ML13107A625
| ML13107A625 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 04/16/2013 |
| From: | Bhalchandra Vaidya Plant Licensing Branch 1 |
| To: | Darling T, Dosa J, Vandeputte D Constellation Energy Group, Niagara Mohawk Power Corp |
| References | |
| TAC MF1022 | |
| Download: ML13107A625 (1) | |
Text
Vaidlya, Bhalchandra From:
Vaidya, Bhalchandra Sent:
Tuesday, April 16, 2013 1:32 PM To:
'Dosa, John J'; 'Darling, Theresa H'; 'Vandeputte, Dennis E' Cc:
Matharu, Gurcharan; Mathew, Roy; Meighan, Sean; Martinez-Navedo, Tania
Subject:
Draft supplemental Information Requirement, MF1022, Nine Mile Point Unit 1, LAR Re: DG Initiation-Degraded Voltage...
John, Theresa, and Dennis, The Draft Supplemental Information Requirements for completion of Acceptance Review of the License Amendment Request submitted by letter dated March 8, 2013, is provided below:
Nine Mile Point Nuclear Station, Unit 1 Docket No. 50-220 License Amendment Request - Diesel Generator Initiation - Degraded Voltage Time Delay Setting Change TAC # MF1022 Supplemental Information Requested by NRC Staff The proposed amendment would modify Technical Specification (TS) Table 3.6.2i, "Diesel Generator Initiation," by revising the existing 4.16kV Power Board (PB) 102/103 Emergency Bus Undervoltage (Degraded Voltage) Operating Time value and updating the Set Point heading title. However, this TS has a related degraded voltage relay (DVR) dropout setpoint and current value of
-3705 volts remains unchanged.
The ongoing Component Design Basis Inspections have identified inadequate voltage setpoints at several nuclear plants and the NRC recently issued Regulatory Issue Summary (RIS) 2011-12 "Adequacy of Electric Distribution System Voltages" to inform the industry about the findings at some plants. In order for the staff to complete the review of the proposed amendment request, please provide additional information on the voltage setpoint as requested below.
- 1. Validate that the voltage setpoint of 3705V satisfies the criterion delineated in the RIS as related to the starting and running voltage requirements for the safety related loads at all busses.
- 2.
Provide excerpts from calculation(s) that establish the limiting voltage at various safety buses for equipment operability with the 102/103 Power Boards at 3705V.
Please contact me immediately to schedule a tele-conference to ensure that the licensee clearly understands these supplemental information requirements.
Bhalchandra K. Vaidya Licensing Project Manager NRC/NRRIDORLILPL1 -1 (301)-415-3308 (0) bhalchandra.vaidyaOnrc.qov 1