ML20204H653

Responds to 860724 Request for Documentation Re Use of Thermal Lag Analysis in Environ Qualification of Electrical Equipment in Plant.Thermal Analysis Will Be Performed Per Rev 3 to CENPD-255-A

ML20204H653
Person / Time
Site:	Fort Saint Vrain
Issue date:	07/31/1986
From:	Warembourg D PUBLIC SERVICE CO. OF COLORADO
To:	Berkow H Office of Nuclear Reactor Regulation
References
P-86499, TAC-42527, NUDOCS 8608080171
Download: ML20204H653 (2)

Text

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.i w Public Service- s.,*.

Company of Colorado 2420 W. 26th Avenue, Suite 1000, Denver, Colorado 80211 July 31, 1986 Fort St. Vrain Unit No. 1 P-86499 s

Director of N5 clear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Attention: Mr. H. N. Berkow, Director Standardization and Special Projects Directorate Docket No. 50-267

SUBJECT:

Thermal Lag Analysis

Dear Mr. Berkow:

In our meeting with the NRC on July 24, 1986, we were requested to document our use of thermal lag analysis in the environmental qualification of electrical equipment at FSV.

Public Service Company intends to use thermal lag analysis when it is

, necessary to demonstrate qualification using a previously performed environmental qualification test report whose peak test temperature is lower than the peak temperature resulting from the FSV accident analysis. The thermal lag analysis will be performed in accordance with Combustion Engineering document CENPD-255-A, Rev. 3, " Class 1E Qualification - Qualification of Class 1E Electrical Equipment,"

dated October, 1985. This document was accepted for use by an NRC letter from C.0. Thomas of the NRC to A.E. Sherer of Combustion Engineering, dated August 13, 1985.

Each time a thermal lag analysis is used, the details of the calculation will be included in the EQ binder. In addition, the five self-imposed restrictions which are given in CENPD-255-A, Rev. 3, regarding application of the thermal lag analysis, are addressed each time the analysis is used.

8608080171 860731 PDR ADOCK 05000267 P PDR h\Q

P-86499

,. Page 2 July 31, 1986 We hope this letter clarifies the use of the thermal lag analysis in the FSV environmental qualification program.

If you have questions regarding this letter, please contact Mr. M. H. Holmes at (303) 480-6960.

Very truly yours, A 0 F Y / Yo m O

• D. W. Warembourg, q Manager Nuclear Engineering Division DWW/RB:pa i

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