ML20077G938

Proposed Tech Specs Revising Test Frequency Requirements for Diesel Generators Identified in Tech Spec 3/4.8.1.1

ML20077G938
Person / Time
Site:	River Bend
Issue date:	06/26/1991
From:	GULF STATES UTILITIES CO.
To:
Shared Package
ML20077G937	List: ML20077G938 RBG-35251, Application for Amend to License NPF-47,revising Test Frequency Requirements for Diesel Generators Identified in Tech Spec 3/4.8.1.1
References
NUDOCS 9107030225
Download: ML20077G938 (4)

Text

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1 4

ELECTRICAL POWER SYSTEMS SURVETLLANCE REQUIREMENTS (Continued) 2.

At least once par 12 hou;s with the last reported room temperature

< 50'F.

6 h.

At least once per 10 years, or after any modifications which could affect diesel generator interdependence, by starting all three diesel generators simultaneously, during shutdown, and verifying that all three diesel generators accelerate to at least 450 rps for diesel l

generators 1A and 18 and 900 rps for diesel generator 1C in less l

than or squet) to 10 aconds.

1.

At least once per.10 years by:

1.

Drainfa,, each fuel oil storage tank, removing the accumulated sediment, and cleaning the tank using a sodium hypochlorHe or equivalent solution, and 2.

Performing a pressure test of those portions of the diciel fuel oli systes designed to Section III, subsection N0 of the ASME Code, in accordance with ASME Code section XI Article IWD-5000.

4.8.1.1.3 Reports - All diesel generator failures, valid or non-valid, shall be reported to the Commission, pursuant to Specification 6.9.2, within 30 days.

Reports of diesel generator failures shall include the information recomended l

in Regulatory Position C.3.b of Regulatory Guide 1.104, Revision 1 August 1977.

If the number of failures in the last 100 valid tests, er. : ;:r ne:1::r Mt l

, is greater than or equal to 7, the report shall be supplemented to include the additional information recommended in Regulatory Position C.3.b of Regulatory i

l Guide 1.108 Revision 1, August 1977.

of any diesel generator i

i l

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l 9107030225 910626 PDR ADOCK 03000458 P

PDR 1

RIVER SENO - UNIT 1 3/4 8-10

TABLE 4.8.1.1.2-1 OIESEL GENERATOR TEST SCHEDULE Number of Failures Number of Failures in in Last 100 Valid

_Last 20 Valid Tests

• Tests

• Test Frecuency

<1

<4 Once per 31 days 1

S Once per 7 day

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~1Criteria for determining number of failures and number of valid tests shall be in accordance with Regulatory Position C.2.e of Regulatory Guide 1.108, but determined on a per diesel generator basis.

For the purposes of determining the required test frequency, the previous test failure count may be reduced to zero if a complete diesel overhaul to like-new condition is completed, provided that'the. overhaul, including appropriate post-maintenance operation and testing, is specifically approved by the manufactu'rer and.if ' acceptable reliability has been demonstrated.

The reliability criterTon shall be the successful completion.of 14.consecu-tive tests in a single series.. Ten of these tests shall be in accordance with the routine Surveillence Requirements 4.8.1.1.2.a.4 and 4.8.1.1.2.a.5 and four tests.in accordance with the 184-day tqsting requirement of Surveill-ance Requirements 4.8.1,1.2,a.4 and 4.8.1.1.2.a.5.

If this criterion is not satisfied during the first series of tests, any alternate criterion to be used to transvalue the failure count to zero requires NRC approval.

This

• • The-cssosieted test frequency shall be maintained until seven ansecutive failure free demands have been performed and the number of fat fees in the last 20 valid demands has been reduced to one, or less f

g 9

RIVER BEND - UNIT 1 3/4 8-11 4

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ENCLOSURE II The following should be inserted as noted on page B 3/4 8-1:

Generic Letter 84-15 prescribed increasing the survejllance test frequency where previous testing indicated a reliability of less than or equal to 0.95/ demand until restored reliability was demonstrated.

It also considered a

prescriptive testing program which included seven consecutive successful demands without a failure of the DG.

1 The test frequency of Table 4.8.1.1.2-1 is based on the criteria goals of an overall reliability of > 95 % and to attain 2 90 % prior to returning to monthly testing.

There is a requirement to return to weekly testing if the number of f ailures is greater than or equal to 2 in 20 or 5 in 100.

The note to the table (footnote "**")

explains that whenever failures in excess of one in 20 or five in 100 last valid tests an accelerated test frequency must be maintained.

This weekly (accelerated) test schedule is continued until two conditions have been satisfied.

First, seven consecutive successful tests have been accumulated, and second, the failures in the most recent 20 tests have been reduced to one or less.

Seven successful tests indicate a reliability of at least 0.90/ demand.

Continuing the accelerated testing unti.

the number of failures is one or less out of 20 adds further assurance that the DG reliability has not degraded below the 0.90/ demand level.

After each failure the criteria will be reviewed for reentry into once per weekly testing.

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3/4.8 ELECTRICAL POWER SYSTEMS n

BASES 3/4.8.1, 3/4.8.2 and 3/4.8.3 A.C. SOURCES, O.C. SOURCES and ONSITE POWER DISTRIBUTION SYSTEMS The OPERABILITY of the A.C. and 0.C. power sources and associated distribution systems during operation ensures that sufficient power will be available to supply the safety related equipment required for the safe shutdown of the facility and the mitigation and control of accident condi-tions within the facility.

The minimum specified independent and redundant A.C. and 0.C. power sources and distribution systems satisfy the requirements l

of General Design Criterion 17 of Appendix "A" to 10 CFR Part 50.

L The ACTION requirements specified for the levels of degradation of the power sources' provide restriction upon continued facility operation commen-surate with the level of degradation.

The OPERABILITY of the power sources is consistent with the initial condition assumptiins of the safety analyses and is based upon maintaining OPERABLE at least Division I or II of the casite A.C. and 0.C. power sources and associated distribution systems during stcident conditions coincident with an assumed loss of offsite power and single failu'e r

of the i-r onsite A.C. or 0.C. source.

Ofvision III supplies the high pressure scre spray (HPCS) system and the standby service water pump 1SWP*P2C with its auxiliaries.

The A.C., and 0.C. source allowable out-of-service times are based on Regulatory Guide 1.93, " Availability of Electrical Power Sources," December 1974, as mod.ified by plant-sp,ocific analysis and diesel generator, manufacturer's recommendations. When diesel generator LA or 18 is ineperable, there is an edditional ACTION requirement to. verify that all required systems, subsystems, trains, enmponents and devices, that depend on the remaining OPERABLE diesel generator 1A or 18 as a source of emergency power, are also OPERABLE. This requirement is intended to provide assurance that a loss of offsite power, during the period that diesel generator 1A cr 1B is inoperable, will not result j

in a complat: loss of safsty function of critical systems. The term verity, as used in this context, means to administrative 1y check, by examining logs or other information, to determine if certain components are out of service for rainta-nance or other reasons.

It does not mean to perform the surveillance require-ments needed tu demonstrate the OPERABILITY of the component.

The OPERA 8ILITY of the minimum specified A.C. and 0.C. power sources and associated distribution systems, during shutdown and refue:ing, ensures that the facility can be maintained in the shutdown or refueling condition for extended time peri,ods and sufficient instrumentation and control capability is available for monitoring and maintaining the unit status.

The surveillance requirements, for demonstrating the OPERABILITY of the diesel generators, are in accordance with the recommendations of Regulatory Guide 1.9, " Selection of Diesel Generator Set Capacity for Standby Power Supplies," March 10, 1971, and Regulatory Guide 1.108, " Periodic Testing of Diesel Generator Units Used as Onsite Electric Power Systems at Nuclear Power Plants," Revision 1, August 1977, as modified by plant-specific analy:is and diesel generator manufacturer's recommendations.

mA RIVER BEMD - UNIT 1 8 3/4 8-1

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