United States Nuclear Regulatory Commission - Protecting People and the Environment

ACCESSION #: 9910270120


September 20, 1999

NCR-73-02, Revision 3

Document Control Desk
United States Nuclear Regulatory Commission
Washington, DC 20555
FAX (301) 816-5151

Subject: Report of a Deviation Investigation

Nuclear Logistics presents the following information in accordance with 10CFR21, Section 21.21 (a)(2), which closes the investigation of a possible deviation.

i) Information submitted by:
Mr. Aron Seiken
Nuclear Logistics Incorporated
7450 Whitehall Street
Fort Worth, TX 76118
Telephone: (817) 284-0077
Facsimile: (817) 590-0484
ii) The item with the possible deviation was a NLI DC Power Supply, P/N NLI-LGS-G-24-OV-R8018.
iii) NLI has supplied these power supplies as Class 1E components.
iv) NLI and PSE&G Hope Creek personnel concur that the power supply over voltage protection circuit actuation was caused by the electrical circuit conditions unique the remote engine control panel. The following summarizes the investigation activities:
NLI was unable to duplicate the power supply over voltage protection actuation during laboratory testing. To gain additional information regarding the behavior of the power supply, NLI personnel traveled to Public Service Electric and Gas Company Hope Creek Generating Station to witness a start-up sequence of the diesel generator.
Prior to the start-up sequence, Hope Creek personnel verified the integrity of the power supply's input and output circuits. Additionally, a reverse-bias diode was placed across the coil of the High Priority Alarm Summary relay whose actuation was suspected of creating excessive noise in the remote engine control panel. During the entire start-up sequence, very little noise was visible on the power supply DC output voltage line. Hope Creek personnel attributed the lack of electrical circuit noise in the remote engine control panel to the suppression diode, which was installed prior to the test.
v) Supporting documentation will be provided in NLI file NCR-73, which is controlled in accordance with NLI Quality Assurance Program requirements.
vi) Power supplies models with similar over voltage protection circuitry have been supplied as safety-related components to the following facilities:
1) Public Service Electric and Gas Company
a) NLI-LGS-FA-24-OV-R-8018
b) NLI-LGS-G-24-OV-R-8018
c) NLI-LGS-G-24-OV-R-8018, Version 1
d) NLI-75-PS-3111
2) Florida Power and Light
a) LI-LGS-B-28
b) NLI-LXS-C-15-R
3) Baltimore Gas and Electric
a) NLI-LJS-10-5-OV
b) NLI-LMF-28-OVMYR-3397-3
d) NLI-LXS-C-12-R
4) Omaha Public Power District
a) NLI-LJS-10-5-OV
5) Virginia Power Company
a) NLI-LUD-16-16
NOTE: None for the NLI-L series power supplies with adjustable output voltages contain over voltage protection circuitry.
vii) No NLI-L series power supply failures of a similar nature have been reported to NLI.
vii) The conclusions drawn, as presented in this document, have been discussed with the cognizant personnel at Public Service Electric and Gas Company.

Should you require clarification, or additional information, please contact Mr. Archie C. Bell or me.

Very Truly Yours,

Aron Seiken


7450 Whitehall o Fort Worth, TX 76118
Telephone (817) 284-0077 o Fax (817) 590-0484

Page Last Reviewed/Updated Monday, June 15, 2020