ML19319B809

From kanterella
Jump to navigation Jump to search
RO NP-33-77-64:on 770827,reactor Coolant Pump Motor 1-1-2 Tripped W/Instantaneous Ground & Differential Current Relay Indicating Fault.Caused by Damaged B&C Phase Surge Capacitors.Capacitors Repaired & Setpoints Reset
ML19319B809
Person / Time
Site: Davis Besse Cleveland Electric icon.png
Issue date: 09/22/1977
From: Beeler T, Lingenfelter J
TOLEDO EDISON CO.
To:
Shared Package
ML19319B724 List:
References
NUDOCS 8001270273
Download: ML19319B809 (2)


Text

l l

. = -.

  • l

',$ t.lCENSEE EVENT REPORT s

CONtnot et oCat l,, { l l l l]

' e.m <ece~,. ~... . 'w.re en.;

@ ]OIHIDlBlSllj l j 0] -J 010 i Ni P lF l -10 ,, l 3lm l 4 l lj,1]l [ l

.....o.. :: r t.1,= : ..~u... .N~.,... . ....o...

con'1 [ 0 15 i O f .-r 0 13 14 16 q

1812#71717I 1019l 2121717g (vt Nt ut SCRit t'oM gi Reactor Coolant Pump 1-1-2 tripped removing one of the two Reactor j 7 89 gl,-Coolant

, , Pumps of the loop from operation. Station in Action Statement in3 81

es of Technical Soecification 3.4.1. CIP-33-77-641 I is]

,EE, L, i SO 8L i Og cont C OwmM8 a88 Coor svwet ( . we vYact nr. veos a s ecas 8 ClB 7 89 to 1 LfJ 11

[M12 i 0 I T I O I R1XJ 17 UN 4J

. (W f1 (2 I O 1 [NJ 44 47 e4 CAUST Cf 5Ca:PteoN gl The B&C phase surge capacitors were discovered to be damaged. The l

gI exact cause of the damage is not known. sa j

% y ag clo

\ 8I89 7 I (53 8 =UU s._,. ... ..... .

NA

.u=x I LAj NA o._........o,

? O 9 1010!012 l (1 to 44 4%

[_

e6

_j 80 sei o o[Ns t auoume or .Ctewe f v 8

7 8 l3J . lZj l NA 9 to 1* *4 I l NA Loc tio% er .ttg.gc l

45 *Q Pf n50NNE L E EPC$URe$

=voce . ' v o et op.sc.eeteon 8 189O! 0 t o i tzj i NA

) 18 12 13 j

Pt nsoNNit 'NJUH8E5

=vuota na sc .ea r som

%.WJ4,5 ' "A a '

80 Of 8 Site CoNSE oUf NCES NA l

LOSS CR onwabt,10 7 ACI(tT V in]

' < .t otsc.ietsom a g ar PUBLICITV 31

> es NA l 14 0 accattoNat 8 aCloRS 3

s e i, NA l a0

\ 31a.

y >

, , , Jacque Lingenfelter/T. Beeler (4197'259-5000, Ext. 251

,o 1

rwoNr

~

Dva 123-1 8001270 2 7 3

O t TOLEDO EDISON CCMPANY DAVIS-3. ESSE UNIT ONE NUCLEAR POWER STATION SUPPLEMENTAL INFORMATION FOR LER NP-33-77-64 i

DATE OF EVENT: August 27, 1977 j FACILITY: Davis-Besse Unit 1 IDENTIFICATION OF OCCURRENCE: Reactor Coolant Pump Motor 1-1-2 was declared inoperable on August 27, 1977.

Conditions Prior to Occurrence: The plant was in Mode 2, with Power (%7) = 125 and Load (SI) = 0.

Description of Occurrence: Reactor Coolant Pu=p Motor 1-1-2 tripped at 17/.0 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> on August 27, 1977, with instantaneous ground (50GS) and differential current relay (87m/A-B-C) targets indicating the fault. This placed the Station into the Action Statement of Technical Specification 3.4.1 since one of the two Reactor Coolant Pumps in the loop were not in operation.

D Designation of Apparent Cause of Occurrence: Upon inspection of the Reactor Coolant Pump 1-1-2 =otor terminal box, Station maintenance personnel discovered B&C phase surge capacitors to be damaged. The exact cause of tha damage of the surge capacitors is not known.

Analysis of Occurrence: There was no danger to the health and safety of the 7

public or Station personnel. The ther=al pcwer was at a low value and the remaining three Reactor Coolant Pumps were supplying the required coolant flow.

i .;y Corrective Action: The high flux and the flux-delta-flux setpoints were reset for three pump operation as required by the Action Statement of Technical Specification 3.4.1. Station maintenance personnel replaced C-phase surge capacitors and re-installed B-phase surge capacitors after caulking the crack in the porcelain and opening in the seam with RTV silicone sealant.

~ ~

At 0058 hours6.712963e-4 days <br />0.0161 hours <br />9.589947e-5 weeks <br />2.2069e-5 months <br /> on August'317 1977, Reactor Coolant Pump 1-1-2 was declared operable.

This removed the station from Action Statement of Technical Specification 3.4.1.a.

On August 29, 1977, an inspection was made on the remaining reactor coolant pump motors. A defective capacitor was found in A phase for Reactor Coolant Pump 1-2-2.

Station maintenance personnel replaced A phase surge capacitor with a new one. A f Facility Change Request (77-280) has been prepared to investigate the position of the surge capacitors in the reactor coolant pu=p motor terminal boxes.

4

(

i Failure Data: No previous similar events have occurred.

I i

_.