ML19241B547
| ML19241B547 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 06/06/1979 |
| From: | Lainas G Office of Nuclear Reactor Regulation |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7907180905 | |
| Download: ML19241B547 (3) | |
Text
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NUCLEAR REGULATORY COMMISSION C
WASHINGTON, D. C. 20555 3 '-
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f JUN 41979 MEMORANDUM FOR:
R. Reid, Chief, Operating Reactors Branch #4, Division of Operating Reactors FROM:
G. Lainas, Chief, Plant Systems Branch, Division of Operating Reactors
SUBJECT:
CRYSTAL RIVER UNIT N0. 3 REQUEST FOR ADDITIONAL INFORMATION FOR DEGRADED GRID VOLTAGE (TAC 10017)
Plant Name: Crystal River Nuclear Power Plant, Unit No. 3 Docket No.: 50-302 Responsible Branch: ORB #4 Project Manager:
C. Nelson Reviewing Branch: Plant Systems Branch Status : Awai. ting Information f
In response to technical assistance request TAC 10017 the Plant Systems Branch has reviewed the licensee's submittal of July 25, 1977 and found that additional information is required in order to complete our review.
The attached request for additional information should be fomarded to the licensee as soo. as possible.
(fad G. Lainas, Chief Plant Systems Branch Division of Operating Reactors
Contact:
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Enclosure:
As stated cc w/ enclosure See next page 70 0718 0 fd5 p/c no
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V. Stello D. Eisenhut R. Vollmer B. Grimes W. Russell G. Lainas C. Nelson D. Tondi P. Shemaaski S. Rhow 3
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REQUEST FOR ADDITIONAL INFORMATION CRYSTAL RIVER UNIT N0. 3 DEGRADED GUD VOLTAGE (TAC K0i7)
Based upon a review of your submittal of July 21, 1977, we conclude that the use of existing undervoltage relaying to protect against a sustained degraded grid condition is not acceptable.
1.
In attachment 1 of Mr. Stolz's letter of June 6,1977 it is stated that a second level of undervoltage protection is required.
The setpoints of this second level of undervoltage protection must protect the safety related equipment, including but not limited to, the motors, busses, contac-tors, and control circuits from a sustained low voltage condition.
The undervoltage protection must assure that a voltage below that needed to start and ac.celerate motors, pull in contactors, cr blow control circuit fuses is not present on the bus when this equipment is call upon, Provide your response to the above position.
2.
Your proposed setooint, 2375V for the 4160V bus, is far below the voltage required to start and accelerate safety related motors, close in contactors, and could pos.sibly blow control circuit fuses. A second set of under-s altage relays, in addition to the loss-of-voltage relays, are required to sense the degradad conditior.
It should be noted that these relays rust meet the requiremen; of IEEE 279-1971 including that they be seismically qualified, Class IE q -"'ied, and documented as such.
Provide your response to the above p s t'on.
3.
The chosen voltage setpoint and time delay associated with second level undervoltage protection must assure that the safety related equipment is not subjected to a voltage below that recommended by the manufacturer for a period of time long enough to cause pennanent damage.
Provide your response to the above position.
4.
Please furnish with your proposal any analysis or calculations to substantiate your choice. This may include voltage profiles of safety busses in the minimum and maximun loaded conditions, mator heat curves, contactor drop-out and pull-in voltages, control circuit fuse characteristics,
logic diagrams to show your choice of coincident logic, or schematics 9f relaying circuits.
Refer to Mr. Stolz's letter of June 6,1977 and attachments for full criteria.
5.
Accordingly, your submittal for Technical Specification Change No. 6 is not in compliance with our position as stated in Mr. Stolz's letter, namely the proposed setpoints and limits for undervoltage orotection.
Provide revised proposed technical specification changes.
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