ML20195H301
| ML20195H301 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 01/11/1988 |
| From: | Counsil W TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| CP-88-11, TXX-88070, NUDOCS 8801190220 | |
| Download: ML20195H301 (2) | |
Text
e-summmmmmmmes
==
"" 9 Log # TXX-88070
=_
File # 10110 C
908.3 R'I10CFR50.55(e) 18/ ELECTRIC Uf,"',Sd%,U.,
January 11, 1988 U. S. Nuclear Regulatory Commission Attn:
Document Control Desk Washington, D.C.
20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION 00CKr.T NOS. 50 t45 AND 50-446 BATitRY CHARGER OVERHEATING SDAR: CP-88-11 (INTERIM REPORT)
Gentlemen:
We are hereby reporting a significant deficiency) involving battery charger overheating under the provisions of 10CFR50.55(e.
The required information follows.
DESCRIPTION Battery charger BCIEDl-1 and BCIE01-2 overheated during preoperational testing. Charger BCIED1-1 tripped the 480V ac input breaker I hour following test initiation and again 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.and 47 minutes after resetting the breaker.
Station Battery BTIEDI wn then transferred from charger BCIEDI-l to charger BC1EDl-2 for recharging.
During recharging, BCIE01-2 entered the "current limiting state" accompanied by a pungent odor of overheated electrical insulation.
The battery charger operating manual (provided by the manufacturer, Power Conversion Products, Inc.), specifies that the units are self-cooled and o)erate up to a maximum ambient temperature of 50 degrees C (122 degrees F).
T1e preoperational testing was performed at an ambient room temperature of 102 degrees F (39 degrees C), well below the specified upper limit.
This deficiency was caused by the failure of the battery charger manufacturer to supply chargers in accordance with the applicable specification requirements.
This deficiency affects all 3attery chargers in safety related applications supplied by Power Conversion Products, p@o' na":888s maans
,S DCD
i TXX-88070 January 11, 1988 Page 2 of 2 SAFETY IMPLICATIONS Loss of these battery chargers would result in the discharge of battery BTIE01 af ter approximately)4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, resulting in the loss of the 125V de switchboard IED1 (CP1-EPSWED-01 and battery back-up to all the Class 1E equipment associated with switchboard 1E01.
This issue represents a significant deviation from performance specifications, such that the chargers cannot operate properly to meet the requirements and bases stated within the FSAR.
j CORRECTIVE ACTION The design criteria for battery charger ambient temperature requirements have been documented in Design Basis Document DBD-EE-044, "DC Power System".
In addition, a test was performed utilizing a temporary fan during charger operation.
The effective result was a 27 degrees F operating temperature reduction from 150 degrees F to 123 degrees F and the unit operated continuously.
Therefore, to achieve the proper charger operation, the installation of pennanent fans or other cooling means will be coordinated with the battery charger vendor. Other chargers supplied by the same vendor on both Unit 1 and i
Unit 2 will be evaluated to determine if the same problem exists.
A schedule for the completion of these corrective actions will be provided in our next report.
Our next report on this issue will be submitted no later than April 26, 1988.
very truly yours, f
V1 W W. G. Counsil WJH/grr i'
c - Mr. R. D. Hartin, Region IV Resident inspectors, CPSES (3) b I
k
-