05000482/LER-1994-001, :on 931214,local Indicating Lamp Short Circuited Causing Associated Control Power Fuse to Open & Rendering B Centrifugal Charging Pump Room Cooler Inoperable.Similar Lamps Removed

:on 931214,local Indicating Lamp Short Circuited Causing Associated Control Power Fuse to Open & Rendering B Centrifugal Charging Pump Room Cooler Inoperable.Similar Lamps Removed

ML20063E601
Person / Time
Site:	Wolf Creek
Issue date:	02/02/1994
From:	Maynard O, Moles K WOLF CREEK NUCLEAR OPERATING CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-94-001, LER-94-1, WO-94-0010, WO-94-10, NUDOCS 9402100130
Download: ML20063E601 (7)

LER-1994-001, on 931214,local Indicating Lamp Short Circuited Causing Associated Control Power Fuse to Open & Rendering B Centrifugal Charging Pump Room Cooler Inoperable.Similar Lamps Removed

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(iv), System Actuation 10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(viii) 10 CFR 50.73(a)(2)(ii) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(x)
4821994001R00 - NRC Website

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LFCREEK W@f> NUCLEAR OPERATIN

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l Otto L Maynard l

Vice President Plant Operations February 2, 1994 WO 94-0010 l

.U.

S. Nuclear Regulatory Commission ATTN:

Document Control Desk Mail Station PJ--137 Washington, D.

C.

20555

Subject:

Docket No. 50-482:

Licensee Event Report 94-001-00 Gentlemen:

[!

The attached Licensee Event Report (LER) is being submitted pursuant to 10 CFR 50.73 (a) (2) (v) and (vi),

and 10 CFR 21 concerning non-safety related indicating lamps that caused equipment to be inoperable.at the Wolf j

Creek Generating Station.

i Very truly yours,

-:f

$/ /1A^es l

Otto L. Maynard Vice-President Plant Operations.

"i OLM/jad Attachment f

cc:

L.

J.

Callan (NRC), w/a G. A.

Pick (NRC), w/a-l W.

D. Reckley (NRC), w/a l

L. A.

Yandell (N RC ), w/a OSOCSO (f

940210013o 9402O2

{DR ADOCK 05000482

'I I

PDR P.O. Box 411/ Burhngton, KS 66839 / Phone: (316) 364-8831

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' An Equal Opportumty Employer M/F/HCNET

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1 NRC 702M 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB No. 3150-0104 (5-92)

EXPIRES 5/31/95 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS LICENSEE EVENT REPORT (LER)

INFORMATION COLLECTION REQUEST:

50.0 HRS.

FORWARD COMMENTS REGARU!NG BURDEN ESTIMATE TO TPE INFORMATION AND RECORDS MANAGEMENT 6 RANCH (MNBB 77 U.S.

NUC R REGU AT Y COMM SS (See reverse for required number of digits / characters for each block)

REDUCTION PROJECT - (3150-0104),

OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (1)

DOCKET NUMBER (2)

PAGE (3) l Wolf Creek Generatino Station 05000482 1 OF 6 i

TITLE (4)

Non-Safety Related Indicatino Lamps Cause Ecuipment Inocerability EVENT DATE (5)

LER NUMBER (6)

PEPORT DATE (7)

OTHER FACILITIES INVOLVED (8)

MONTH DAY YEAR YEAR SEo'ENTIAL REV.

MONTH DAY YEAR FACILITY NAME DOCKET NUMBER NUMBER NUMBER 12 14 93 94

--01--

00 FACILITY NAME DOCKET NUMBER

't 02 02 94 05000 e

OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR 6: (Check one or more) (11)

]

Mode 1 20.402(b) 20.405(c) 50.73(a)(2)(iv) 73.71(b)

POWER 20.405(a)(1)(i) 50.36(e)(1) x 50.73(a)(2)(v) 73.71(c) 98%

20.405(a)(1)(ii) 50.36(c)(2) 50.73(a)(2)(vil)

X OTHER 20.405(a)(1)(iii) 50.73fe)(2)(1) 50.73(a)(2)(viii) 10 CFR 21 i

20.405(a)(1)(iv) 50.73(a)(2)(ii) 50.73(a)(2)(viii) 20.405(a)(1)(v) 50.73(a)(2)(iii) 50.73(a)(2)(x)

LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHONE NUMBER (include Area Code)

. Mr. Kevin J.

Moles, Manager Regulatory Services (316) 364-8831 l

i COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS PEPORT (13)

CAUSE

SYSTEM COMPONENT MANUFACTURER REPORTABLE

CAUSE

SYSTEM COMPONENT MANUFACTUP.ER REPORTABLE TO NPRDS TO NPROS SUPPLEMENT AL REPORT EXPECTED (14)

EXPECTED MON 1H_

DAY YEAR YES NO (if yes, complete EXPECTED SUBMISSION DATE).

x l

ABSTLACT I

On December 14, 1993, at 0720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br />, a local indicating lamp short circuited causing an associated control power fuse to open, thus rendering the "B"

Centrifugal Charging pump room cooler inoperable.

Similar indicating lamps were installed as local indication for various other safety-related Motor Control Center starters.

This created the potential for a common mode failure that could have led to multiple inoperable safety systems.

Perhaps most significantly, the Boron Injection Tank (BIT) isolation valves could have lost control power, thereby delaying the initiation of high-head cafety injection in an accident situation.

The root cause of the open control power fuse was due to the indicating lamp failing in a manner which led to a lower circuit resistance, and increased current draw.

Additionally, a misapplication of the lamps in seismically qualified equipment is possible as the vendor does not recommend their use under conditions of shock or vibration.

NRC FORM 366 (5-92)

,,U.S. NUCLEA3 C1EGULATORY COMMISSION APPROVED B7 OMB No. 3150-0104 (542)

• EXPIRES 5/31/95 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST:

50.0 HRS.

LICENSEE EVENT REPORT (LER)

FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE TEXT CONTINUATION INFORMATION AND RECORDS MANAGEMENT BRANCH (MNBB 7714),-

U.S.

NUCLEAR REGULATORY COMMIS$10N, WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104),

OFFICE OF MANAGEMENT AND BUDGET, VASHINGTON, DC 20503.

FACILITY NAME (1)

DOCKET NUMBER (2)

LER NUMBER (6L PAGE (3) 05000 YEAR SEQUENTIAL REVISION OF NUMBER NUMBER

' Wolf Creek. Generating Station 482 94

--01--

00 2 of 6

~ TEXT (If more space is required, use additional copies of NRC Form 366A) (17) i

PLANT CONDITIONS

Plant Operational Condition:

Mode 1, 98% thermal power p

Reactor Coolant System Pressure: 2235 psig Reactor Coolant System Temperature:

582.3 Degrees Fahrenheit l

MASIS FOR REPORTABILIII Indicating lamps [IL] that were installed as local indication for various safety-related Motor Control Center (MCC) [MCC] starters created the potential, at Wolf Creek Generating Station (WCGS), for a common mode failure that could have led to multiple inoperable safety systems.

Significantly, the Boron Injection Tank (BIT) isolation valves [BQ-20] could have lost control power, thereby delaying the initiation of high-head safety injection in an accident situation, and the emergency boration valve [CB-20] could have lost power, thereby extending the time necessary to achieve a given concentration of boric acid in the Reactor Coolant System (RCS) [AB].

An Emergency Notification System (ENS) report was made to the NRC Operations Center at 1255 hours0.0145 days <br />0.349 hours <br />0.00208 weeks <br />4.775275e-4 months <br /> on January 4,

1994, under 10 CFR 50.72 (b) (2) (iii)

(D).

This LER is being submitted under the requirements of 10 CFR 50.73 (a) (2) (v) and (vi).

Additionally, the reporting requirements of 10 CFR 21 will be fulfilled by this LER.

DESCRIPTTON OF EVENT On December 14, 1993, at 0720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br />, a local indicating lamp for MCC starter NG02ADR1 short circuited causing the Control Power Transformer (CPT) secondary fuse to open.

This rendered the "B"

Centrifugal Charging Pump room cooler [BQ/CB-CLR] inoperable.

The barned out bulb was blackened. The bulb's lens cover was discolored and had a hole melted through it.

The CPT fuse opened due to excessive current draw when the indicating lamp failure established a circuit of lower resistance.

An inspection of similarly configured control circuits revealed that several other bulbs were burning brighter than normal and generating sufficient heat to discolor the lenses.

The lamp assemblies were a full voltage type (120VAC) and had bulba designated as "120MB",

"SYL 120V",

"S120MB",

and "SR 120MB".

The Class 1E MCC's associated with the Emergency Diesel Generators (EDGs) [DG) use a different type lamp assembly.

These assemblies have a transformer to lower the voltage seen by the bulb.

They use a 7.5VAC bulb marked "S

51".

No abnorTnalities have been observed for these lamp types.

~ -

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.U.S. NUCLEA3 REGULATORV COMMISSICC APPR0t'ED B7 OMB NO. 3150-0104 0' 2)

EXP!RES 5/31/95

'j ESilMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST:

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IHCENSEE EVENT REPORT (LER)

FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE I

TEXT CONTINUATION INFORMATION AND RECORDS MANAGEMENT BRANCH (MNBB 7714),

U.S.

NUCLEAR REGULATORY COMMIS$10N,

" i WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104),

OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

7 FACILITY NAME (1)

DOCKET NUg1R (2)

LER NUMBER (6?

PAGE (3) 05000 YEAR SEQUENTIAL REVISION OF NUMBER NUMBER Wolf Creek Generating Station 482 94

--01--

00 3 of 6 i

TEXT (if more space is required, use additional copies of NRC Form 366A) (17)

I Per engineering recommendation, all MCC local indicating lamps that did not have a voltage reducing transformer were removed on December 17, 1993, to prevent other i

similar occurrences.

Engineering initiated Performance Improvement Request (PIR) 93-1687 to document the concerns with the original qualification and application of these bulbs and lamp assemblies. The Shift Supervisor initiated Reportability - Evaluation Request (RER)93-054 to evaluate reportability under 10 CFR 21, Defects and Noncompliance.

(giditional engineering evaluation revealed that the type of failure experienced, although rare, could have occurred in any or all of the 31 components from which this i

type of bulb was removed.

Attached is a list of the 31 components that potentially could have been affected.

Indicating lamps installed in various -safety-related

{

control circuits created the potential for a common mode f ailure that could have led to multiple inoperable saf et y systems.

The BIT isolation valves could have lost contrcl power, thereby delaying the initiation of high-head safety injection in an accident situation.

The emergency boration valve could also have been affected.

The type of bulb originally supplied with the lamp assemblies could not be conclusively determined.

However, because the spare assemblies in the warehouse were supplied with the same type bulb, it is assumed that 120MB type lamps were originally used.

The average life for these bulbs is 5000 hours0.0579 days <br />1.389 hours <br />0.00827 weeks <br />0.0019 months <br />, or

.57 year.

The vendor i

catalog also states that the 120MB type lamps

..are not recommended for use under l

conditions of shock and vibration."

A seismic event therefore could have aggravated the failure mode described above.

As it was determined that while the bulbs were installed, the potential existed for a common mode failure that could have led to multiple inoperable safety systems; therefore, a 4-hour ENS report was made at 1255 on January 4,

1994, under 10CFR50.72 (b) (2) (iii) (D).

ROOT CATL93 The root cause of the open CPT secondary fuse was due to the indicating lamp failing in a manner which led to a lower circuit resistance, increased current draw, and a substantial amount of heat.

The heat was sufficient to melt a hole in the lens cover, and eventually the bulb drew sufficient current to cause the fuse to open.

Additional root cause determination is pending further of f site analysis and industry coordination.

A misapplication' of the lamps in seismically qualified equipment is I

also possible as the vendor does not recommend their use under conditions of' shock or vibration.

i

M 366A U.S. NUCLEAR REGULATOR 7 COMMISSION APPROUED BY OMB NO.- 3150-0104 EXPIRES 5/31/95 ESilMATED BURDEN PER RESP 0l6E TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST:

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U.S.

NUCLEAR REGULATORY COMMISS10N, WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104),

OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (1)

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LER NUMBER (6:

PAGE (3) 05000 YEAR SEQUENTIAL REVISION Op j

NUMBER NUMBER Wolf Creek Generating Station 482 94

--01--

00 4 of 6 TEXT (if more space is required, use additional copics of NRC Form 366A) (17)

CORRECTIVE ACTIONS

i Carrgative Actions Completedi Performance Improvement Request (PIR) 93-1687 was initiated by engineering to

}

investigate and document the issue.

The Shift Supervisor initiated RER 93-054 to determine reportability.

The LNS report was made to the NRC Operations Center on January 4, 1994.

All indicating lamps that did not have a voltage reducing transformer were removed on I

December 17, 1993, to prevent other similar occurrences.

A summary of the incident was put out on the Nuclear Network on January 7, 1994 as OE 6394.

Inquiries have been received from several utilities, and WCNOC understands that similar failures have been experienced in the industry.

The Operations Department issued a contingency plan to advise operations personnel that a bulb could be installed temporarily for status verification should local operation become necessary.

Future Corrective Actions:

With the removal of the indicating lamps from all affected equipment on December 17, 1993, WCGS was in full compliance.

However, two associated issues are not yet resolved.

WCGS has been in communication with the present Class 1E supplier of the MCCs, but has I

yet to determine if the lamps were included in the original equipment qualification due'to a lack of detailed documentation.

The concen

'th the original qualification and application of the bulbs and lamp assemblies are 1

\\tly being pursued under PIR 93-16B7.

A completion date cannot be assigned as the actions to be taken by WCGS are dependent upon independent laboratory analysis and industry discussions.

The use of a different type bulb or the transformer type lamp assemblies in the affected equipment is still being considered under Corrective Work Request (CWR) 06859-93.

The due date for CWR 06859-93 is April 29, 1994.

l

'l NRC FOCM 366A U.S.NUCLEARkEGULATORYCOMMIS$10N

^

"

• ll~ (

EXPIRES 5/31/95 APPROVED BY OMB NO. 3150-0104 ESilMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST:

50.D HPS.

LICENSEE EVENT REPORT (LER)

FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE TEXT CONTINUATION INFORMATION AND RECORDS MANAGEMENT BRANCH (MNBB 7714),

U.S.

NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104),

OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (1)

DOCKET NUMBER f2)

LER NUMBER (61 PAGE (3)

- l 05000 YEAR SEQUENTIAL REVISION OF

.j NUMBER NUMBER i

Wolf Creek Generating Station 482 94

--01--

00 5 of 6 I

TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

SAFETY ANALYSIS

The Class lE McC's provide a means to control power to various associated safety-related plant equipment.

Overcurrent protection is provided via molded case circuit ~

breakers and CPT fuses.

Local indicating lights for control power are present on some MCC applications in which local control is provided and indicate the controlled equipment's status (i.e.,

running, stopped, fast speed, slow speed, etc.)

The

. equipment stetus is either redundantly displayed in the Control Room or is alarmed on abnormal conditions.

Per the Updated Safety Analysis Report (USAR), Section 7.5, the status indication provided by these lights is not required for safety and performs no active safety-related function.

The 120MB type bulbs may not be appropriate to the application. in which they were used.

Several lamps failed in such a manner as to draw increased current.

However, a failure such as the one experienced on December 14, 1993, where the excess amperage was sufficient to blow the CPT secondary fuse, is considered to be rare.

No other failures of this type have been experienced at WCGS, More importantly, there has-never been an incident requiring the accident ndtigating capabilities of the affected equipment.

Therefore, there were no adverse consequences to plant safety and public health and safety were assured at all times.

OTHER SIMILAR OCCURRENCES There have been no previous similar occurrences reported at the Wolf Creek Generating Station.

i

U.S. NUCLEAR REGULATC3Y COMMISSION APPROVED BY OMB No. 3150-0104 lNR,C FORM 366A (5-92)

EXPIRES 5/31/95 I

ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST:

50.0 HRS.

LICENSEE EVENT Ri: PORT (LER)

FORWARD COMMENTS RECARDING BURDEN ESTIMATE TO THE INFORMATION AND RECORDS MANAGEMENT BRANCH (MNBB TEXT CONTIIE.TTION 7714),

U.S.

NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104),

OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (1)

DOCKET NUMBER (2)

LER NUMBER (61 PAGE (3) l 05000 YEAR SEQUENTIAL REVISION OF NUMBER WUMBER Wolf Creek Generating Station 482 94

--01--

00 6 of 6 TEXT (if more space is required, use additional copies of NRC Form 366A) (17) i ATTACHMENT TO LER 94-001-00 i

MCC Cubicle Component Equipment Description NG01A AF3 DCGK04A CONTROL ROOM PRESSURIZATION FAN NG01A BF3 DSGLO9A SAFETY INJECTION PUMP ROOM COOLER NG01A CF3 DSGL10A RESIDUAL HEAT REMOVAL PUMP ROOM COOLER NG01A EF1 BNLCV112D RWST TO CHARGING PUMP VALVE NG01A GR1 DSGL12A CENTRIFUGAL CHARGING PUMP ROOM COOLER l

NG01A GR2 DSGL13A CONTAINMENT SPRAY PUMP ROOM COOLER NG01B BF4 DCGNO3A HYDROGEN MIXING FAN NG01B CF3 DCGNO3C HYDROGEN MIXING FAN i

NG01B DR4 EMHV8803A BORON INJECTION TANK INLET ISOLATION VALVE NG01B EF1 DSGL15A PENETRATION ROOM COOLER i

NG018 ER2

e V8801A BORON INJECTION TANK DISCHARGE ISOLATION VALVE NG01T AF1 D5GN01 A CONTAINMENT COOLER FAN NG02A BR3 DSGL13B CONTAINMENT SPRAY PUMP ROOM COOLER NG02A CF3 DSGLO98 SAFETY INJECTION PUMP ROOM COOLER NG02A DF3 DSGL10B RHR PUMP ROOM COOLER NG02A DR1 DSGL12B CENTRIFUGAL CHARGING PUMP ROOM COOLER NG02A GF1 DCGK04B CONTROL ROOM PRESSURIZATION FAN NG02A HR3 BNLCV112E RWST TO CHARGING PUMP VALVE NG02B AF2 DSGL15B PENETRATION ROOM COOLER NG02B BF4 DCGNO3B HYDROGEN MIXING FAN NG02B CF3 DCGNO3D HYDROGEN MIXING FAN NG02T AFI DSGN01 B CONTAINMENT COOLER FAN NG03C CF1 DCGK03A CONTROL ROOM FILTRATION FAN NG03C KF1 DSGG04A SPENT FUEL POOL PUMP ROOM COOLERS NG03T AF1 DSGNO1C CONTAINMENT COOLER FAN NG04C BF2 DCGK03B CONTROL ROOM FILTRATION FAN NG04C EF1 DSGG048 SPENT FUEL POOL PUMP ROOM COOLER NG04C KF2 EMHV8803B BORON INJECTION TANK INLET ISOLATION VALVE NG04C KF3 EMHV8801 B BORON INJECTION TANK DISCHARGE ISOLATION VALVE NG04C PF2 BGHV8104 BORIC ACID FILTER TO CHARGING PUMP NG04T AFI DSGN01 D CONTAINMENT COOLER FAN i