results of this review are contained in the attached staff's Safety Evaluation.(SE) entitled ~" Degraded Grid Protection for Class 1E Power Systems.

Oyster Creek Nuclear Power Station," dated October 16, 1981; The staff concluded in'the~ October 16, 1981; SE that the licensee's p'roposed changes to the Technical Specifications were acceptable and met the NRC requirements for degraded grid protection except for the followfng issues which are discussed below: 1) a typographical error;in the licensee's proposed

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technical specifications explained in the licensee's'Merch 23,'1984 letter i

and 2) the need for limiting conditions for operation on the use of the voltage regulators on the 4.16 KV Emergency Bus.

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In the licensee's letter dated March 23, 1984, the licensee stated that the time delay for the 4.16 KV Emergency Bus.Undervoltap (degreded voltage) 4

.in Technical Specification page 2.3-3 was 10

• 10% L1.'0) second time delay.

The 10 1% (0.1-) second time delay given by the licensee in previous submittals, and reviewed in the technical evaluation by EG&G Idaho and

' approved by the staff was & typographical error. The staff has reviewed the 10 10%(1.0) second time delay and concluded that it does not change Jthe conclusion of the original evaluation that the proposed maximum time delay does not exceed the maximum time delay assumed in the FSAR analysis.

The staff acce, pts the licensee's proposed time delay.

The,0ctober 16, 1981 SE stated that under the extreme grid voltage conditions it is necessary for the voltage regulators that are presently installed at the plant distribution station to be operational in order to prevent i

some Class 1E equipment from being exposed to over/under voltage and 460 V motor starters from being exposed to voltages below the minimum continuous rating of these starters. As a result, the staff recomended the inclusion i

of limitingsconditions for operation (LCO) in the TS when the regulators are

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bypassed or under maintenance. The licensee stated in his letters dated October 18, 1982, December 5,1983, and February 9,1984, that control and operation of the voltage regulators are adequately addressed in the plant procedures and inclusion of an LCO in the TS is unnecessary and burdensome.

e The licensee stated the following as additional justification for this

. position regarding the voltage regulators.

1 The voltage analysis assumed a minimum grid voltage of 214.8 KV on the 230 KV gH d.

However, the lowest grid voltage experienced at Oyster Creek'has been 217 KV. Under the assumed minimum grid voltage of 214.8 KV the analysis showed only control rod drive (CRD) feed pumps and ' fuel pool filter pumps were sub.iected to voltages,below their minimum ratings. However, fuel pool filter pumps are not necessary for plant shutdown or cooldown and can be turned off-for extended periods of time and run only when voltage conditions permit. CRD feed pumps are important for plant operation; however, they are not needed during accident conditions and no credit is taken for these pumps for any accident analysis.

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The operators are notified by an alarm in the control room activated by overvoltage relays when an overvoltage condition exists. The over-voltage can be corrected via addition of loads or changing of the 230-345'KV.transfomers taps if regulators are unavailable.

Availability of the 34.5 KV capacitors to improve voltage levels if necessary.

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,n The voltage analysis assumed a bus loading which included all safety and nonsafety loads including all reactor feed pumps. It is very unlikely that all of these loads will run concurrently.

As discussed above, the staff concurs that CR0 feed pumps are not needed for plant safe shutdown and that these pumps are not necessary during accident conditions.

Based on the above, under h highly unlikely event that a degraded grid voltage could occur concurrent with the outage of the voltage regulators, no Class 1E equipment required for safe shutdown would be subjected to a voltage below its minimum r.ating. The present plant procedures and the use of capacitors, load tap changers and overvoltage alams are sufficient to improve voltage to Class 1E equipment. The staff concurs with tfra licensee that inclusion of the Timiting conditions for operation for the voltage regulators in the TS are unnecessary.

The proposed amendment change request supports the design of the grid undervoltage protection system, and the mode of operation of the bus. tie breakers previously approved in the October 16, 1981 SE and includes relay surveillance. requirements setpoints and limits, and LCOs. The proposed amendment meets the staff's requirements and is acceptable.

3.0 ENVIRONMENTAL CONSIDERATION

This amendment invol'es a change in the installation or use of a facility v

component located within the restricted area as defined in 10 CFR Part 20 and changes to surveillance requirements. The staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has.proviouslyJ1ssued a proposed finding that this amendment involves no significant hazards consideration and there has been no public coment on such finding. Accordingly, this amendment meets the eligibility criteria for categorical exclusion set.forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b).no environmental impact statement or environmental assessnent need be prepared in connection with the issuance of this ' amendment.

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4.0 CONCLUSION

The staff has concluded, based' on the considerations. discussed above, and in the October 16, 1981, SE that:' (1) there is reasonable assurance that the proposed manner; and (2) public will not be endangered by operation in the health and safety of the such activitics will be conducted in compliance with the Commission's regulations and the issuance of this amendment will not be inimical to the cornon defense and security or to th'e health and safety of the public.

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5.0 ACKNOWLEDGEMENT This evaluation was prepared by S. Maskell and J. Emani.

e Dated: February ll, 1985.

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Attachment

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o UNITED STATES

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NUCLEAR REGULATORY COMMISSION n

5, aI WASHINGTO N. D. C. 20555 k.,,a,/

.0ctober 16, 1951 s

Docket No. 50-219 L505-81-10-023 Mr. I.' R. Finfrock, Jr.

Vice President

'e Jersey-Central Power & Light Company a -

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Post Office Box 388 i

Forked River, New Qersey 08731

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Dear Mr. Finfrock:

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SUBJECT:

DEGRADED GP.ID PROTECTION FOR CLASS 1E POWER SYSTEMS -

OYSTER CREEK NUCLEARvGENERATING STATION y

' This letter transmits the Safety Evaluation for Degraded Grid Protection for Class 1E Power Systems. This evaluation was based on your submittals I dated November.5,1976. April 18,1977, September 25, 1979, August 11, 1980 and April 30, 19,81. We find your analysis.to be acceptable.

As a res71T of your review, you have installed voltane regulators to' minimize the possibility of degraded voltages occurring on the 1E busses-is an acceptable solution to the problem, however you must include l

the limiting conditions of operation to cover the use o.f the voltage

,. regulators in the proposed amendment to the, Technical Specifications..

i We request that you provide this information to us within 45 days of receipt of this. letter.

n Sincerely.

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Dennis M. Crutchfield, Chief Operating Reactors Branch f5 i

Division of Licensing Enc'losure:

Safety Evaluation Report w/ Attachment (EGG-EA-5476) cc w/ enclosure:

See next page e

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- October 16, 1981

- Mr. I. R. Finfrock, Jr.

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G. F. Trowbridge, Esquire Gene Fisher S. haw, Pittman,- Potts and Trowbridge Bureau Chief 1800 M Street, N..W.

Bureau of Radiation Protection

. 20036 380 Scotts Road 7

. Washington, D.

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Trenton, New Jersey 08628 J. B. Liebaman, Esquire l'

..Berlack, Israels & Lieberman.,

26 Broadway Commissioner., f New Jersey Department of Energy 101 Commerce Street New York, New York 10004 Newark, New Jersey 0710.2 s

Natural Resources Defense Council 91715tli Street, N. W.

Licensing Supervisor Oyster Creek Nuclear Generating Washington, D. C.,20006

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Station J. Knubel P. O. Box 388 BWR' Licensing Manager Forked River, New Jersey 08731 GPU Nuclear Resident Inspector 100'Interplace Parkway c/o U. S. NRC P.arsippany, New Jersey 070.54 P. O. Box 445 Deputy Attorney G'eneral Forked River, New Jersey.08731 State of Tew Jersey Department of' Law and Public Safety 35 West State Street - CN 112 '

Trenton, New Jersey 08625 Ocean County Library Brick Township Branch 401 Chambers Bridge Road Brick Town, New Jersey 08723 Mayor Lacey Township 818 Lacey Road Forked River, New Jersey 08731 Commissioner Department of'Public Utilities State of New Jersey 101 Commerce Street Newark, New Jersey 07102 U. S. Environmental Protection Agency Region II Office ATTN: Regional Radiation Representative 26 Federal Plaza New York, New York 10007 e

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SAFETY EVALUATION OYSTER CREEK NUCLEAR POWER STATION UNIT 1

. DOCKET NO.50 <219 DEGRADED GRID PROTECTION FOR CLASS 1E POWER SYSTEMS

' INTRODUCTION AND

SUMMARY

Ques' tion', criteria'5nd daff positions regarding degraded grid voltage protection s

were sent to Gersey Central Power and Light Company (JCP&L) on August 11, 1976 r*

and on June 3,1977. Their responses were dated November 5,'1976; April 18,

.u 1977; September 25, 1979;- August 11, 1980; and' April 30, 1981. EG&G Idaho urider" contract to NRC performed a detailed review and technical evaluation of th'e submittals. The results of thi's " review are contained in EG8G's Technical Eval'uation Report (TER) entitled'" Degraded Grid Protection for Class 1E Power Systems, Dyster Creek Nuclear Power Station Unit 1," dated August 1981 and

attachedtothisrepoirt. We have reviewed the TER and, except' for two conclusions, concur with the findings.

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' DISCUSSION The voltage analysis performed by the licensee over the range of normal grid

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voltages showed that without system modification, voltages below the pick-up rating of certain-460 volt starters and less than the minimum operating

.value of two motors could occur during normal low voltage excursions of the off-site gri.d. Po,ssible system modifications which could alleviate the

. degraded voltage conditions at the 1E bus'es are the following:

(1-) adding

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voltage regulators', (2) raising the second-level trip setting. (3) raising y

the voltage to affected equipment by adding new transformers, or,(4) replacing I

the affected equipment.

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Option 2 would place the trip setting of the second level volt' age protection relays on the IE. buses within the normal range of grid voltage variations.

This would violate position 3 of the NRC generic lett' r dated August' 8,'1977.

e Therefore, this option would notgacceptable.

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O-O Options 3 and 4 would correct for low grid Voltage conditions, but would not correct for oiervoltage conditions whhh may occu'r on the 1E buses during lightly-loaded grid conditions. Therefore, these options 'are less than optimum solutions.-

Optiorrl, installation of Voltage regulators, was chosen by the kicensee and, in the staff's opinion, has the advantage of correcting'the ' effects of both high 'and low grid voltage" conditions. h minor problem with this arran,gement is that the-voltage regulators will only assure acceptable 1E bus Voltages down to degraded grid vonditions o} -20%. kt -22% of' normal grid voltage, the second-level undervoltage 're. lays will actuate, causing the on-site

. generators to start. However.;between -20% and -22% of normal grid voltage, the lE bus voltage could be below the operating point of certai,n, motors and.

starters. TMs-is not considered a serious problem because in this eitremely

. degraded condition, the off-site grid will be unstable and either collapse completely, disintegrate, or cause grid load shedding. All-of these outcomes will affect the voltage of the 1E bus and lead to activation of 'the o.nsite l

generation.

We therefore concur with the licensee that the installation of voltage regulators on the 34.' Sky electrical systems'provides acceptable voltage 1,evels on the 1E buses within the cited range of grid. voltages. This meets our, regulator,y

[ position #1 and is ace'eptable. However, we require that the licensee include limiting conditions of operations in th'e proposed amendment to the technical specifications to cover situations when the regulators are'out of service.

We disagree with EG&G's conclusion in the TER whidh disallows credit for the voltage regulators because of their limited' range. As previously discussed,'

the voltage. regulators will maintain acceptable 1E bus voltages throughout the normar sustainable ranbe'of off-site grid.voltanes,and down to a degraded grid

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a level of -20% of normal. In the event grid volthges degfide further, it is the staff's opinion.that the off-sfile grid wouTd b.e. extremely unstable and would collapse, disintegrats, or initiate grid load-sh'edding., These

. results would' drop the. grid voltage further caus,ing the diesel generators to a

start at -22% of nonnal off-site voltage. The use of voltage regulators

, provides a.means of maintaining'accepta51e voltages on the.,1E tiuses. The staff concurs and gives, credit for their use at this nuclear power station.

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EVALUATION CRITERIA S..

The criteria used by EG&G in this technical evaluation of the analisis includes SDC 17 (" Electrical Power Systems") of Appendix A to 10CFR50 IEEE Standard 279-1971 (" Criteria Tor Protection Systems 'for Nuclear Power Generating Stations"), IEEE Standard 308-1974 (" Class.1E Power Systems for Nuclear Power Generating Stations"), ANSI Standard C84.1-1977 "Voitage gtings for Electrica1

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Power Systems and Equipment (60hz)", and staff positions as detailed in the generic letter'sent to th_e licens.ee on June 3,1977.

MODIFICATIONS

' As a result of the NRC request JCP&L has installed a second-level undervoltage scheme to protect safety-related equipment from a sus'tained degrade'd grid.

voltage condition. As previously discussed, the licensee has also'. installed i

, 34.5 kv voltage regulators to maintain the secondary voltage of the start-up transformers in an acceptable range.

Finally, the license.e has proposed changes to the plant's technical specifications including:' reldy surveillance requirements, setpoints and limits, and limiting conditions for operation.

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4 CONCLUSIONS 1.

We conclude that acceptable voltage and' time setpoints have been selected by the licensee.

2. :, Acceptable co, incident' logic has been employed.

I-3.

Acceptable time-delays -have been selected.

4.

Disconnection of off-site power on degradeIgrid conditions will

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be automatica11/' initiated.

5.

Voltage monitors meet IEEE standard 279-1971.

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Technical specifications \\re not complete. The -licensee's proposed amendment of technical specifications must include limiting conditions of operations when the. voltage regulators are not in use.

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INTERIM REP' ORT Accession No.

' Report No. F4f:-FA 8id76 Contract Program or Project Titly r

' Selected Operating' Reactor Issues Program (III)

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sut$ect of this Documents

. Degraded Grid Protection for Class lE Power Systems, Oyster Creek Nuclear Power Station Unit 1, Docket No. 50-219 Type of, Document:

Technical Evaluation Report v-Iuthor(s):

. D. A. Weber Cete of Document:

August 1981

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Responsible NRC Individual and NRC Office or Division:

P. C. Shemanski, Division of Licensing This document was prepared primarily for preliminary or internal use. it has not received full review and approval. Since there may be substantive changes,this document should not be considered final.

EG&G Idaho, Inc.

Idaho Falls, Idaho 83415 Prepared for the k

U.S. Nuclear Regulatory Commission O

i Washington, D.C.

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g Under DOE Contract No. DE AC07 76fD01570 6

NRC FIN No.

A6429

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'NTERIM REPORT I

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DEGRADEDGRIDPROTECTION'FORCLASSlEPOWERSYSTE$5 OYSTER CREEK NUCLEAR STATION UNIT 1 t'

Docket No. 50.219 D. A. Weber Reliability and Statistics Branch Engineering Analysis Division EG&G Idaho, Inc.~

August 1981

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TAC No. 10038

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.A'STRACT B

in June 1977, the NRC'sent all operating reactors a [ letter outlining three positions the staff had taken in regard to the onsite emergency power

-systems. Jersey Central Power & Light Company (JCPE-) was'to assess the l

susceptibility of the safety-rel' ted electrical equipment at the Oyster a

Creek Nuclear Statibn, Unit 1, to'a sustained voltage degradation of the offsite source and interaction of the offsite and cnsite emergerfcy power systems. This report contains an evaluation of JCP&L's analysis, modifica-1

'tions, and technical specification changes to comply with these NRC post-tions. The evaluation has determined'that.JCPE does not comply with one of the NRC positions.

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FOREWORD This report is supplied as part of the " Selected Operating Reactor

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Issues Program-(III)" being conducted for the U.S. Nuclear Regulatory Com-mission Office of Nuclear Reactor Regulation, Ilivision of Licensing, by EG&G Idaho, Inc., Reliability and Statistics Branch.

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The U.S. Nuclear Regulatory Commission funded the work under the authorization, BLR 20 19 01 06, FIN No. A6429.

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CONTENTS l.0 INTRODUCTION.............................:......................

1 2.0 DISIGNBASECRITERIA............................................

1 3.0. EVALUATION...........'..................'.....'...............'..... '

1 3.1 Exi sting Undervoltage, P rotection............ /.............

2 3.2 Modifications.............................................

2 3.3 Discussion.........................

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4.0 CONCLUSION

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5.0 REFERENCES

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TECHNICAL EVALUATION REPORT DEGRADED GRID PROTECTION FOR CLASS 1E POWER SYSTEMS OYSTER CREEK NUCLEAR STATION UNIT 1

1.0 INTRODUCTION

On June 2, 1977,1 the NRC requested the Jersey Central Power & Light Company (JCP&L).to assess the susceptibility of the safety,-related electri-1 cal equipment 'at the Oyster Creek Nuclear Station to a sustained voltage l

degradation of the offsi emergency power systems.je source and interaction of the.offsite and onsite i

.The letter contained three positions with which the current design of the plant was to be compared. After comparing the current design to the staff positions, JCP&L was required to either, propose modificati6hs to satisfy the positions and criteria or furnish an analysis to substantiate that the existing facility design has equivalent

, capabilities.

JCP&L responded to the'NRE letter of June 2, 1977 with a submittal 4

i dated September 25, 1979 2 i

1976,3 October 14 1976,4.NovemberThis submittal pnd submittals of Sgptember 5, 1976,3 February 1 1977 1,1979,9,anuary,o April 18,1977,7,ugust 1{.1977.8, A

November J

18 I

1980,10 August 11, 1980.1 April 30 1981 Final Safety Analysis Report (FSAR)N comp 12 and the Oyster Creek lete the information reviewed for this report.

2.0 DESIGN BASE CRITERIA The design base criteria that were applied in determining the accepta.

bility of the system modifications to protect the safety-related equipment from a sustained degradation of the offsite grid are:

1.

General Design Criterion 17 (GDC 17), " Electrical Power Nuclear Power Plants," of 10 CFR 50y9Syitems," of Appiendix A. "

IEEE Standard 279-1971, " Criteria for 2.

for Nuclear Power Generating Stations"hotection Systems

'8 IEEE Standard 308-1974, " Class IE rS 3.

Nuclear Power Generating Stations" p ' ystems for 1

4.

Staff positions as detailed in a let'ter sent to the licensee, dated June 2, 1977 5.

ANSI Standard C84.1-1977, " Voltage Ratingfor Electri-cal Power Systems and Equipment (60 Hz).

1 3.0 EVAL'UATION This section provides, in Subsection 3.1, a brief description of the existing undervoltage protection at Oyster Creek; in Subsection' 3.2, a 3

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d'escription of the licensee's proposed modifications for the second-level undervoltage protection; and in Subsection 3.3, a discussion of how the 1

proposed modifications meet the design base criteria!

l 3.1 EiistingUndervoltageProEection. For loss-of-voltage. protection, each of the safety-related 4160V buses 1C and 1D has a set of General Elec-i tric type 1AV53K under/overvoltage indication relays. The undervoltage trip setpoint for each relay is 68.8% (2864V).

Each relay will operate in l

3 seconds on tot 1 1 loss of power. The 68.8% on the 4160V buse's will result in voltage.of 317'(66%) and 297 (61.Ift) for the 480V substations and motor

' control centers (MCC's), respectively. Operation of~either relay will initiate isolation of the 4160V buses and loads, initiate load-shedding and i

start of.the emergency diesel ' generators (DG's), energizq.the emergency

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buses'with permanently connected loads and energize the automatically con-j nected emergency loads Jhrough a load sequencer.

t 3.2 Modifications. As a result of the NRC request, JCP&L has j

installed a second-level undervoltage scheme to protect safety-related l

equipment from a sustained degraded grid. The scheme consists of the addi-i tion of independent 'undervoltagewelays for buses 1C and 1D. The three i

relays on each bus are connected in a two-out-of-three coincident. logic, I

with a setpoint of 3671V +1% (36.7V) and a time delay of 10 seconds +1%

(0.1 sec). Either bus reTay logic will initiate disconnection of the off-

. site' power source whenever the voltage setpoint and time limits have been i

exceeded. With the offsite power disconnected, the existing loss-of-voltage i

relays on the emergency buses will operate as described in Section 3.1.

The.11nnsee has proposed changes to the plant's technical.specifti:N 4

tions including: relay surveillance requirements, setpoints and limits, and limiting conditions for operation.

i 3.3 Discussion. The first position of the NRC staff letterl

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re' quired that a second level of undervoltage protection for the onsite power system be'provided. The letter stipulates other criteria that the undervoltage protection must meet. Each criterion is restated below fol-I lowed by a discussion regarding the licensee's compliance with that j

cr.iterion, l '.

"The selection of voltage and time'setpoints shall be

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determined from an analysis of the voltage requirements of the safety-related lodds at all onsite. system distri-j

.bution levels.

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Thelicensee'spr'oposedsetpointof3671V(88.5%of j

4160V) results in voltages of 88.5% at the 460V rated

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motor starters. The motor starters will p.ickup at 85%

i voltage and the control circuitry can withstand a lower voltage. This setpoint allows worst case terminal volt-ages of 91.6%, 85%,.87.5% and 90.5% for the correspond-ing safety-related 4000V, 480V, 460V, and 440 motors.

The minimum rating is 90% for the 4000V motor, and 86.6% for the worst case 480V, 460V, and 440V motors 4

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(which consider a 1 15 service factor). At the pro-1

' posed setpoint all'4000V, 460V, and 440V safety-related

• equipment will operate at. voltages above the minimum required. However the -setpoitit allows the 480V motors

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and some 460V motor starters to,be operated continuously at voltages below their minimum rating. Therefore the proposed setpoint is not satisfactory.

The. licenses submittal of April 30, 198112 points out i

that.the analysis does not consider the automat!ic olieiation of newly insi:alled voltage regulators which I

will maintain the'4160V bus at 4100V uhen the ' grid is at its minimum analyzed valve. However ' credit cannot be given for the regulators since they have a Timited

+10%) and there are no' Technical voltageregulation(Tn'gConditionsforOperation(LCOs)

Specifidations Limit i

1 regarding plant operation should the regulators be bypassed or out of operation.

l 2.

"The voltage protection sh'all include' coincident logic to preclude spuri6u' trips of the offsite power s

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sources."

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The proposed modification incorporates a two-out-of-three coincident logic scheme, thereby satisfying this t

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crRerion.,

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"The time delay selected shall be based on the follow-ing conditions:

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The allowable time delay, including margin, shall not exceed the maximum time delay that is assumed in the FSAR accident analysis."

l The proposed maximum time delay of 10 seconds s

delay.'}econds) does not exceed this maximum' time

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The time delay shall minimize the effect of short.

duration disturbances from reducing the"unavaila-l bility of the offsite power so' rce(s)." -

u The licensee's proposed minimum time delay of 10 seconds is long enough to override an'y short.-

inconsequential grid disturbances and voltage dips caused from the starting of large motors..

c.

"The' allowable time duration of a' degraded voltage condition at all distribution system levels shall not result in fLilure of safety systems or compon-ents."

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A review of the licensee's voltage analysis indi-cates that the time delay will not cause any fail-ures of the safety-related eq'dipment.2 4.

"The voltage monitors shall automatically initiate the disconnection of offsite power sources whenever the voltage setpoint and t'ime-delay limits have been exceeded."

A review of the licensee's 'submittals confirms that this criterion is met,_ '

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,t 5.

The voltage monitors shall be designed -to satisfy.the requirements of IEEE Standard 279-1971."

r.

The license ^e has stated in his proposal that the modi-fications are designed to meet or exceed IEEE Stan-dard 279.

.6.

"The technical specifications sha11' include limiting conditions for operation (LCOs), surveillance require.

ments, trip setpoints with minimum and maximum limits, and allowable values for the second-level voltage pro-F *.

tection monitors."

' Tfie licensee's proposal for technical specification changes includes all the required items ftfr the second- -

. T 6el protection monitors. However,'there are no LCOs governing plant operations should the regulators be I

bypassed or out of service.

l The second NRC staff position requires that the syst'em design auto-matica11y prevent load-shedding of the emergency buses once the onsite sources are supplying power to all sequenced loads. The load-sheddin'g must also be reinstated if the onsite breakers are tripped.

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The existing undervoltage relaying scheme for the emergency ' buses already has these features incorporated. The second-level undervoltage protection will be tilocked automatically when the emergency buses are being fed from the onsite sources.

The third NRC staff position requires'that certain test requirements

. be added to the' technical specifichtions. These tasts were to_ demonstrate the full-functional operability and independence of the onsite power l

sources, and are to be performed at least once per 18 months during shu't-down. The tests are to simulate loss of.offsite power in corijunction with a safety-injection actuation signal, and to simulate interruption and sub-sequent reconrection of onsite power sources. These tests verify the proper i'

operation of the load-shed system, the load-shed bypass when the emergency diesel generators are supplying power to their respective buses, and that there is no adverse interaction between the onsite and offsite power

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sources.

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i The. testing procedu i.

intent of this position.gs proposed by the licensee comply with the full Load-shedding on offsite power trip is. tested.

Load-sequencing, once the diesel generator is supplying the safety buses.

l is tested. The time duration of the tests (equal to or greater than 5 min-utes) will verify that the tirR6 delay is sufficient to avoid spurious trips

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and that~the load-shed bypass circuit is functioning properly.

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4.0 CONCLUSION

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Based that the ins,on.the information provided by JCPE, it has been determined j

talled modifications do not comply with NRC; staff position 1.

Certain 480V motors may operate at voltages below their minimum ratings at the present second-level pndervditage relay setpoint, when the offsite grid is at its minimum analyzed, valve. Credit e.annot W given for the installed

.a voltage regulatort as the regulators provide limited regulation (+10%) and,

e there are no LCOs governing plant operations should the regula, tors be bypassed or out of ser'vice.

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The existing load-shed circuitry complies with' staff position'2 and '

i will prevent adverse inteription of the offsite and onsite emergency power systems.

The proposed changed to the technical specifications adequately test

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the system modifications and comply with staff position 3.

The surveillance requirements, limiting conditions for operation, minimum and maximum limits for the trip 16etpoint, and allowable values meet the intent of staff posi,

tion 1.

t is therefore. concluded that the setpoint of the installed second-level undervoltage relays is not acceptable. The proposed changes to the technical specifications are acceptable, except for the second-level under-voltage relay setpoint.

5.0 REFERENCES

1.

NRC letter (R. W. Reid) to JCPR, dated June 2,1977.

2.

JCPR letter (I. R. Finfrock) to the Director, Nuclear Reactor Regu-

~1ation, dated September 25, 1979.

3.

JCPR letter (I. R. Finfrock) to Mr. Geo'ge Lear, Chief, Operating r

Reactors Branch No. 3, Division of Reactor Licensing, dated September 16, 1976.

4.

JCPE letter (f. R. Finfrock) to Mr. George Lear Chief, Operating Reactors Branch No. 3, Division of Reactor Licensing, dated October 14, 1976.

5.

JCPR letter (I. R. Finfrock) to Mr. George Lear, Chief, Operating Reactors Branch No.~3, Division of Reactor Licensing, dated November 5, 1976.

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6'.

JCP&L letter (I. R. Finfrock).to Mr. George Lear, Chief, Operating Reactors Branch No. 3, Division of Reactor Licensing, dated February 1, 1977.

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7.

JCP&L Tetter (I. R. Finfrock) to Mr. 'Georg'e Lear, Chief Operating

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Reactors Branch No. 3, Division of Reactor Licensing, dated April 18, t

' 1977.

'8... JCP&L. letter (I. R. Finfrock) to Mr. George Lear Chief. Operating

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, Reactors Branch,No. 3. Division of Reactor Licensing, dated August 15, 1971.

9.

JCPR letter (I. R. Finfrock) to the Directot.of Nuc1 ear Reactor Regu-lation, dated November 1. 1979.

10.' JCP&L letter (I. R'.' Finfrock) to'the Director of Nuclear Reactor Regu-lation, dated January 18, 1980.

11. ' JCPE letter (I. R~. Finfrock) to the Airector of Nuclear Reactor Regu-

-lation,datedAugust11,198p.

12..JCP&L letter (I. R. Finfrock) to the Director of Nuclear Reactor Regu-lation, dated Aprli 30, 1981.

Final SNety Analysis Report (FSAR) for the Oyst,er Creek Nuclear 13 Station.

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14. General 0esign Criterion 17. " Electric Power Systems," of Appe'ndix A, i

" General Design Criteria for Nuclear Power Plants," to 10 CFR Part 50,

" Domestic. Licensing of Production and Utilization Facilities."

l

-15.

IEEE Standard 279-1971, " Criteria for Protection Systems for Nuclear Power Generating Stations."

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16.

IEEE Standard 308-1974, " Standard Criteria for Class IE Power Systems for Nuclear Power Generating Stations."

17. ANSI E84.1-1977, " Voltage Ratings for Electric Power Systems and Equip-ment (60Hz).".

18.. IEEE Standard 141-1976, "IEEE Recommended Practice for Electric Power Distr.ibution for Industrial Plants."

'19.

HEMA Standard, NEMA'MG1-1972, " Motors and Generators."

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