ML20101S536

Forwards Revised Pages to 841228 Response to Generic Ltr 84-15 Re Diesel Generator Reliability Data.Revised List of Failures & Causes of Failures for Each Diesel Generator for Last 20 & 100 Demands Encl

ML20101S536
Person / Time
Site:	Fort Calhoun
Issue date:	01/28/1985
From:	Andrews R OMAHA PUBLIC POWER DISTRICT
To:	Eisenhut D Office of Nuclear Reactor Regulation
References
GL-84-15, LIC-85-030, LIC-85-30, TAC-55860, NUDOCS 8502050481
Download: ML20101S536 (5)

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Omaha Public Power District 1623 Hamey Omaha, Nebraska 68102 402/536-4000 January 28, 1985 -

LIC-85-030 Mr. Darrell G. Eisenhut, Director Office of Nuclear Reactor Regulation Division of Licensing U. S. Nuclear Regulatory Commission Washington, DC 20555

References:

() Docket No. 50-285

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, NRC Generic Letter 84-15 dated July 2, 1984 (3) Letter OPPD (R. L. Andrews) to NRC (D. G. Eisenhut) dated December 28, 1984 (LIC-84-413)

Dear Mr. Eisenhut:

Diesel Generator Reliability Generic Letter 84-15 Reference (3) provided the Omaha Public Power District's response to Generic Letter 84-15 (Reference 2). This response stated that certain information was still under review and that if any information was altered as a result of that review, those changes would be submitted.

The District has completed the review of the Reference 3 submittal. Accordingly,

please find attached under oath or af firmation, revised pages to our December 28, 1984 submittal. Changes from the original are denoted by vertical lines in the right hand margin.

I Sincerely, 85020 PDR A 1[h$5 PDR R. L. Andrews P Division Manager Nuclear Production RLA/DJM/dao Attachment cc: LeBoeuf, Lamb, Leiby & MacRae 1333 New Hampshire Avenue, N.W.

Washington, DC 20036 Mr. E. G. Tourigny, NRC Project Manager Mr. L. A. Yandell, NRC Senior Resident Inspector 6

B 455 24 Employment w:th Equal Opportunity i Male! Female i

.4 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION In the Matter of )

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Omaha Public Power District ) Docket No. 50-285 (Fort Calhoun Station, )

Unit No. 1) )

AFFIDAVIT R. L. Andrews, being duly sworn, hereby deposes and says that he is Division Manager - Nuclear Production of the Omaha Public Power District; that he is duly authorized to sign and file with the Nuclear Regulatory Commission the attached revised pages to the District's original Generic Letter 84-15 re-sponse LIC-84-413 dated December 28, 1984; that he is familiar with the content thereof; and that the matters set forth therein are true and correct to the best of his knowledge, information and belief.

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R. L. Andrews Division Manager Wuclear Production STATE OF NEBRASKA)

) ss COUNTY OF DOUGLAS)

Subscribed and sworn to before me, a Notary Public in and for the State of Nebraska on this Jhr day of January, 1985.

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4 Generic Letter 84-15 Enclosure 2 Diesel Generator Reliability Data NRC Request - Reliability Data Licensees are requested to report the reliability of each diesel generator at the plant for its last 20 and 100 demands. This should include the number of failures in the last 20 and 100 valid demands indicating the time history for these failures. Licensees are requested to indicate whether they maintain a record which itemizes the demands and failures experienced by each diesel gen-erator unit, in the manner outlined in Regulatory Guide 1.108, Position C.3.a., for each diesel generator unit. Licensees should also indicate whe-ther a yearly data report is maintained for each diesel generator's reliabil-i ty . The criteria for detemining the reliability of diesel generators is as follows:

a. Valid demands and-failures are to be determined in accordance with the recommendations of Regulatory Guide 1.108, Position C.2.e.

b. The reliability of each diesel generator will be calculated based on the number of failures in the last 100 valid demands."

District Response The District compiled a listing of the operating history for the diesel gen-erators at Fort Calhoun. This listing was compiled in accordance with Regu- l latory Guide 1.108, Position C.2.e, with the following interpretations:

1. A valid successful run was one in which the diesel was loaded to great-er than 50% rated load for 40 minutes or more, and at the end of the run was shut down voluntarily, not to avoid damage due to a component fail ure.

. 2. Failure to meet the 10 second start criteria was not considered a fail-ure unless the engine did not start at all.

3. Failure to start on primary or secondary air followed by a successful start on the ' alternate air system was not considered a failure.

4. If a failed component was identified during routine inspection and re-paired before a start was attempted, no failure was reported.

Data prior to 1977 were not included because operating procedures at that time did not require running the diesels more than 15 minutes. This produced misleading infomation for that time period which did not accurately reflect reliability history.

The District believes that the infomation is accurate based on the infoma-tion researched. . The District had as its primary goal the determination of whether additional effort to improve reliability was required. Some judge-ment was required on older and less complete records. However, the District believed that additional review would not alter these reliability numbers significantly. Attachment 3 provides the District's plans for improving reliability.

(Revised 1/28/85)

The reliability, utilizing criteria of Regulatory Guide 1.108 and the above stated deviations, figures yielded are approximately 90.4% for DG-1 (85 suc-cesses in 94 attempts) and approximately 91.6% for DG-2 (87 successes in 95 attempts). For the last 20 demands, the reliability was 90% for DG-1 and 90%

for DG-2. The attachment to this enclosure summarizes the time history and cause of the failures.

The District does not at this time maintain a record in the manner outlined in Regulatory Guide 1.108, Position C.3.a. which itemized the demands and failures experienced by each diesel generator unit. At the present time a yearly report of each diesel generator's reliability is not maintained.

Upgrades to our methods of recordkeeping are under consideration and are discussed further in Enclosure 3.

(Revised 1/28/85)

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DIESEL GENERATOR FAILURES DG-1 CAUSE 06/16/78 100 Amp Fuse Failure 07/05/78 Generator Exciter Malfunction 07/07/78 Exciter Control Malfunction 08/09/78 Exciter Control Malfunction 03/09/79 Start Pushbutton Failure 02/21/80 Air Intake Plugged 11/05/80 Relay Contact Stuck 11/11/83 Exciter Control &

Speed Sensor Controls Malfunction 07/11/84 Governor Malfunction DG-1 Valid Tests 94 Failures 9 Two Failures in the Last 20 DG-2 CAUSE 11/16/78 Breaker Failure 01/22/80 Zener Diode Failure 01/22/80 Radiator Tube Leak 04/23/80 Start Relay Failure 03/24/82 Coolant Leak 05/19/82 Pushbutton Failure 01/18/83 Priming Pump / Governor Malfunction 09/21/83 Exciter Control Malfunction DG-2 Vatfd Tests 95 Failures 8 Two Failures in the Last 20

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Attachment to Enclosure 2 (Revised 1/18/85)