ML19250A105
| ML19250A105 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 03/07/1975 |
| From: | Stello V Office of Nuclear Reactor Regulation |
| To: | Goller K Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19250A102 | List: |
| References | |
| NUDOCS 7910160609 | |
| Download: ML19250A105 (2) | |
Text
'
UNITED STATES
'UCLEAR REGULATORY COMMIL.s W ASHIN GTON, D.
C.
20555 MAR i IWl5 Docket No.
50-289 K. Goller, Assistant Director for Operating Reactors, NRR TECHilICAL ASSISTANCE REQUEST fi0. 1288 Plant Name:
Three Mile Island, Unit 1 Docket Number:
50-289(License fiumber DPR-50)
Responsible Branch: OP3-3
Contact:
D. Jaffe Technical Review Branch:
EI&CS Branch Requested Completion Date:
February 28, 1975 Description of Request:
Three !'ile Island 1 - Spray Pump Motors Slow Starting Characteristics The Electrical, Instrumentation and Control Systems Branch has reviewed TAR Number 1288, requested in the memorandum from K. R. Goller on December 2, 1974, to F. Schroeder.
The results of the review are included in the enclosure.
The additional analysis and calculations demonstrate the ability of the reactor building spray pump notors to perform their intended
{',
function with a degraded offsite power supply, therefore we find these motors acceptable.
f/ a 4 d K { n Victor Stello, Jr., Ass'istant Director for Reactor ' Safety Division of Technical Review Office of Nuclear Reactor Regulation
Enclosure:
As stated above cc w/o encl:
P. Mcdonald, OPS cc w/ encl:
S. Hanauer, DRTA F. Schroeder, TR A. Giambusso, RL
'S. Varga, RL R. Bernero, LMFBR T. Ippolito, EICS j4Qg 151 D. Tondi, EICS I
C. Miller, EICS
,'**e do-E. Marinos, EICS
$ (;(pmy)g G. Lear (3
{D.Jaffe sphy 19101e odo7 p
>>,a.s
$UMMARY OF REPORT O
On September 13 and September 30, 1974 Metropolitan Edison Company submitted by letter additional analysis and calculations to support their contention of acceptability of the reactor building spray pump motors for its Three Mile Islan. Nuclear Station Unit 1.
The licensee has stated that the assumptions made for the calculations meet the conditions specified for analysis in our letter of July 26, 1974, for a degraded offsite power supply.
With minimum voltage conditions at the site, 95.6% of nominal 230 kV and maximum impedance conditions it has been demonstrated that the subject motors will start and accelerate within 6.5 seconds with 84.80% of nominal 4160V bus voltage or 88.19% on motor base.
The design specifications for these motors called for acceleration times, from rest to operating speeds (loaded) within six seconds with supply vol tage at motor terminals as low as 80% of rated.
A previous report submitted by letter, Metropolitan Edison Company to A. Schwencer da ted May 14, 1974, had documented the successful starting tests of the motors on the diesel-generators with acceleration times of less than 6.0 seconds.
SUMMARY
OF STAFF'S EVALUATI0'1 b
We have reviewed the results of the aralysis and tests reported by the licensee on May 14, 1974 and the additional calculations reported on September 13 and September 30, 1974, and have concluded that the reactor building spray pump motors are capable of performing their intended function under the most degraded power supply conditions postulated by the licensee.
The minimum voltage condition at the Three Mile Island site was assumed to be 95.6% of nominal 230 kV, which resulted in a 88.195 voltage, on motor base, at. the motor terminals.
For this condition the maximum motor acceleratior, time is 6.5 seconds, insignificantly higher than the time proposed in the design specifications, with no effect in the ESF sequence.
The design specifications called for acceleration times within 6 seconds.
Based on the conservative assumption of simultaneous loss of lines and off-system generating units which support the 230 kV at Three Mile Island, and the licensee's intention not to allow operation with such a decraded power system, as it has not allowed in the past, we find the reactor building spray pump motors ceceptable.
1408 552 O
epa
,