ML20168A560
| ML20168A560 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 06/16/2020 |
| From: | Christopher Hunter NRC/RES/DRA/PRB |
| To: | |
| Littlejohn J (301) 415-0428 | |
| References | |
| LER 1970-LTR-00 | |
| Download: ML20168A560 (4) | |
Text
PRECURSOR DESCRIPTION AND DATA NSIC Accession Number:
64600 Date:
June 30, 1971
Title:
Loss of Offsite Power at Indian Point.1 The failure sequence was:
- 1. Both sources of offsite power were supplied through a single substation transformer (the normal second transformer was out-of-service for inspection).
- 2. The transformer tripped due to an inadvertent relay actuation, resulting in a total loss of off-site power.
- 3. (S'ince no other failures were reported it is assumed the plant tripped and emergency feedwater was utilized for reactor cooling.)
Corrective action;-
- 1. Modified operating procedures to provide greater assurance that at least two feeders, provided from separate sources, will be available at all times.
Design purpose of failed system or component:
- 1. Provide electric power to plant components when unit generator is not in operation.
Unavailability of system per WASH 1400:*
2 10-5 /hr Unavailability of component per WASH 1400:*
Unavailabilities are in units of per demand D-1.
Failure rates are in units of per hour HR-1.
Loss of offsite Required emergency power jequipment1 Potential Severe Core Damage NSIC 64600 -
Actual Occurrence.f or Loss of Off site Power at Indian Point I (OperationsReport No. 17)
'Operations report does not specify systems utilized after the loss of power occurred beyond this statement.
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CATEGORIZATION OF ACCIDENT SEQUENCE PRECURSORS NSIC ACCESSION NUMBER:
64600 DATE OF LER:
June 30, 1971 (Operations Report No. 17)
DATE OF EVENT: December 26, 1970 SYSTEM INVOLVED:
Of f site ac power COMPONENT INVOLVED:
Transmission lines CAUSE:
Shutdown of Buchanan Substation SEQUENCE OF INTEREST:
Loss of Offsite Power ACTUAL OCCURRENCE:
Shutdown of Buchanan Station.
REACTOR NAMIE:
Indian Point 1 DOCKET NUMBER:
50-3 REACTOR TYPE:
PWR DESIGN ELECTRICAL RATING:
265 MWe REACTOR AGE:
9.0 yr VENDOR:
B&W ARCHITECT-ENGINEERS:
Consolidated Edison Co...
OPERATORS:
Consolidated Edison Co.
LOCATION: 3 iu41es&.SW..of Peekskill, NY DURATION:
N/A PLANT OPERATING CONDITION:
Unknown.
SAFETY FEATURE TYPE OF FAILURE:
(a) inadequate performance; b)failed to start; a
made inoperable; (d)
DISCOVERY METHOD: Operational event.
COMMENT: