ML20195H785
| ML20195H785 | |
| 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-87-136, TXX-88065, NUDOCS 8801200351 | |
| Download: ML20195H785 (2) | |
Text
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I MEE Log # TXX-88065 2
File # 10110
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January 11, 1988 V
- 5. Nuclear Regulatory Commission Attn:
Document Control Desk Washington, D.C.
20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION DOCKET NOS. 50-445 AND 50-446 MOTOR CONTROL CENTER SPACE HEATERS SDAR:
CP-87-136 (FINAL REPORT)
Gentlemen:
On December 30, 1987, we verbally notified you of a potentially reportable electrical separation deficiency involving the space heaters for Class 1E motor control centers. After further evaluation, we have concluded the issue is reportable under the provisions of 10CFR50.55(e).
The required information follows.
DESCRIPTION The space heaters for the Class 1E motor control centers (MCCs) are not qualified Class 1E but are connected to a Class 1E power source in the MCCs.
Aiso, the Class 1E shunt trips for the MCCs at the service water intake structure are connected as part of the non-Class 1E space heater circuit.
As a result of these configurations, the wiring of the space heaters and the shunt trips do not meet the separation requirements described in the CPSES FSAR.
The deficiency resulted because the vendor did not provide qualified space heaters and the shunt trip wiring for the MCCs was erroneously wired as part of the heater circuits.
The deficiency is limited to MCCs.
SAFETY IMPLICATIONS The absence of qualified components (space heaters) or isolation devices between the space heaters and shunt trip could permit a fault in the non-Class IE equipment / circuits to degrade the safety-related MCC circuits.
These conditions represent a significant deficiency in final design as approved and released for construction such that the design does not conform to the criteria and bases stated in the FSAR.
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o TXX-88065 January 11, 1988 Page 2 of 2 CORRECTIVE ACTION To resolve this deficiency, the following corrective actions will be taken:
1)
The two fuses in each non-Class IE space heater circuit for all Class IE HCCs will be removed.
2)
When the Class IE MCCs are de-energized, temporary power will be connected to the space heater circuits.
3)
The shunt trip circuit will be rewired to accommodate a direct power supply from the Class lE source.
These activities will be completed no later than June 15, 1988.
To preclude recurrence of this condition, separation criteria have been defined in Design Basis Document DBD-EE-57, "Separation Criteria." A reinspection of safety-related electrical equipment is being implemented under the Post Construction Hardware Validation (PCHV) Program via TVM-EE/ME/IC/CS-088, entitled "PCliV Program for Engineering Reverification of Electrical Separation."
Very truly yours,
/
if W. G. Counsil WJH/grr c-Mr. R. D. Martin, Region IV Resident inspectors, CPSES (3) 1