ML19308D557

RO-77-75:on 770702,absolute Position Indication for All Regulating Rods Lost While Performing Operability Test on Rod 3 Group 6.Caused by Crowbarred 15 Volt Power Supply Due to Spike of Unknown Origin.Sys Restored

ML19308D557
Person / Time
Site:	Crystal River
Issue date:	07/28/1977
From:	Stewart W FLORIDA POWER CORP.
To:
Shared Package
ML19308D554	List: ML19308D553 ML19308D557
References
NUDOCS 8002280987
Download: ML19308D557 (2)

Text

_ __ _ _ _ -

i Lil,tlWtt CV CPJ i MCPUMI ik* * ,

CONTROL BLOC. l l l l l l (PLEASE PRINT ALL RtCUtRED INFCRM AT*C.

6

{ ~

1 i

[ AME UCENSE NUMBER

, PE

, (J

,7 l FlL 89 l ClR lP l314l l0 l0 l-l0 l 0 l 0 l 0 l 0 l-l 0 l 0 l l 4 l1 l1 l1 l 1l l0 l3 l 25 32 15 26 30 31 CATEcoRY " 7PE T E CoCKET NUMBER

• EVENT oATE REPORT CATE l 0 1 CON'T l 7 8 l_l l Ll lo l5 l0 l-l0 l3 l0 l? l l0 l7 l0 l2 l7 l7l l 0 l 7 l2 l8 l7 l~,

57 $8 59 60 61 68 69 74 75 t EVENT DESCRIPTION I gg l In mode 2 operation while performing operability test of rod 3 group 6 API, the absolute j 7 89 .

t !

, Ql 7 89 position indication for all regulating rods was lost, creating a ec.2dition as defined L

l Ql by Tech Spec 3.0.3. Redundancy was maintained with the relative position indication.

7 89 L l

, Ql 7 09 This was a non-repetitive occurrence. Maintenance restored the API system operable

, E DE l within 8 minutes. (LER 77-75) 7 89 m,, E, EE CCCE COMpor4ENT CCCE ACT 4 VCLATCN Q lIl Dl lF l 7 89 10 l Il Nl S l Tl Rl Ul lNl l Dl1 l 5 l 0 l g ,

11 12 17 43 44 47 48 .

CAUSE DESCRIPTION 'p  ;~

e l The 15 volt power supplies for the API system crowbarred due to a spike of unknown 7 89 6-0 l origin and were reset restoring system operability; 6

f ,

9

• E l

's'TE  % POWER oTHER STATUS -Cr5 CVERY e6 COWRY CESCMT:CN l

Q 70

]

9 10

[0 l0 l0 l l 12 13 NA l 44 l Al 45 l

'46 1A 8.

ACTMTV CCATENT -

RELEASEO AMCUNT OF ACTMTV LOCAT:CN CF RELEASE 1

] CFyRELEASE l NA l l NA 7 8 .9 10 11 44 45 , St PERSONNEL EXPOSURES NUMBER TYPE DESC341PTICN Q l0 l0 l0 l 7 89 11 Wl12 13 NA Es PERSONNEL INJUAIES -

NUMBER DESCRPTON E l0l0l0_l l NA 7 89 11 .12 ,

SC OFFSITE CONSECUENCES

,Ql -

NA - -

l 7 89 Bt LOSS OR OAMAGE TO FAC:UTY TYPE CESCRPTON .

1 7 89 bl 10 NA LC PUBUCITY l 17 l NA I

7 89 UC

, ADDITIONAL FACTORS as89

}l See attached Supplementary Information 8 0 02 280 fp 7 89 , to NAME:

W. P. Stewart PHONE: (813) 866-4159

, _q,- l .

cPo one.ssT l _ _ _ _ .

. ~

~ ~ '

SUPPLDfENTARY INFORMATION

~,,..

N. Report No.: 302/77-75 .

4

2. Facility: Crystal River Unit #3 *

3. Report Date: 28 July 1977

4. Occurrence Date: 2 July 1977

5. Identification of Occurrence:

The loss of all absolute position indication resulted in a limiting condition for operation in excess of those addressed in the Specifications as defined by Technical Specification 3.0.3.

6. Conditions Prior to Occurrence:

Mode 2 startup operation.

7. Description of Occurrence: .

At 0435 while performing operability test of the absolute position indication of rod 3 of .:.

group 6, the absolute position indication for all rods was lost. The Electrical Supervisor i was immediately notified and preparations were made to go to hot standby within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, as required by Technical Specifications. The v.ssolute position indication system was restored operable within 8 minutes.

Designation of Apparent Cause:

An apparent , spike from an unknown origin causet a crowbar of the API 15 alt power supplies. The power supplies were reset and th 1 API system restored operable.

9. Analysis of Occurrence:

3 There were no safety implications as a result of this occurrence.

10. Corrective Action:

No corrective action deemed necessary as normal maintenance restored system operability.

11. Failure Data:

i This was not a repetitive occurrence.

- - .-- .. .. - -