ML20033A630
| ML20033A630 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 11/18/1981 |
| From: | Morisi A BOSTON EDISON CO. |
| To: | Ippolito T Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20033A631 | List: |
| References | |
| 81-268, NUDOCS 8111250642 | |
| Download: ML20033A630 (3) | |
Text
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FecAbm BDETON EDISDN COMPANY g#
GENERAL OFFIcts 500 SovLaTom svarET 90STON. MAmeACMUSETTE D2199 A. V. M O Rt al NUCLEAR OPERATI E SU F"f*:2RT DEPARTM ENT November 18,1981 Ltr. #81268 191
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^&y Mr. Thomas A. Ippolito, Chief D
80 Q^/
s, Operating Reactors Branch #2 -
Division of Licensing g, % pg1
/ A *~y' Office of Nuclear Reactor Regulation
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U.S. Nuclear Regulatory Comission R
Washington, D. C.
20555 01 x
No. DPR-35 Docket No. 50-293 RPS Power Supply Protective Circuitry Referen as:
A.
NRC (NRR) Letter to GE (Safety and Licensing Operation) da.ted February 23, 1979 B.
BECo Letter #80-297 dated November 26, 1980 C.
BECo Letter #81-134 dated June 17, 1981 D.
GE Letter to BECo dated August 31, 1981 E.
GE Letter to BECo dated October 16, 1981 F.
NRC Letter to BECo dated September 1,1981 The purpose of this letter is to provide an update of the schedule for the instal-lation of the design modifications to the RPS Power Supply at Pilgrim Nuclear Power Station.
As we discussed dring our telephone call of September 25, 1981, Boston Edison Companj received notification from the General Electric Company on September 21, 1981, that they were unable to meet their comm? tted hardware shipment date of September 30, 1981 (Ref. C), GE is currently awaiting the resolution of some component procurement difficulties, primarily the delivery of circuit breakers, D/I anct the environmental qualification of the unit.
j Ref. D indicates that General Electric has proceeded with conditional qualifica-tion. Boston Edison has not, however, received a qualification test report from
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GE as of this date.
We have also not been supplied with a list of recomended spare parts, or a price list concerning the same. We believe that a suitable supply of spare parts is essential to assuring the dependability of this system once it is operable. The actual revised hardware shipment date cannot be confirmed at this time.
8111250642 8111'18~
PDR ADOCK 05000293 fF
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CZTON EDCON COMPANY Mr. Thomas A. Ippolito, Chief November 18, 1981 '
Page 2 Boston Edison Company is continuing the Plant Design Change process for these modifications, and shall implement those portions of the modifications which are-possible during the present refueling outage.
BECo shall test and count-the additional GE equipment upon receipt of it. Actual tie-in, and operability cannot be accomplished while the plant is ' operating; therefore, the tie-in and operational testing shall be perforced during the first planned outage of sufficient duration (8 days), which shall allow us to cut over the three RPS supplies. An outage of shorter duration could allow cutover on the basis of one supply system per short outage.
In response to the five specific requests in Reference (F) for additional information, Boston Edison provides the following:
Request Submit detailed drawings of the proposed design modification to the monitoring -
system for the RPS power supplies (11Gs and alternate source).
The drawings should include component ratings, and schematic and wiring diagrams. Detailed relay infomation may be submitted in the form of the manufacturer's Techni. cal Bulletin.
Re_syonse A satisfactory response to this request is contained in Attachment (A) of this letter.
(GE Instruction Book for EPS 914E17.4, Approved Number 3830-83-6).
Request Submit a current revision of the electrical one-line diagram of the on-site distribution system and a schematic /clementary diagram that includes the RPS power distribution buses.
R sponse J
Please refer to Attachment (B) of this letter.
(Reactor Protection System Protective Circui t Upgrade Description, NE00-24317).
Request Provide justification that proposed time delays, if any, will not result in damage to RPS system components or affect the performance of required safety functions.
Re'sponse_
Regarding the time delay on the EPA trips, the time delay of 100 +40/-0 milli-seconds in the Installation Specification 22A7731, is applicable both to the (4G sets EPA's and the alternate power source EPA's. Although the time delay is continuously adjustable from 0.1 to 3.0 seconds, the 0.1 second setting is recomrended, based on the engineering judgement that the RPS system components should not be subjected to transients outside of the normal operational voltage and frequency range for any longer than necessitated by the trip circuitry design.
De have no evidence that the 0.1 second setting causes any availability problems for the RPS sys tem components.
BO STON EDISON COMPANY Mr. Thomas A. Ippolito, Chief November 18,1981
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Regt.est Provide justification that the design modification and components will meet the A
requirements of GUC 2 and GDC 21 of 10 CFR Part 50, Appendix A.
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Response
Regarding these requirements, the system v s reviewed and approved in Ref. A.
o The applicable portion of that letter states:
The proposed modifications would provide fully-redundant Class IE protection for the Class IE systems and components powered by the
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reactor protection system power supplies and would thereby bring the overall reactor protection system design into full conformance with Criteria 2 and 21 of the General Dcsign Criteria, Institute of Electrical and Electronic Engineers Standards IEEE-279 and IEEE-379, and the applicable orovisions of our Standard Review Plan.
Request
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S Specify monitoring system over-vol tage, under-voltage, and under-frequency trip setpoints.
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Response
The Voltage trip points are + 10% nominal.
The Frequency trip point is -5%
7 nomi nal.
The NRC letter of September 1,1981 also supplied, for our consideration, model C
Technical Specifications (STS) for Electric Power Monitoring for RPS. We are, at this time, reviewing the STS for applicability to our needs.
Our initial con-
,4 sideration of the suggested T.S. indicates that, while portions may be suitable to Pilgrim, we would prefer to develop our own Technical Specifications, thereby
_3 tailoring them into accurate conformance to the plant operating situation. We shall, of course, continue to evaluate the STS as we develop our own T.S., and incorporate those portions that are appronriate.
We believe this submittal satisfactorily responds to the requests contained in your letter. Should you desire further information regarding this matter, please contact us.
n Very truly yours, y
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