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| {{Adams
| | #REDIRECT [[05000250/LER-2016-001]] |
| | number = ML16109A155
| |
| | issue date = 04/07/2016
| |
| | title = LER 16-001-00 for Turkey Point, Unit 3 Regarding Loose Breaker Control Power Fuse Caused the 3B Emergency Containment Cooler to Be Inoperable Longer than Allowed
| |
| | author name = Summers T
| |
| | author affiliation = Florida Power & Light Co
| |
| | addressee name =
| |
| | addressee affiliation = NRC/Document Control Desk, NRC/NRR
| |
| | docket = 05000250
| |
| | license number = DPR-031
| |
| | contact person =
| |
| | case reference number = L-2016-071
| |
| | document report number = LER 16-001-00
| |
| | document type = Letter, Licensee Event Report (LER)
| |
| | page count = 4
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| }}
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| | |
| =Text=
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| {{#Wiki_filter:* FPL .. U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555-0001 Re: Turkey Point Unit 3 Docket No. 50-250 Reportable Event: 2016-001-00 Date of Event: February 8, 2016 L-2016-071 10 CFR § 50.73 APR 0 7 2016 Loose Breaker Control Power Fuse Caused the 3B Emergency Containment Cooler to be Inoperable Longer Than Allowed by Technical Specifications The attached Licensee Event Report 05000250/2016-001-00 is submitted pursuant to 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by the Technical Specifications.
| |
| If there are any questions, please call Mr. Mitch Guth at 305-246-6698.
| |
| Sincerely,
| |
| /fhomas 1;ummers Vice President Turkey Point Nuclear Plant Attachment cc: Regional Administrator, USNRC, Region II Senior Resident Inspector, USNRC, Turkey Point Nuclear Plant Florida Power & Light Company 9760 SW 344th St., Homestead, FL 33035 NRC FORM366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 (11-2015) l:stimated burden per response to comply with this mandatory collection request 80 hours. '.'1fa** Reported lessons learned are incorporated*
| |
| into the licensing process and fed back to indusiry.
| |
| t Send comments regarding burden estimate to the FOIA, Privacy and Information Collections LICENSEE EVENT REPORT (LER) Branch. (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by ** .. , ...... : .. :* internet e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and (See Page 2 for required number of Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, digits/characters for each block) DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRG may not conduct or sponsor, and a person is not required to respond to, the information collection.
| |
| : 1. FACILITY NAME 2. DOCKET NUMBER 3. PAGE Turkey Point Unit 3 05000 250 1 OF 3 4. TITLE Loose Breaker Control Power Fuse Caused 3B Emergency Containment Cooler to be Inoperable Longer Than Allowed 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 MONTH DAY YEAR NUMBER NO. 05000 FACILITY NAME DOCKET NUMBER 2 8 2016 2016 -001 -00 4 7 2016 05000 9. OPERATING MODE 11. THIS REPORT IS SUBMITTED-PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) D 20.2201(b)
| |
| D 20.2203(a)(3)(i)
| |
| * D 50.73(a)(2)(ii)(A)
| |
| D 50.73(a)(2)(yiii)(A) 1 D 20.2201(d)
| |
| D 2*0.2203(a)(3)(ii)
| |
| D 50.73(a)(2)(ii)(B)
| |
| D 50.73(a)(2)(viii)(B)
| |
| D 20.2203(a)(1)
| |
| D 20.2203(a)(4)
| |
| D so.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)(ii)
| |
| D 50.36(c)(1)(ii)(A)
| |
| D 50.73(a)(2)(v)(A)
| |
| D 73.71(a)(4)
| |
| D 20.2203(a)(2)(iii)
| |
| _ D so.36(c)(2)
| |
| 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(a)(1) 100 D 20.2203(a)(2)<v>
| |
| D 50.73(a)(2)(i)(A)
| |
| D 50.73(a)(2)(v)(D)
| |
| D 73.77(a)(2)(i)
| |
| D 20.2203(a)(2)(vi)
| |
| [{] 50.73(a)(2)(i)(B)
| |
| D 50.73(a)(2)(vii)
| |
| D 73.77(a)(2)(ii)
| |
| D 50.73(a)(2)(i)(C)
| |
| D OTHER Specify in Abstract below or in NRC Form 366A 12. LICENSEE CONTACT FOR THIS LER LICENSEE CONTACT TELEPHONE NUMBER (Include Area Code) Paul F. Czaya (305) 246-7150 13. COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT CAUSE SYSTEM COMPONENT MANU* REPORTABLE CAUSE SYSTEM COMPONENT MANU-REPORTABLE FACTURER TOEPIX , FACTURER TOEPIX 14. SUPPLEMENTAL REPORT EXPECTED 15. EXPECTED MONTH DAY YEAR DYES (If yes,. complete 15. EXPECTED SUBMISSION DATE) [{]NO SUBMISSION DATE ABSTRACT (Limit to 1400 spaces, i._e., approximately 15 single-spaced typewritten lines) On February 8, 2016 at approximately 0147 hours, during a surveillance test, control room indications identified that 3B Emergency Containment Cooler (ECC) fan tripped. Troubleshooting found the control power fuse for the fan's power supply breaker was loose in its fuse holder. Investigation revealed that the fuse holder clips had been widened during work activities associated with the installation of the new bre.aker during the prior Unit3 refueling and maintenance outage. The most probable cause of the loose fuse was improper insertion.
| |
| In addition, the installation procedure did not validate fuse holder gap, fuse alignment, and fuse tightness after its last removal and insertion prior to placing the new breaker in service. Inadequate contact during the surveillance .test caused the fan trip. The 3B ECC would not have reliably met its safety function mission time and so was determined to be inoperable for approximately 72 days exceeding the 72 hour Technical Specification allowed outage time. Corrective actions include: 1) The fuse holder clips were adjusted to provide a tight fit. 2) A review determined additional similar breakers will be inspected for fuse tightness.
| |
| : 3) Future installation and preventive maintenance of similar breakers will check for fuse tightness and correct if necessary.
| |
| Safety significance is considered low based on a risk assessment showing Incremental Conditional Core Damage Probability and Incremental Conditional Large Early Release Probability are below the NRC acceptance for minimal risk impact. -NRC FORM 366 (11*2015)
| |
| Page 2 of 3 NRC FORM 366A (11-2015) . U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET Estimated burden per response to comply with this mandatory collection request: 80 hours. Reported lessons learned are incorporated into the licensing process and fed back to industry.
| |
| Send comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office bf Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRG may not conduct or sponsor, and a person is not required to respond to, the information collection.
| |
| : 1. FACILITY NAME 2. DOCKET NUMBER 3. LER NUMBER I TW"key Poillt Unit.3 I 05000-I 250 Cl NUMBER NO. I YEAR SEQUENTIAL REV 001 1-0 NARRATIVE DESCRIPTION OF THE EVENT On February 8, 2016 at approximately 0147 hours, during a surveillance test, control room indications identified that 3B Emergency Containment Cooler (ECC) fan [BK, FAN] tripped. Troubleshooting found that the control power fuse [BK, FAN, FU] for the fan's power supply breaker [BK, FAN, BKR] was loose in its fuse holder. The fuse would easily spin inside its fuse holder. Investigation determined that the fuse holder clips had been widened during work activities associated with the installation of the new breaker for the 3B ECC during the prior Unit 3 refueling and maintenance outage. The loose control power fuse caused the 3B ECC to be inoperable for approximately 72 days exceeding the Technical Specification (TS) 3.6.2.2, Action 'a' allowed outage time of 72 hours and the resultant shutdown requirements for one inoperable ECC. Because the inoperability of the 3B ECC was not recognized at the time, the actions required by TS 3.6.2.2, Action 'a' were not taken, which is reportable in accordance with 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by the TS. CAUSE OF THE EVENT The most probable cause of the loose fuse was improper insertion.
| |
| In addition, the installation procedure did not validate fuse holder gap, fuse alignment, and fuse tightness after its last removal and insertion prior to placing the new breaker in service .. Inadequate contact during the surveillance test caused the fan trip. ANALYSIS OF THE EVENT The ECC System consists of three fan cooling units; each consisting of a motor, fan, bare tube cooling coil, instrumentation and controls.
| |
| The ECCs, in conjunction with the Containment Spray System (CSS), prevent containment pressure and temperature from exceeding the values calculated in the containment loss of coolant accident (LOCA) analysis and the main steam line break (MSLB) accident analysis, and maintain containment atmosphere below the structural design pressure and temperature.
| |
| Two ECCs (3A and 3C) are automatically initiated via the sequencer on a safety injection (SI) signal. The 3B ECC will start on the failure of either 3A or 3C ECC to start and run. The removal of heat and moisture from the containment is accomplished by recirculating the containment air/vapor mixture to the outside* of the ECC coils by the fan. Heat is then absorbed by the Component Cooling Water (CCW) System which is circulating through the ECC coils. The condensed moisture is drained to the containment sump. The CCW inlet valves to each ECC unit remain open during both normal operation and after SI signal initiation.
| |
| The outlet valves are closed during normal operation, but are opened upon start of the associated ECC unit. The outlet valve is controlled by a solenoid valve powered from the same 3B ECC breaker. The NRC FORM 366A (11-2015)
| |
| NRC FORM 366A (11-2015)
| |
| : 1. FACILITY NAME Turkey Point Unit 3 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET 2. DOCKET NUMBER I 05000-1 250 Page 3 of 3 U.S. NUCLEAR REGULAT,ORY COMMISSION
| |
| : 3. LER NUMBER r:::-:1 NUMBER NO I YEAR. SEQUENTIAL REV LJ*I 001 control circmt tor the solenoid valve is designed such that a loss ot power will result m the closure of the outlet valve. Therefore, if the control power fuse for the 3B ECC breaker were to blow or come loose, then it would result in the failure of the fan to start or remain running and failure of the outlet valve to open or remain open. As a result, the 3B ECC would not have relia_bly met its safety function mission time. ANALYSIS OF SAFETY SIGNIFICANCE The safety significance of having the 3B ECC inoperable for approximately 72 days was determined to be low. A risk assessment shows Incremental Conditional Core Damage Probability and Incremental Conditional Large Early Release are bel'ow the NRC acceptance criteria for minimal risk impact. CORRECTIVE ACTIONS Corrective actions are in accordance with Condition Report 2108256 and include: 1. The fuse holder clips on the 3B ECC breaker were adjusted to provide a tight fit. 2. A review of the operating and test history of recently replaced similar breakers on Units 3 and 4 was performed.
| |
| As a result, certain breakers were identified and scheduled for a contingency inspection of fuse tightness.
| |
| : 3. Future installations and preventative maintenance of similar breakers will check fuse tightness and correct if necessary.
| |
| ADDITIONAL INFORMATION Codes are shown in the format [IEEE system identifier, component function identifier, second component function identifier (if appropriate)].
| |
| FAILED COMPONENTS IDENTIFIED:
| |
| None PREVIOUS SIMILAR EVENTS: None NRG FORM 366A (11-2015)
| |
| * FPL .. U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555-0001 Re: Turkey Point Unit 3 Docket No. 50-250 Reportable Event: 2016-001-00 Date of Event: February 8, 2016 L-2016-071 10 CFR § 50.73 APR 0 7 2016 Loose Breaker Control Power Fuse Caused the 3B Emergency Containment Cooler to be Inoperable Longer Than Allowed by Technical Specifications The attached Licensee Event Report 05000250/2016-001-00 is submitted pursuant to 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by the Technical Specifications.
| |
| If there are any questions, please call Mr. Mitch Guth at 305-246-6698.
| |
| Sincerely,
| |
| /fhomas 1;ummers Vice President Turkey Point Nuclear Plant Attachment cc: Regional Administrator, USNRC, Region II Senior Resident Inspector, USNRC, Turkey Point Nuclear Plant Florida Power & Light Company 9760 SW 344th St., Homestead, FL 33035 NRC FORM366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 (11-2015) l:stimated burden per response to comply with this mandatory collection request 80 hours. '.'1fa** Reported lessons learned are incorporated*
| |
| into the licensing process and fed back to indusiry.
| |
| t Send comments regarding burden estimate to the FOIA, Privacy and Information Collections LICENSEE EVENT REPORT (LER) Branch. (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by ** .. , ...... : .. :* internet e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and (See Page 2 for required number of Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, digits/characters for each block) DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRG may not conduct or sponsor, and a person is not required to respond to, the information collection.
| |
| : 1. FACILITY NAME 2. DOCKET NUMBER 3. PAGE Turkey Point Unit 3 05000 250 1 OF 3 4. TITLE Loose Breaker Control Power Fuse Caused 3B Emergency Containment Cooler to be Inoperable Longer Than Allowed 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 MONTH DAY YEAR NUMBER NO. 05000 FACILITY NAME DOCKET NUMBER 2 8 2016 2016 -001 -00 4 7 2016 05000 9. OPERATING MODE 11. THIS REPORT IS SUBMITTED-PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) D 20.2201(b)
| |
| D 20.2203(a)(3)(i)
| |
| * D 50.73(a)(2)(ii)(A)
| |
| D 50.73(a)(2)(yiii)(A) 1 D 20.2201(d)
| |
| D 2*0.2203(a)(3)(ii)
| |
| D 50.73(a)(2)(ii)(B)
| |
| D 50.73(a)(2)(viii)(B)
| |
| D 20.2203(a)(1)
| |
| D 20.2203(a)(4)
| |
| D so.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)(ii)
| |
| D 50.36(c)(1)(ii)(A)
| |
| D 50.73(a)(2)(v)(A)
| |
| D 73.71(a)(4)
| |
| D 20.2203(a)(2)(iii)
| |
| _ D so.36(c)(2)
| |
| 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(a)(1) 100 D 20.2203(a)(2)<v>
| |
| D 50.73(a)(2)(i)(A)
| |
| D 50.73(a)(2)(v)(D)
| |
| D 73.77(a)(2)(i)
| |
| D 20.2203(a)(2)(vi)
| |
| [{] 50.73(a)(2)(i)(B)
| |
| D 50.73(a)(2)(vii)
| |
| D 73.77(a)(2)(ii)
| |
| D 50.73(a)(2)(i)(C)
| |
| D OTHER Specify in Abstract below or in NRC Form 366A 12. LICENSEE CONTACT FOR THIS LER LICENSEE CONTACT TELEPHONE NUMBER (Include Area Code) Paul F. Czaya (305) 246-7150 13. COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT CAUSE SYSTEM COMPONENT MANU* REPORTABLE CAUSE SYSTEM COMPONENT MANU-REPORTABLE FACTURER TOEPIX , FACTURER TOEPIX 14. SUPPLEMENTAL REPORT EXPECTED 15. EXPECTED MONTH DAY YEAR DYES (If yes,. complete 15. EXPECTED SUBMISSION DATE) [{]NO SUBMISSION DATE ABSTRACT (Limit to 1400 spaces, i._e., approximately 15 single-spaced typewritten lines) On February 8, 2016 at approximately 0147 hours, during a surveillance test, control room indications identified that 3B Emergency Containment Cooler (ECC) fan tripped. Troubleshooting found the control power fuse for the fan's power supply breaker was loose in its fuse holder. Investigation revealed that the fuse holder clips had been widened during work activities associated with the installation of the new bre.aker during the prior Unit3 refueling and maintenance outage. The most probable cause of the loose fuse was improper insertion.
| |
| In addition, the installation procedure did not validate fuse holder gap, fuse alignment, and fuse tightness after its last removal and insertion prior to placing the new breaker in service. Inadequate contact during the surveillance .test caused the fan trip. The 3B ECC would not have reliably met its safety function mission time and so was determined to be inoperable for approximately 72 days exceeding the 72 hour Technical Specification allowed outage time. Corrective actions include: 1) The fuse holder clips were adjusted to provide a tight fit. 2) A review determined additional similar breakers will be inspected for fuse tightness.
| |
| : 3) Future installation and preventive maintenance of similar breakers will check for fuse tightness and correct if necessary.
| |
| Safety significance is considered low based on a risk assessment showing Incremental Conditional Core Damage Probability and Incremental Conditional Large Early Release Probability are below the NRC acceptance for minimal risk impact. -NRC FORM 366 (11*2015)
| |
| Page 2 of 3 NRC FORM 366A (11-2015) . U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET Estimated burden per response to comply with this mandatory collection request: 80 hours. Reported lessons learned are incorporated into the licensing process and fed back to industry.
| |
| Send comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office bf Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRG may not conduct or sponsor, and a person is not required to respond to, the information collection.
| |
| : 1. FACILITY NAME 2. DOCKET NUMBER 3. LER NUMBER I TW"key Poillt Unit.3 I 05000-I 250 Cl NUMBER NO. I YEAR SEQUENTIAL REV 001 1-0 NARRATIVE DESCRIPTION OF THE EVENT On February 8, 2016 at approximately 0147 hours, during a surveillance test, control room indications identified that 3B Emergency Containment Cooler (ECC) fan [BK, FAN] tripped. Troubleshooting found that the control power fuse [BK, FAN, FU] for the fan's power supply breaker [BK, FAN, BKR] was loose in its fuse holder. The fuse would easily spin inside its fuse holder. Investigation determined that the fuse holder clips had been widened during work activities associated with the installation of the new breaker for the 3B ECC during the prior Unit 3 refueling and maintenance outage. The loose control power fuse caused the 3B ECC to be inoperable for approximately 72 days exceeding the Technical Specification (TS) 3.6.2.2, Action 'a' allowed outage time of 72 hours and the resultant shutdown requirements for one inoperable ECC. Because the inoperability of the 3B ECC was not recognized at the time, the actions required by TS 3.6.2.2, Action 'a' were not taken, which is reportable in accordance with 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by the TS. CAUSE OF THE EVENT The most probable cause of the loose fuse was improper insertion.
| |
| In addition, the installation procedure did not validate fuse holder gap, fuse alignment, and fuse tightness after its last removal and insertion prior to placing the new breaker in service .. Inadequate contact during the surveillance test caused the fan trip. ANALYSIS OF THE EVENT The ECC System consists of three fan cooling units; each consisting of a motor, fan, bare tube cooling coil, instrumentation and controls.
| |
| The ECCs, in conjunction with the Containment Spray System (CSS), prevent containment pressure and temperature from exceeding the values calculated in the containment loss of coolant accident (LOCA) analysis and the main steam line break (MSLB) accident analysis, and maintain containment atmosphere below the structural design pressure and temperature.
| |
| Two ECCs (3A and 3C) are automatically initiated via the sequencer on a safety injection (SI) signal. The 3B ECC will start on the failure of either 3A or 3C ECC to start and run. The removal of heat and moisture from the containment is accomplished by recirculating the containment air/vapor mixture to the outside* of the ECC coils by the fan. Heat is then absorbed by the Component Cooling Water (CCW) System which is circulating through the ECC coils. The condensed moisture is drained to the containment sump. The CCW inlet valves to each ECC unit remain open during both normal operation and after SI signal initiation.
| |
| The outlet valves are closed during normal operation, but are opened upon start of the associated ECC unit. The outlet valve is controlled by a solenoid valve powered from the same 3B ECC breaker. The NRC FORM 366A (11-2015)
| |
| NRC FORM 366A (11-2015)
| |
| : 1. FACILITY NAME Turkey Point Unit 3 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET 2. DOCKET NUMBER I 05000-1 250 Page 3 of 3 U.S. NUCLEAR REGULAT,ORY COMMISSION
| |
| : 3. LER NUMBER r:::-:1 NUMBER NO I YEAR. SEQUENTIAL REV LJ*I 001 control circmt tor the solenoid valve is designed such that a loss ot power will result m the closure of the outlet valve. Therefore, if the control power fuse for the 3B ECC breaker were to blow or come loose, then it would result in the failure of the fan to start or remain running and failure of the outlet valve to open or remain open. As a result, the 3B ECC would not have relia_bly met its safety function mission time. ANALYSIS OF SAFETY SIGNIFICANCE The safety significance of having the 3B ECC inoperable for approximately 72 days was determined to be low. A risk assessment shows Incremental Conditional Core Damage Probability and Incremental Conditional Large Early Release are bel'ow the NRC acceptance criteria for minimal risk impact. CORRECTIVE ACTIONS Corrective actions are in accordance with Condition Report 2108256 and include: 1. The fuse holder clips on the 3B ECC breaker were adjusted to provide a tight fit. 2. A review of the operating and test history of recently replaced similar breakers on Units 3 and 4 was performed.
| |
| As a result, certain breakers were identified and scheduled for a contingency inspection of fuse tightness.
| |
| : 3. Future installations and preventative maintenance of similar breakers will check fuse tightness and correct if necessary.
| |
| ADDITIONAL INFORMATION Codes are shown in the format [IEEE system identifier, component function identifier, second component function identifier (if appropriate)].
| |
| FAILED COMPONENTS IDENTIFIED:
| |
| None PREVIOUS SIMILAR EVENTS: None NRG FORM 366A (11-2015)}}
| |