ML20168A460
| ML20168A460 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 06/16/2020 |
| From: | Christopher Hunter NRC/RES/DRA/PRB |
| To: | |
| Littlejohn J (301) 415-0428 | |
| References | |
| LER 1979-034-00 | |
| Download: ML20168A460 (4) | |
Text
PRECURSOR DESCRIPTION AND DATA NSIC Accession Number:
150051 Date:
May 30, 1979
Title:
Failure of Two Diesel Generators at Dresden 2 The failure sequence was:
- 1. The unit 2 diesel generator had failed for reasons unspecified.
- 2. An operability test of unit 2/3 was immediately performed, however, it failed to start.
- 3. The reactor was placed in cold shutdown.
Corrective action:
- 1. The starting logic was modified.
Design purpose of failed system or component:
Emergency Power provides a.c. power when of fsite power is unavailable.
Unavailability of system per WASH 1400: Emergency Power:
I x 10-3 /Di Unavailability of component per WASH 1400:
- Diesel Generator Failure to Start:
3 x 10-3 /1)
Umavailabilities are in units of per demand D-1.
Failure rates are in units of per hour HR71.
IDiesel Generator #2 An Operability Test Of The Reactor Was Placed Had Failed Unit 2/3 Also Failed In Cold Shutdown Potential Severe Core Damage No No, no LOOP No NSIC 150051 -
Actual Occurrence of Failure of Two Diesels at Dresden 2
Loss of Reactor Diesel Reactor Made Sub-RCIC/1HPCI ADS/LPCI Ln Potential Sequence Offsite Scram Start and critical by the Initiates CS TemSevere No.
Power Load SBLCS Or Rods Are Initiates Core Cr Manually Driven In jCoig Damage
~~
No1 Yes 2
No 3
Yes 4
Yes 5
H()No 6
EYes 7
Yes 8
No 9
Yes 10 No 11 Yes 12 Yes 13 C )Yes 14 Yes 15 NSIC 150051 -
Sequence of Interest for Failure of Two Diesel Generators at Dresden 2
CATEGORIZATION OF ACCIDENT SEQUENCE PRECURSORS NSIC ACCESSION NUMBER: 150051 DATE OF LER:
June 12, 1979 DATE OF EVENT:
May 30, 1979 SYSTEM INVOLVED:
Emergency Power COMPONENT INVOLVED: Diesel Generators CAUSE:
Failure of the air starter motor SEQUENCE OF INTEREST:
Loss of offsite power ACTUAL OCCURRENCE:
Failure of two diesels REACTOR NAM~E:
Dresden 2 DOCKET NUMBER:
50-237 REACTOR TYPE:
BWR DESIGN ELECTRICAL RATING:
794 MWe REACTOR AGE:
9.4 yr VENDOR:
General Electric ARCHITECT-ENGINEERS:
Sargent and Lundy OPERATORS:,
Commonwealth Edison LOCATION:
Nine miles East of Morris, Ill.
DURATION:
360(a) hours SAFETY FEATURE TYPE OF FAILURE:
(a) inadequate perfozinace; (b) failed to start; (3 made inoperable; (d) ___________
DlISCOVERY METHOD:
Test COMMENT: