ML19246B884
| ML19246B884 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 06/06/1979 |
| From: | Lainas G Office of Nuclear Reactor Regulation |
| To: | Ippolito T Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7907180898 | |
| Download: ML19246B884 (3) | |
Text
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I pa arc oq[o UNITED STATES y, _
NUCLEAR REGULATORY COMMISSION y ^ ) *e g
WASHINGTON, D. C. 20555
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,0 JUti G1979 MEMORANDUM FOR:
T. Ippolito, Chief, Operating Reactors Branch #3, Division of Operating Reactors FROM:
G. Lainas, Chief, Plant Systems Branch, Division of Opcrating Reactors
SUBJECT:
PILGRIM UNIT NO, 1, REQUEST FOR ADDITIONAL INFORMATION FOR DEGRADED GRID VOLTAGE (TAC 10041)
Plant Name:
Pilgrim Unit No.1 Docket No.: 50-293 Responsible Branch: ORB #3 Project Manager:
J. Hannon Reviewing Branch: Plant Systems Branch Status: Awaiting Information In response to technical assistance request TAC 10041, the Plant Systems Branch has reviewed the licensee's submittal of August 24, 1977 and found that additional information is required in order to complete our review.
The attached "equest for additional information should be forwarded to the licensee as soon as possible, dc4E G. Lainas, Chief Plant Syst ms Branch Division of Operating Reactors
Contact:
S. Rhow, X28077 J. Ibarra, LLL
Enclosure:
As stated cc w/ enclosure See next page 79 2 356 79071gogcjg
063 C f D Q
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- cc w/ enclosure:
V. Stello D. Eisenhut R. Vollmer B. Grimes W. Russell J. Hannon G. Lainas D. Tondi P. Shemanski S. Rhow kb
REQUEST FOR ADDITIONAL INFORMATION PILGRIM UNIT N0. 1 DEGRADED GRID VOLTAGE (TAC 10041)
- 1. Table 3.2.B, Instrumentation That Initiates or Controls the Core and Containment Cooling Systems, Boston Edison Company letter to NRC, dated August 24, 1977, gives a degraded voltage trip point of 3798 volts with 5.2 seconds time delay.
The time delay appears to be too short and cculd cause a problem with shert duration power disturbances. Provide the analysis and basis for your selection of the 5.2 second time delay.
- 2. State and describe total number of channels per bus in your system for the second level undervoltage protection.
State applicable operating modes and action.
Refer to Table 3.3-3, Engineered Safety Feature Actuation System Instrumentation, NRC letter dated June 2,1977 (Safety Evaluation and Statement of Staff Positions Relative to the Emergency Power Systems and Operating.)
- 3. The voltage monitors shall be designed to satisfy the require-
.s of IEEE Std. 279-1971, " Criteria for Protection Systems for Nuciear Power Generating Stations." State your compliance with this requirement, and include sufficient description for us to verify compliance of your design.
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