Information Notice 1999-13, Insights from NRC Inspections of Low-and Medium-Voltage Circuit Breaker Maintenance Programs
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555-0001
April 29, 1999
NRC INFORMATION NOTICE 99-13: INSIGHTS FROM NRC INSPECTIONS OF LOW- AND
MEDIUM-VOLTAGE CIRCUIT BREAKER
MAINTENANCE PROGRAMS
Addressees
All holders of operating licenses for nuclear power reactors.
Purpose
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice to summarize
observations made and insights gained during inspections of licensee circuit breaker
maintenance programs. It is expected that recipients will review the information for applicability
to their facilities and consider actions, as appropriate. However, suggestions contained in this
information notice are not NRC requirements; therefore, no specific action or written response
is required.
Description of Circumstances
Because of concerns about the reliability of safety-related medium-voltage (4-kV to 15-kV) and
low-voltage (600-V and below) power circuit breakers, the NRC inspected the circuit breaker
maintenance programs at eight nuclear power plant sites in 1998, using Temporary Instruction
(TI) 2515/137, Revision 1, "Inspection of Medium-Voltage and Low-Voltage Power Circuit
Breakers," issued on March 9, 1998. For more detailed information, the individual inspection
reports are available through the NRC Public Document Room. Attachment I lists the
inspection reports and their accession numbers.
The TI inspections confirmed that the programs were generally adequate. However, observations made at several of the plants inspected indicate that licensee programs have
several areas in common in which improvement may be desirable. In addition, in a few
instances certain aspects of programs did not meet NRC requirements, and violations were
cited. Licensees for the inspected plants have already taken steps to address many of the
areas of concern identified by the inspections. This notice was developed so that all licensees
may take advantage of insights gained from the inspections when considering circuit breaker
maintenance program improvements.
Discussion
Significant observations from the TI inspections are described below and have been
categorized as follow: (1) general programmatic issues, (2) preventive maintenance, i9042k8 o0l0
3 (EEDEZq9Dt
IN 99-13 April 29, 1999 (3) licensee/vendor interface, (4) control voltage calculations, and (5) operating experience
review. However, licensees are encouraged to review the inspection reports for detailed
findings and their resolutions.
I. General Programmatic Issues
Licensee preventive maintenance procedures and practices did not always reflect all of the
applicable vendor recommendations or industry operating experience, and when licensees
deviated from such recommendations and operating experience there was often no
documented basis or rationale given. Adherence to vendor recommendations is not a
regulatory requirement, but a sound engineering basis for such deviations is Important, and
should be performed in consultation with the vendor when possible, to ensure that valuable
vendor information is not overlooked.
Storage, shelf life, environment, segregation, and issuance of lubricants and cleaning materials
were not well controlled. Some licensees had not identified shelf lives for circuit breaker
lubricants and cleaning agents or solvents.
Individual breakers at some plants either did not come with or were not given unique identifiers.
Some licensees were not aware that group or series identifiers, such as shop order numbers, were not unique. Some licensees did not record both the breaker serial number, when present, or the cubicle number in maintenance records to allow for tracking of breaker location, performance, and maintenance history.
At most plants, the racking of breakers In and out of the cubicle (and local operation when
required) was the job of operations department personnel rather than circuit breaker
maintenance personnel. However, operations department training and/or procedures did not
always cover breaker position verification or functional testing in the connected position (closing
the breaker and running load equipment, when permitted by plant conditions). Training
operations department personnel to verify proper indications, closing spring recharging, and
restoration of all electrical and mechanical interfaces and interlocks, and cycling the breaker
after it is racked in, could result in fewer failures to close on demand.
II. Preventive Maintenance
Preventive maintenance was not always performed with the frequency recommended by the
original equipment manufacturer (OEM), and licensees had no documented justification for
deviating from that frequency.
Maintenance procedures sometimes did not cover inspection for specific problems identified in
industry operating experience. Some licensees stated that they covered such items in training, but specific items in question were seldom explicitly addressed in lesson plans.
IN 99-13 April 29, 1999 Ill. Licenseeh/endor Interface
The TI inspections revealed that circuit breaker and switchgear vendor manuals were often not
kept current, and the programs for periodic recontact provided for in Generic Letter (GL) 90-03 were ineffective in obtaining revisions or updates to vendor manuals, or other pertinent
technical information.
Some licensees identified areas in which improvements could be made to vendor interface
programs, including (1) periodic review of plant equipment to ensure that lists of key safety- related equipment are current, (2) establishing organizational and procedural interfaces and
links to ensure that vendor interface personnel are kept informed of equipment changes or
modifications, (3) establishing personal contact with the appropriate vendor personnel,
(4) substantial involvement in the process by technically knowledgeable personnel, and
(5) periodic comprehensive reconciliation with the vendor of lists of equipment and related
technical publications or documentation.
IV. Control Voltaae Calculations
The TI inspections revealed that a few licensees had not performed the circuit breaker control
voltage calculations based on as-built systems. In some cases where calculations were
performed several discrepancies were identified, including (1) not starting with the minimum
battery voltage; (2) using an incorrect minimum battery voltage that did not take into account
loading, state of discharge, and/or aging factors; (3) using incorrect current paths, cable
lengths, conductor sizes, and/or ohms/foot values to determine overall cable resistance;
(4) calculation of cable conductor resistance using ambient temperature values, but neglecting
temperature rise caused by heat from surrounding cables In a raceway or without having data
to justify the non-conservative lower temperature assumption; and (5) using incorrect loading
values in the final determinations of voltage drops. One licensee, had not translated this design
basis information into test procedures to demonstrate breaker operability (NRC Inspection
Report 50-266/98-13).
V. Operating Experience Review
At most of the plants inspected, weaknesses were observed in the review of operational
experience documents related to low- and medium-voltage circuit breakers. These documents
included NRC information notices (INs); INPO SEE-IN documents or Nuclear Network reports;
and vendor information, such as service information letters, technical bulletins, or service
advisory letters.
The TI inspections revealed instances of industry operating experience information erroneously
determined to be not applicable because of narrowly focused and/or superficial reviews, and
insufficient involvement by technically knowledgeable personnel. Problems generically
applicable to several types of breakers were often not recognized because the plant's breakers
did not have exactly the same model designation as the one used as an example in the
information notice or the vendor technical bulletin.
IN 99-13 April 29, 1999 TI 2515/137, Revision 1, lists 62 NRC information notices and bulletins that deal with problems
with low- and medium-voltage power circuit breakers. As many as one-third of these were
erroneously determined to be not applicable at one or more plants.
Related Generic Communications
IN 98-38, Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections,".
issued on October 15, 1998, alerted licensees to issues identified by reactive NRC inspections
at plants that experienced problems concerning circuit breaker reliability in 1997. The events
discussed in that information notice were the catalyst that prompted the TI inspections of
licensee maintenance programs in 1998.
Conclusion
This information notice requires no specific action or written response. However, recipients are
reminded that they are required to consider industry-wide operating experience (including NRC
information notices) where practical when setting goals and performing periodic evaluations
under Section 50.65, "Requirement for monitoring the effectiveness of maintenance at nuclear
power plants," of Part 50 of Title 10 of the Code of Federal Regulations. If you have any
questions about the information in this notice, please contact one of the technical contacts
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.
Ledyard B. Marsh, Chief
Events Assessment, Generic Communications, and Non-Power Reactors Branch
Division of Regulatory Improvement Programs
Office of Nuclear Reactor Regulation
Technical contacts:
Stephen Alexander, NRR
Amar Pal, NRR
301- 415-2995
301- 415-2760
E-mail: sdaDnrc.cov
E-mail: anDrtnrc.aov
S.K. Mitra, NRR
301- 415-1174
301- 415-2783 E-mail: dlsO-nrc.gov
E-mail: skm1I(nrc.aov
Attachments:
1. Table of NRC TI Inspection Reports
2. List of Recently Issued NRC Information Notices
I -1
'U
Attachment 1
IN 99-13 April 29, 1999 TABLE I - Temporary Instruction 26151137 Inspection Reports
PLANT
REPORT
ISSUE
ACCESSION
NUMBER
DATE
NUMBER
Callaway
50-483/98-15
10/26/98
9810290263 Hatch 1 & 2
50-326/98-08
04/30/98
9805110181 Nine Mile Point 2
50-410/98-18
11/13/98
9811240071 Perry
50-440/98-11
07/16/98
9807220299 Point Beach 1 & 2
50-266/98-13
09/11/98
9809180178 Seabrook
50-443/98-07
09/28/98
9810050116 Sequoyah 1 & 2
5D-327/98-05
06/12/98
9807070138 Waterford 3
50-382/98-13
111/17/98
9811240126
-
4
Attachment 2
April 29, 1999 LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
Information
Date of
Notice No.
Subject
Issuance
Issued to
99-12
Year 2000 Computer Systems
Readiness Audits
4/28/99
All holders of operating licenses
or construction permits for nuclear
power plants
99-11
Incidents Involving the Use of
Radioactive Iodine-131
4/23199
All medical use licensees
97-15, Sup 1 Reporting of Errors and
4/16/99 Changes inLarge-Break/Small- Break Loss-of-Coolant Evaluation
models of Fuel Vendors and
Compliance with 10 CFR 50.46(a)(3) certified that fuel
from the reactor
All holders of operating licensees
for nuclear power reactors, except
those who have permanently
cease operations and have
has been permanently removed
99-10
99-09
99-08
99-07 Degradation of Prestressing
4/13/99
Tendon Systems in Prestressed
Concrete Containments
Problems Encountered When
3/24/99
Manually Editing Treatment Data
on The Nucletron Microselectron-HDR
(New) Model 105.999 Urine Specimen Adulteration
4/11/99 Fire Protection Preaction
3/22/99
Sprinkler System Deluge Valve
Failures and Potentials Testing
Deficiencies
All holders of Ols for nuclear
power reactors
All medical licensees authorized
to conduct high-dose-rate (HDR)
remote after loading
brachytherapy treatments
All holders of operating licensees
For nuclear power reactors and
licensees authorized to possess
or use formula quantities of
strategic special nuclear material
(SSNM)
All NRC licensees
OL = Operating License
CP = Construction Permit
IN 99-13 April 29, 1999 TI 2515/137, Revision 1, lists 62 NRC information notices and bulletins that deal with problems
with low- and medium-voltage power circuit breakers. As many as one-third of these were
erroneously determined to be not applicable at one or more plants.
Related Generic Communications
IN 98-38, "Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections,"
issued on October 15, 1998, alerted licensees to issues identified by reactive NRC inspections
at plants that experienced problems concerning circuit breaker reliability in 1997. The events
discussed in that information notice were the catalyst that prompted the TI inspections of
licensee maintenance programs in 1998.
Conclusion
This information notice requires no specific action or written response. However, recipients are
reminded that they are required to consider industry-wide operating experience (including NRC
information notices) where practical when setting goals and performing periodic evaluations
under Section 50.65, "Requirement for monitoring the effectiveness of maintenance at nuclear
power plants," of Part 50 of Title 10 of the Code of Federal Regulations. If you have any
questions about the information in this notice, please contact one of the technical contacts
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.
[Original signed by]
Ledyard B. Marsh, Chief
Events Assessment, Generic Communications, and Non-Power Reactors Branch
Division of Regulatory Improvement Programs
Office of Nuclear Reactor Regulation
Technical contacts:
Stephen Alexander, NRR
Amar Pal, NRR
301- 415-2995
301- 415-2760
E-mail: sdaO-nrc.gov
E-mail: anPDnrc.gov
S.K. Mitra, NRR
301- 415-1174
301- 415-2783 E-mail: dlsO-nrc.aov
E-mail: skm1(Dnrc.aov
Attachments:
1. Table of NRC TI Inspection Reports
2. List of Recently Issued NRC Information Notices
DOCUMENT NAME: G:\\DLS\\BKRINSP.IN - See previous concurrence
To receive a copy of this document, Indicate in the box C=Copy wfo attachment/enclosure E=Copy with attachment/enclosure N = No copy
OFFICE
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14/21/99
OFFICIAL RECORD COPY
4 IN 99-xx
April xx, 1999 TI 2515/137, Revision 1, lists 62 NRC information notices and bulletins that deal with problems
with low- and medium-voltage power circuit breakers. As many as one-third of these were
erroneously determined to be not applicable at one or more plants.
Related Generic Communications
IN 98-38, "Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections,"
issued on October 15, 1998, alerted licensees to issues identified by reactive NRC inspections
at plants that experienced problems concerning circuit breaker reliability in 1997. The events
discussed in that information notice were the catalyst that prompted the TI inspections of
licensee maintenance programs in 1998.
Conclusion
This information notice requires no specific action or written response. However, recipients are
reminded that they are required to consider industry-wide operating experience (including NRC
information notices) where practical when setting goals and performing periodic evaluations
under Section 50.65, "Requirement for monitoring the effectiveness of maintenance at nuclear
power plants," of Part 50 of Title 10 of the Code of Federal Regulations. If you have any
questions about the information in this notice, please contact one of the technical contacts
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.
Ledyard B. Marsh, Chief
Events Assessment, Generic Communications, and Non-Power Reactors Branch
Division of Regulatory Improvement Programs
Office of Nuclear Reactor Regulation
Technical contacts:
Stephen Alexander, NRR
301- 415-2995 E-mail: sda(nrc.aov
Amar Pal, NRR
301- 415-2760
E-mail: anDLnrc.gov
David Skeen, NRR
301- 415-1174 E-mail: dIs(Dnrc.aov
S.K. Mitra, NRR
301- 415-2783 E-mail: skm10_nrc.gov
Attachments:
1. Table of NRC TI Inspection Reports
2. List of Recently Issued NRC Information Notices
DOCUMENT NAME: G:\\DLS\\BKRINSP.IN - See previous concurrence
To receive a copy of this document, indicate in the box
U=Gopy wo attacnmenienclosure t=Copy witn atnacnmenuenci
OFFICE
PECB:DRPM I
TechEd
C:EELB
DC:PECB
NAME
DSkeen*
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LMarsh*
DATE
4/21/99
04/09/99
4/16/99
.Yi
9,
4/21/99 DSUre N = NO COPY
OFFICIAL RECORD COPY
A \\
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IN 99-XX
April xx, 1999 Related Generic Communications
IN 98-38, "Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections,"
issued on October 15, 1998, alerted licensees to issues identified by reactive NRC inspections
at plants that experienced problems concerning circuit breaker reliability in 1997. The events
discussed in that information notice were the catalyst that prompted the TI inspections of
licensee maintenance programs in 1998.
Conclusion
This information notice requires no specific action or written response. However, recipients are
reminded that they are required to consider industry-wide operating experience (including NRC
information notices) where practical when setting goals and performing periodic evaluations
under Section 50.65, "Requirement for monitoring the effectiveness of maintenance at nuclear
power plants," of Part 50 of Title 10 of the Code of Federal Regulations. If you have any
questions about the information in this notice, please contact one of the technical contacts listed
below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.
Ledyard B. Marsh, Events Assessment, Generic Communications,
6- and Non-Power Reactors Branch
Division of Regulatory Improvement Programs
Office of Nuclear Reactor Regulation
Technical contacts:
Stephen Alexander, NRR
Amar Pal, NRR
301- 415-2995
301- 415-2760
E-mail: sda~nrc.gov
E-mail:anp@nrc.gov
S.K. Mitra, NRR
301- 415-1174
301- 415-2783 E-mail: dls@nrc.gov
E-mail:skm1@nrc.gov
Attachments: 1. Table of NRC TI Inspection Reports
2. List of Recently Issued NRC Information Notices
DOCUMENT NAME: G:\\DLS\\BKRINSP.IN
To receive a copy of this document, indicate in the box C=Copy w/o attachmentlenclosure ECopy with attachment/enclosure N = No copy
lOFFICE
PECB:DRPM l
TechEd
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OFFICIAL RECORD COPY
IN 99-XX
April xx, 1999 Related Generic Communications
IN 98-38, "Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections,"
issued on October 15, 1998, alerted licensees to issues identified by reactive NRC inspections
at plants that experienced problems concerning circuit breaker reliability in 1997. The events
discussed in that information notice were the catalyst that prompted the TI inspections of
licensee maintenance programs in 1998.
Conclusion
This information notice requires no specific action or written response. However, recipients are
reminded that they are required to consider industry-wide operating experience (including NRC
information notices) where practical when selling goals and performing periodic evaluations
under Section 50.65, "Requirement for monitoring the effectiveness of maintenance at nuclear
power plants," of Part 50 of Title 10 of the Code of Federal Regulations. If you have any
questions about the information in this notice, please contact one of the technical contacts listed
below or the appropriate Office of Nuclear Reactor Re ulation (NRR) project manager.
HeI
f eA.
Dalid . MOEliews, Director
Division
e ulatory Improvement Programs
Office o
uclea-tmor Regulation
Stephen Alexander, NRR
Amar Pal, NRR
301- 415-2995
301- 415-2760
E-mail: sdaenrc.gov
E-mail:anp@nrc.gov
Technical contacts:
David Skeen, NRR
301- 415-1174 E-mail: dls@nrc.gov
S.K. Mitra, NRR
301- 415-2783 E-mail:skml@nrc.gov
Attachments: 1. Table of NRC TI Inspection Reports
2. List of Recently Issued NRC Information Notices
DOCUMENT NAME: G:XDLS\\BKRINSP.IN
coov of this document. indicate In the box C=Coov w/o attachmentlenclosure E=Coov with attachment/enclosure N = No coDY
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