ML19337B045
| ML19337B045 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 09/10/1980 |
| From: | Gallagher J PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| IEB-80-20, NUDOCS 8010010244 | |
| Download: ML19337B045 (3) | |
Text
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YY PHILADELPHIA ELECTRIC COMPANY 2301 MARKET STREET P.O. BOX 8699 PHILADELPHIA. PA.19101 JOSEPH W. GALLAGH ER stacinic mo"ouct o'= canntman, 12151841-5003
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September 10, 1980 IE Bulletin 80-20 Mr. Boyce H.
Grier, Director Office of Inspection and Enforcement Region I U.S.
Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406
Dear Mr. Grier:
Your letter of July 31, 1980, forwarded IE Bulletin 80-20 on " Failures of Westinghouse Type W-2 Spring Return to Neutral Control Switches".
In accordance with your request we have estimated that 65 mandays were expended in review and preparation of this response.
The actions requested by the Bulletin and our responses are listed sequentially below.
Action to be Taken by Licensees 1.
Determine whether Westinghouse Type W-2 control switches with spring return to neutral position'are used in safety-related applications at your facility.
If so, identify the safety-related systems using these switches and the total number of switches so used.
If no such switches are used in your facility, you should indicate that this is the case and ignore the remaining questions.
Response
Westinghouse Type W-2 control switches with spring return to neutral position are used at Peach Bottom, however, the neutral contacts of these switches are not used in safety-related applications on either unit in the manner described in this Bulletin.
8010910 29y
Mr. B o y c o II. Grior Page 2 Septombor 10, 1980 Twenty-two of the control switches under consideration are located on the emergency shutdown panels 20C43 and 30C43, and four are located on the local control panels for the diesel generators.
The control switches on the emergency shutdown panels are different than those described in the Bulletin in that the neutral contacts are only in the control circuits when these switches are in the " pulled out" position and operations are being made fron this location.
The following switches are located on the emergency shutdown panels:
SWITCll FUNCTION 13A-S54 RCIC Gland Seal Vacuum Tank Cond. Pump One/ Unit 13A-S55 RCIC Barometric Condsr. Vacuum Pump One/ Unit 152-1501 (E312)
Emergency Switch Gear Main Breaker One/ Unit 152-1601 (E322)
Emergency Switch Gear Main Breaker One/ Unit 152-1701 (E332)
Emergency Switch' Gear Main Breaker one/ Unit 152-1801 (E342)
Emergency Switch Gear Main Breaker One/ Unit 152-1508 (E212)
Emergency Switch Gear Main Breaker One/ Unit 152-1608 (E222)
Emergency Switch Gear Main Breaker One/ Unit 152-1708 (E232)
Emergency Switch Gear Main Breaker One/ Unit 152-1808 (E242)
Emergency Switch Gear Main Breaker One/ Unit 152-1603 Emergency Service Water Pump Transfer (20C43 Only) 152-1706 Emergency Service Water Pump Transfer (20C43 Only)
The 13A-S54 and 13A-S55 switches apply to the RCIC system.
With the switches in the normal in position.a RCIC automatic initiation signal is not effected by a failure of the neutral contacts.
If conditions existed such that an operator is operating from the emergency shutdown panel and RCIC is auto-initiated, the neutral contacts do not inhibit a RCIC auto-start.
Failure of the neutral contacts to acto-start the gland seal vacuum tank condensate pump and the barometric condenser vacuum pump does not disable the operability of the RCIC system.
In addition, the operator still has the ability to manually start both pumps.
Switches 152-1501, 1601, 1701, 1801 and switches 152-1508, 1603, 1708, 1808 apply to control of the emergency switchgear main breakers from the emergency shutdown panels.
When the 4KV transfer switches are in the normal in position, they do not effect an automatic transfer of emergency feeds nor do they interfere with an automatic startup and transfer to the diesel generators.
If conditions existed such that an operator is operating from tne emergency shutdown panel when one of the
Mr. Boyco H.
Grier Pago 3 September 10, 1980 emergency feeds is lost and the neutral contacts fail, then auto-closure of the alternate source 4KV breaker would be disabled.
Under these circumstances aa operator would be stationed at the emergency shutdown panel and manual transfer would still be operable.
Switches 152-1603 and 152-1706 transfer control of the emergency service water pumps to the shutdown panel.
Both emergency service water pumps auto-start whenever the diesel generators auto-start.
In the event that one of the emergency service water pumps is shutdown and the neutral contacts fail, the pump would not re-start.
However, under these circumstances an operator would be stationed at the emergency shutdown panel and manual start would still be operable.
When the transfer switch is in the normal in position, they do not effect an auto-start of the emergency service water pumps.
The remaining switches under consideration are the local diesel generator voltage control switches (one/ diesel).
These switches are used for manual local control only and have no effect on an emergency diesel startup from an automatic initiation signal or on control from the control room.
The neutral contacts are used to short the motor terminals of the motor driven rheostat for the voltage setpoint adjustment on the automatic voltage control.
If the neutral c o r. acts were to remain open when manually adjusting voltage, it would not cause a malfunction of the diesel or the diesel voltage regulator and would not inhibit voltage adjustments.
Voltage control from the Control Room is not affected.
It is therefore concluded that no safety-related function of any safety-related system would be disabled by the failure of a neutral contact on a Westinghouse Type'W-2 control switch at Peach Bottom.
Based on'this conclusion, the testing and corrective measures requested in the remainder of the Bulletin are not applicable.
Very truly yours, s/ h 0 Q
cc: Director Division of Reactor Operations Inspection Office of Inspection & Enforcement Washington, DC 20555