05000461/LER-2018-003, Load Driver Card Failure Resulting in High Pressure Core Spray Lnoperability

Load Driver Card Failure Resulting in High Pressure Core Spray Lnoperability

ML18233A397
Person / Time
Site:	Clinton
Issue date:	08/17/2018
From:	Kapellas B Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
U-604439 LER 2018-003-00
Download: ML18233A397 (4)

LER-2018-003, Load Driver Card Failure Resulting in High Pressure Core Spray Lnoperability

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(i)
4612018003R00 - NRC Website

text

Clinton Power Station 8401 Power Road Clinton, IL 61727

}c:,-f;x Exelon Generation U-604439 August 17, 2018 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Clinton Power Station, Unit 1 Facility Operating License No. NPF-62 NRG Docket No. 50-461 Subject: Licensee Event Report 2018-003-00 10 CFR 50.73 SRRS5A.108 Enclosed is Licensee Event Report (LER) 2018-003-00: Load Driver Card Failure Resulting in High Pressure Core Spray lnoperability. This report is being submitted in accordance with the requirements of 10 CFR 50.73.

There are no regulatory commitments contained in this report.

Should you have any questions concerning this report, please contact Mr. Dale Shelton, Regulatory Assurance Manager, at (217) 937-2800.

ley T. Kapellas Plant Manager Clinton Power Station KP/lam Attachment: License Event Report 2018-003-00 cc:

Regional Administrator -

Region Ill NRG Senior Resident Inspector Clinton Power Station Office of Nuclear Facility Safety -

Illinois Emergency Management Agency

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2018)

, the NRG may not conduct or sponsor, and a person is not required to respond to, the infonnation coUection.

3.Page Clinton Power Station, Unit 1 05000461 1

OF 3

4. Title Load Driver Card Failure Resulting in High Pressure Core Spray lnoperability

5. Event Date

6. LER Number

7. Report Date

8. Other Facilities Involved I

Sequential I Rev Facility Name Docket Number Month Day Year Year Number No.

Month Day Year 05000 Facility Name Docket Number 06 20 2018 2018 -

003 00 08 17 2018 05000

9. Operating Mode

11. This Report is Submitted Pursuant to the Requirements of 10 CFR §: (Check all that apply)

D 20.2201(bl D 20.2203(a)(3)(il D 50.73(a)(2)(ii)(A)

D 50.73(a)(2)(viii)(A)

D 20.2201(d)

D 20.2203(a)(3)(ii)

D 50. 73(a)(2)(ii)(B)

D 50.73(a)(2)(viii)(B) 1 D 20.2203(a)(1)

D 20.2203(a)(4)

D 50.73(a)(2)(iii)

D 50.73(a)(2)(ix)(A)

D 20.2203(a)(2)(i)

D 50.36(c)(1)(i)(A)

D 50.73(a)(2)(iv)(A)

D 50.73(a)(2)(x)

10. Power Level D 20.2203(a)(2)(iil D 50.36(c)(1)(ii)(A)

D 50.73(a)(2)(v)(A)

D 73.71(aH4>

\\

D 20.2203(a)(2)(m1 D so.36(cH2>

D 50.73(a)(2)(v)(B)

D 73.71 (a)(s>

D 20.2203(a)(2)(iv)

D so.46(a)(3)(ii)

D 50.73(a)(2)(v)(C)

D 73.77(aH11 099 D 20.2203(a)(2)(v)

D 50.73(a)(2)(i)(A)

~ 50.73(a)(2)(v)(D)

D 73.77(aH2Hi>

D 20.2203(a)(2)(vi)

D 50.73(a)(2)(i)(B)

D 50.73(al(2)(vii)

D 73.77(a)(2)(ii)

D 50.73(a)(2)(i)(C)

D Other (Specify in Abstract below or in D.

Safety Consequences

SEQUENTIAL NUMBER 003 REV NO.

00 There were no actual safety consequences associated with the condition described in this report. The HPCS system provides and maintains an adequate coolant inventory inside the reactor vessel to limit fuel cladding temperatures in the event of breaks in the reactor coolant pressure boundary. The system is initiated by either high pressure in the drywell or low water level in the reactor vessel. Though the as-tound HPCS injection valve position rendered the system inoperable, the Reactor Core Isolation Cooling (RCIC) system was operable throughout this event. Although no credit is taken in the safety analysis for the RCIC system, it performs a similar function as HPCS but has reduced makeup capability. HPCS is also backed up by the Automatic Depressurization System in combination with the Low Pressure Coolant Injection [BO] and Low Pressure Core Spray [BM] systems. These systems also remained operable throughout this event.

This event is reportable under the provisions of 10 CFR 50.73(a)(2)(v)(D) as a condition that could have prevented fulfillment of the HPCS system (a single train safety system) to mitigate the consequences of an accident.

E.

Corrective Actions

The original load driver circuit cards were replaced. Additional corrective actions will be discussed in a supplemental report following completion of the failure analysis.

F.

Previous Similar Occurrences There were no previous similar occurrences involving load driver card failure that resulted in HPCS inoperability.

G.

Component Failure Data

Manufacturer: General Electric Hitachi Part Number 147D8455 Load Driver Card Page _3_ of _3_