05000280/LER-1988-023, :on 880802,C Steam Generator Channel IV Steam Flow Failed to Low Flow Indication.Caused by Failed Multiplier/Divider Unit Power Supply Transformer.Technicians Called in & Placed Channels in Trip Mode

:on 880802,C Steam Generator Channel IV Steam Flow Failed to Low Flow Indication.Caused by Failed Multiplier/Divider Unit Power Supply Transformer.Technicians Called in & Placed Channels in Trip Mode

ML18152B113
Person / Time
Site:	Surry
Issue date:	08/30/1988
From:	Benson D VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
88-043, 88-43, LER-88-023, LER-88-23, NUDOCS 8809060236
Download: ML18152B113 (4)

LER-1988-023, on 880802,C Steam Generator Channel IV Steam Flow Failed to Low Flow Indication.Caused by Failed Multiplier/Divider Unit Power Supply Transformer.Technicians Called in & Placed Channels in Trip Mode

Event date:
Report date:
2801988023R00 - NRC Website

text

NRC fbrin 3111 (9-83)

FACILITY NAME (11 TITLE (41 LICENSEE EVENT REPORT (LER) s, ll'"l"V PnWAI" c:a:=itinn 11 nit,

POW 28-06-01 U.S. NUCLEAR REGULATORY COMMISSION APPROVED 0MB NO. 3160--0104 EXPIRES: 8/31/88 DOCKET NUMBER (21 I

PAGE 131 O I 5 I O I O I O b I a In 1 I OF 1n I '2 IIC,11 S,r. StA;am Flnw Ch;:innAI IV F;ail... rl I nw r '"'" Tn l=:=iil... rl IIA,,ltinli..... Jr"lh,ir!.....

EVENT DATE (51 LER NUMBER (61 REPORT DATE (71 OTHER FACILITIES INVOLVED (8)

MONTH DAY YEAR YEAR.{% s.e~~~~~~AL tt: ~~iii::~~ MONTH DAY YEAR FACILITY NAMES DOCKET NUMBER(SJ n I ~ rl 2 s s s Is - n I 2 13 - o Io o I s 3 lo s Is OPERATING MODE (Ill THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Ch<<k OM or mor* of th* follo,ying) (111 20.402(b) 20.40ll(cl li0.73(1J(Zl(iv) 20.40ll(1)(1 )(I) li0.31(cl(1 J li0.73(1)(2J(v) 73.71(b) 73.71(c)

POWER I LEVEL 1101 1 IO I 0 li0.73(1)(21(vll)

OTHER (S,,.cify in Abrtnct 20.40ll(1)(1 )(HJ li0.31(cl(2) b*low *nd In T*Kt, NRC Form 20.40ll(1)(1 )(Ill)

X II0.73(11(2)(1) li0.73(1H2llvllll(Al 366A) 20.40ll(1l11 l(lvl li0.73(11(21(11) li0.73(11(2l(vllll(Bl 20.40lll*H1 l M li0.73(11(2)(1111 li0.73(1l12llxl LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHONE NUMBER AREA CODE D. L. Benson, Station Manager 8 f O I 4 3' I 5 I 71-I 3 11 18 14 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 113)

CAUSE SYSTEM COMPONENT MANUFAC-TURER R~60

~;:gkE i!i!i!i!i!i!i!i!i!i!i!i!i!i!i!i!i!l!l!ili!i!i!i!i!i!i CAUSE SYSTEM COMPONENT MANUFAC-TURER X J I E XI XI X IX W1 1 12 I 0 y

I I

I I

I I

I I

. I I I I I I I

I I I I

I I

l!i!l!lliiiliiilililiiililiiiiiiil//ii/ljjjjjjjjjjj SUPPLEMENTAL REPORT EXPECTED (141 MONTH DAY Y

i, YES (If yn, compl*r. EXPECTED SUBMISSION DATE)

EXPECTED SUBMISSION DATE (16)

I I

I ABSTRACT (Limit to 1400,plt:ft, I.*.. *ppro,rim1r.ly flftHn 1in11l*rpoc* ry,,.wrimn /inn) 1111 NRC Form 381 19-83)

At 1928 hours0.0223 days <br />0.536 hours <br />0.00319 weeks <br />7.33604e-4 months <br /> on August 2, 1988, with Unit 1 operating at 100% power, "C" Steam Generator (S/G) Channel IV Steam Flow (FI 1495) failed to a low flow indication.

This channel of steam flow provides an input into the reactor trip matrix, and safety injection and main steam isolation matrix.

With this channel failed, and not in the trip mode, the degree of redun4~ncy requirements of Technical Specification (T. S.)

tableS~r.1-2, was not met *

.,';t,.'.,*:'t):::.

At 2TJi'~: hours, the failed steam flow channel inputs into the reactor trip and safety injection logics were placed in the trip mode satisfying T. s. requirements.

A failed multiplier/divider unit was replaced in the "C" S/G Channel IV Steam Flow circuitry and the channel was tested and returned to service at 2252 hours0.0261 days <br />0.626 hours <br />0.00372 weeks <br />8.56886e-4 months <br />.

The "C" S/G Channel failed** to a low indication due to* a failed multiplier/divider unit's power supply transformer.

Instrumentation technicians were called in, and placed the affected channel.s in the trip mode.

The multiplier/divider was replaced and the steam flow channel was tested and returned to service.

8809060236 880830 PDR ADOCK 05000280 S

PDC

~

-~-- ~-----

r,-~* --------------~ (9-831 LICENSEE EVENT REPORT (LER) TEXT CONTINUATION FACILITY NAME (11 DOCKET NUMBER 121 POW 28-06-01 U.S. NUCLEAR REGULATORY COMMISSION APPROVED 0MB NO. 3150-0104 EXPIRES: 8/31 /88 LEA NUMBER 161 PAGE 131 Surry Power Station, Unit 1 o Is I o I o I o I 218 f o 8 18

- o 12 I 3 -

o I o o I 2 oF o I 3 TEXT /ff more space i8 required, use additional NRC Form 366A's/ 1171 NRC FORM 3HA 19-831 1.0 Description of the Event At 1928 hours0.0223 days <br />0.536 hours <br />0.00319 weeks <br />7.33604e-4 months <br /> on August 2, 1988, with Unit 1 operating at 100% power, "C" Stearn Generator (S/G)

Channel IV Stearn Flow (FI 1495) {EIIS-JE} failed to a low flow indication.

This channel of steam flow provides an input into the low S/G level in coincidence with feed flow/steam flow mismatch reactor trip matrix, and the high steam flow in coincidence with low tavg or low steam line pressure safety injection and main steam isolation matrix.

With this channel failed, and not in the trip mode, the degree of redundancy requirements of Technical Specification (T. S.) table 3.7-2, was not met and T. s. 3.0.1 was in effect.

At 2116 hours0.0245 days <br />0.588 hours <br />0.0035 weeks <br />8.05138e-4 months <br />, the failed steam flow channel inputs into the reactor trip and safety injection logics were placed in the trip mode satisfying T. s.

requirements.

A failed multiplier/divider unit was replaced in the "C" S/G Channel IV Stearn Flow circuitry and the channel was tested and returned to service at 2252 hours0.0261 days <br />0.626 hours <br />0.00372 weeks <br />8.56886e-4 months <br />.

2.0 Safety Conseguences and Implications The "C" S/G Channel IV steam flow provides an input into the low S/G level in coincidence with feed flow/steam flow mismatch reactor trip matrix, and the high steam flow with low tavg or low steam line pressure safety injection and main steam isolation matrix.

The reactor trip is for protection against a loss of heat sink and the safety injection with main s(e*am isolation is for protection against a main steam 1tJi~.'. break.

During the time the failed steam flow channel was not in the trip mode, the minimum number of steam flow channels required by T. s., that provides an input to the above protection logics, was maintained.

In addition, all other parameters that input to the protection logics remained operable.

Consequently, a reactor trip and/or safety injection with main steam isolation would have occurred, if required.

Therefore, the health and safety of the public were not affected.

• u.s. GPO: 1988-520-589100070

\\

NRC Form 388A 19-831 FACILITY NAME (11 LICENSEE ENT REPORT (LERI TEXT CONTINUATION DOCKET NUMBER 121 POW 28-06-01 U.S. NUCLEAR REGULATORY COMMISSION APPROVED 0MB NO. 3150-0104 EXPIRES: 8/31 /88 LER NUMBER (61 PAGE (31 Surry Power Station, Unit 1 0

5 0

0 0

TEXT /If mor. space is fW/UirtK/, UlltJ additioMI NRC Form Jl5ll'A'a) (171 Nl'IC FOl'IM 3HA (9-831 3.0

cause

The "C" S/G Channel IV steam flow failed to a low indication due to a failed multiplier/divider unit's power supply transformer.

This resulted in an erratic signal output.

4.0 Immediate Corrective Action(s)

Instrumentation technicians were called in, and placed the affected channels in the trip mode.

5.0 Additional Corrective Action(s)

The multiplier/divider was replaced and the steam flow channel was tested and returned to service.

6.0 Action(s) Taken to Prevent Recurrence Although the reactor protection and safety injection instrumentation is periodically tested and calibrated, random failures of this nature cannot be prevented.

7.0 Similar Events

None.

8.0 Manufacturer/Model Number Hagan/127-112.

• u.s. GPO, 1988-520-589100070

}----

)

• ~. -...

August 30, 1988 U.S. Nuclear Regulatory Commission Document Control Desk 016 Phillips Building Washington, D.C.

20555 Gentlemen:

VIRGINIA ELECTRIC ANO POWER COMPANY Surrv P~r Station P. 0. Box 315 Surrv, Virginia 23883

. Serial No. :

Docket No.:

Licensee No. :

88-043 50-280 DPR-32 Pursuant to Surry Power Station Technical Specifications, Virginia Electric and Power Coapany hereby suba.its the following Licensee Event Report for Surry Unit 1.

REPORT NUMBER SS-023-00 This report has been reviewed by the Station Nuclear Safety and Operating Committee and will be reviewed by Safety Evaluation and Control.

Very truly yours, David L. Benson Station Manager Enclosure cc:

Dr. J. Nelson Grace Regional _Adwinistrator Suite i900 101 lfar1.etta Street, NW Atlaniai°~- Georgia 30323