ML19318C301
| ML19318C301 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 06/27/1980 |
| From: | Herbein J METROPOLITAN EDISON CO. |
| To: | Reid R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE), Office of Nuclear Reactor Regulation |
| References | |
| TLL-291, NUDOCS 8007010326 | |
| Download: ML19318C301 (3) | |
Text
Metropolien Edism1 Comoany e
J Post Office Box 480 Middletown, Pennsylvania 17057 717 9444041 Writer's Direct Dial Number June 27, 1980 TLL 291 Office of Inspection and Enforcement Attn:
R. W. Reid, Chief Operating Reactors Branch No. 4 U. S. Nuclear Regulatory Commission Washington, D.C.
20555
Dear Sir:
Three Mile Island Nuclear Station, Unit I (TMI-1)
Operating License No. DPR-50 Docket No. 50-289 Degraded Grid This letter is in response to questions raised during a telephone conference call between Messrs. J. Torcivia of GPUSC, D. Mitchell of Met-Ed, C. Cleveland of EGG, and D. DiIanni of your staff, which occurred on June 5, 1980.
The purpose of the conference call was for Mr. Cleveland to request additional information required for his review of the TMI-I Degraded Grid issue and request Met-Ed supply the NRC with a written response to the questions asked.
Question 1:
What is the logic schemc *or the Under Voltage Relays (UVR)?
RESPONSE
See attachment.
Question 2:
What is the set point variance of the relays and do the relays meet the standards of IEEE 279?
RESPONSE
Based on available data, the UVR have a + 1% variance. The specified settings are to be considered as tentative and subject to review af ter the vendor has submitted the qualif-ication report. Tentative information indicates that all UVR meet IEEE 279 standards.
Question 3:
Do all the regulating transformers function throughout the expected swing levels?
RESPONSE
The installed regulating transformers allow for an incoming voltage variance of i 15% of nominal voltage.
/dLC)/ 5I S
8007010~3 %
Metrcpc:. tan Ec: son Company is a Memcer cf the General Pubic Utmties System
a R. W. Reid TLL 291 Question 4:
What is the voltage drop fr.
the bus to the motor? Will-the motor be able to start?
RESPONSE
~ The largest voltage drop calculated.for the 460 volt rotors is 4.84 volts or 1.06% drop. All other voltage drops are 1%
or less. These levels will prevent the motors from starting.
As stated during the conference call, Met-Ed will submit a revised Technical Specification Change Request No. 60, based on verification of the new information, by August 29, 1980.
Sincerely, J. G. Herbein Vice President TMI-I JGH:DGM: hah Attachment cc:
- 7. Dilanni B. J. Snyder J. T. Collins B. H. Grier H. Silver 1
v v
-y
Attachm:nt I TLL.n DEGRADED GRID VOLTAGE SIMPLIFIED LOGIC First Level Loss of Off-Second Level Site Power Alarm Only 27-1 27-2 27-3 D/G BKR 27-4 59-1 (1)
(1)
(1)
Open (2)
(3)
And And And Any 2 of 3 Logic (4)
Or f
And Time Delay Short TimeDelakec.nj
% 1.5 Sec Lo S10 Notes:
Or
- 1) Setting N 3610V.
- 2) Setting s 2912V.
- 3) Setting N 4400V.
(4) If one relay taken out of service, logic reverts to any 1 of remaining 2.
Or o
Trip Bus Initiate Loadshedding Start D/G Undervoltage Or Overvoltage Alarm