VY

Attachment 3

IN 95-19
March 22, 1995
Page 1 of 1
LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
Information Date of
Notice No. Subject Issuance Issued to
95-18 Potential Pressure-Locking 03/15/95 All holders of OLs or CPs
of Safety-Related Power- for nuclear power reactors.
Operated Gate Valves
95-17 Reactor Vessel Top Guide 03/10/95 All holders of OLs or CPs
and Core Plate Cracking
95-16 Vibration Caused by 03/09/95 All holders of OLs or CPs
Increased Recirculation for boiling water reactors.
Flow in a Boiling Water
Reactor
95-15 Inadequate Logic Testing 03/07/95 All holders of OLs or CPs
of Safety-Related Circuits for nuclear power reactors.
95-14 Susceptibility of Con- 02/28/95 All holders of OLs or CPs
tainment Sump Recircula- for nuclear power reactors.
tion Gate Valves to
Pressure Locking
95-13 Potential for Data 02/24/95 All holders of OLs or CPs
Collection Equipment to for nuclear power reactors.
Affect Protection System
Performance
95-12 Potentially Nonconforming 02/21/95 All holders of OLs or CPs
Fasteners Supplied by for nuclear power reactors.
A&G Engineering II, Inc.
95-11 Failure of Condensate 02/24/95 All holders of OLs or CPs
Piping Because of Erosion/ for nuclear power reactors.
Corrosion at a Flow-
Straightening Device
95-10 Potential for Loss of 02/10/95 All holders of OLs or CPs
Supp. 1 Automatic Engineered for nuclear power reactors.

Safety Features
Actuation

OL = Operating License
CP = Construction Permit


IN 95-xx
January xx, 1995

Page 2 of 2

This information notice requires no specific action or written response. 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.

Brian K. Grimes, Director
Division of Project Support
Office of Nuclear Reactor Regulation

Technical contacts: S$. Rudisail, Region II
(404) 331-5582

M. B. Shymlock, Region II
(404) 331-5596

S. K. Mitra, NRR
(301) 504-2783

Attachments:
1. Figure 1 *
2. GE SAL 303.0 Ute
3. List of Recently Issued NRC Information Notices Ww
us on tt4 |
OECB:DOPS:NRR* | RPB:ADM* ceve:pe (ue —_| cyeeve:ve/~<f/ AI
7 Cony
DCKirkpatrick BCalure ,Tech Ed { SKMitra CEBerlinger |
12/22/94 12/28/94 1/23/95 1/B/95
Yos?_| REG IL Lt ‘4 SC/OECB:DOPS:NRR
AA
SRudisail mpshymok2 07" EFGoodwin G>
Za
01/26/95 0196/95 0124/95 |
OECB:DOPS:NRR C/OECB:DOPS:NRR D/DOPS :NRR |
RJKiessel AEChaffee BKGrimes |
01 95 O1/ /95 O1/  /95 |

* See previous concurrences


IN 95-XX
March xx, 1995
Page 2 of 2

Discussion

On April 6, 1989, GE Switchgear Operation issued service advisory letter (SAL)
303.0, which dealt with the possibility that the cutoff switch actuator could
crack and break and lead to breaker coil burnout. The text of SAL 303.0 is
shown in Attachment 2. Although these cutoff switches had a different
failure mode and were installed on different breaker models (Models AKR(U) 30s
and AK(U) 25-1), the cutoff switch in question was the same part (p/n 622 C
595 G1) as the one that caused the AK2-25 breaker failure at St. Lucie,

Init 2.

The majority of the reactor trip breaker failures at power reactors have been
caused by problems with relatively small electrical subcomponents in the
breaker assembly, rather that the malfunction of the main breaker mechanism
itself. The failure of the cutoff switch in the trip breaker at St Lucie is
another example of a subcomponent failure resulting in the failure of a trip
breaker. It follows that the frequency of reactor trip breaker failures could
be significantly reduced if these smal] component problems could be eliminated
by careful inspection and maintenance.

This information notice requires no specific action or written response. 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.

Brian K. Grimes, Director
Division of Project Support
Office of Nuclear Reactor Regulation

Technical contacts: S. Rudisail, Region II S. K. Mitra, NRR
(404) 331-5582 (301) 504-2783

M. B. Shymlock, Region II
(404) 331-5596
Attachments:
1. Figure 1
2. GE SAL 303.0
3. List of Recently Issued NRC Information Notices
DOCUMENT NAME: S:\DOPS SEC\BREAKER *See previous concurrence

OECB:DOPS :NRR* RPB: ADM EELB:DE C/EELB:DE
DCKirkpatrick BCalure, Tech Ed* | SKMitra* CEBer] inger*
12/22/94 12/28/94 01/23/95 01/23/95

RII (via e-mail) | RII (via e-mail) SC/OECB:DOPS:NRR | OECB:DOPS:NRR
SRudisail* MBShym1ok* EFGoodwin* RJKiessel*
01/25/95 01/25/95 01/26/95 02/01/95
C/OECB:DOPS:NRR D/DOPS:NRR
AEChaffee* BKGrimes
03/11/95



j Y
V IN 95-19
March 22, 1995
Page 2 of 2

Discussion

On April 6, 1989, GE Switchgear Operation issued service advisory letter (SAL)
303.0, which dealt with the possibility that the cutoff switch actuator could
crack and break and lead to breaker coil burnout. The text of SAL 303.0 is
shown in Attachment 2. Although these cutoff switches had a different
failure mode and were installed on different breaker models (Models AKR(U) 30s
and AK(U) 25-1), the cutoff switch in question was the same part (p/n 622 C
0S 61) as the one that caused the AK2-25 breaker failure at St. Lucie,

Init 2.

The majority of the reactor trip breaker failures at power reactors have been
caused by problems with relatively small electrical subcomponents in the
breaker assembly, rather that the malfunction of the main breaker mechanism
itself. The failure of the cutoff switch in the trip breaker at St Lucie is
another example of a subcomponent failure resulting in the failure of a trip
breaker. The frequency of reactor trip breaker failures could be reduced if
these small component problems were made less likely by appropriate inspection
and maintenance.

This information notice requires no specific action or written response. 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.

Brian kK. Grimeeinal slanedkhy Brian K. Grimes:

Division of Project Support
Office of Nuclear Reactor Regulation

Technical contacts: S. Rudisail, Region II S. K. Mitra, NRR
(404) 331-5582 (301) 415-2783

M. B. Shymlock, Region II
(404) 331-5596
Attachments:
1. Figure 1
2. GE SAL 303.0
3. List of Recently Issued NRC Information Notices
DOCUMENT NAME: $:\DOPS SEC\95-19.IN *See previous concurrence

OECB:DOPS:NRR* RPB:ADM EELB:DE C/EELB:DE
OCKirkpatrick BCalure, Tech Ed* | SKMitra* CEBerlinger*
12/22/94 12/28/94 01/23/95 01/23/95

RII (via e-mail) | RII (via e-mail) SC/OECB:DOPS:NRR_| OECB:DOPS:NRR
SRudisail* MBShymlok* EFGoodwin* RJKiessel*
01/25/95 2 A 01/26/95 | 02/01/95

C/OECB:DOPS :NRR
AEChaffee*
03/11/95

OFFICIAL RECORD COPY


IN 95-xx
January xx, 1995
Page 2 of 2

Discussion

On April 6, 1989, GE Switchgear Operation issued service advisory letter (SAL)
303.0, which dealt with the possibility that the cutoff switch actuator could
crack and break and lead to breaker coil burnout. A copy of SAL 303.0 is
attached. Although these cutoff switches had a different failure mode and
were installed on different breaker models (Models AKR(U) 30s and AK(U) 25-1),
the cutoff switch in question was the same part (p/n 622 C 505 G1) as the one
that caused the AK2-25 breaker failure at St. Lucie, Unit 2.

The majority of the reactor trip breaker failures at power reactors have been
caused by problems with relatively small electrical subcomponents in the
breaker assembly, rather that the malfunction of the main breaker mechanism
itself. The failure of the cutoff switch in the trip breaker at St Lucie is
another example of a subcomponent failure resulting in the failure of a trip
breaker. It follows that the frequency of reactor trip breaker failures could
be significantly reduced if these small component problems could be eliminated
by careful inspection and maintenance.

This information notice requires no specific action or written response. 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.

Brian K. Grimes, Director
Division of Project Support
Office of Nuclear Reactor Regulation

Technical contacts: S. Rudisail, Region II S. K. Mitra, NRR
(404) 331-5582 (301) 504-2783

M. B. Shymlock, Region II
(404) 331-5596

Attachments:

1. Figure 1

2. GE SAL 303.0

3. List of Recently Issued NRC Information Notices

DOCUMENT NAME: G:\DON\BREAKER *See previous concurrence

OECB:DOPS:NRR* RPB: ADM* EELB:DE* C/EELB:DE*
DCKirkpatrick BCalure, Tech Ed_| SKMitra CEBerlinger
12/22/94 12/28/94 01/23/95 01/23/95

RII* (via e-mail) | RII* (via e-mail) SC/OECB:DOPS :NRR*
SRudisail MBShymlok EFGoodwin
01/25/95 01/25/95 01/26/95

OECB:DOPS:NRR C/OECB:DOPS:NRR | D/DOPS:NRR
RUKiessel /¢ | aechaffee BkGrimes



UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555

March 22, 1995

NRC INFORMATION NOTICE 95-19: FAILURE OF REACTOR TRIP BREAKER TO OPEN BECAUSE
OF CUTOFF SWITCH MATERIAL LODGED IN THE TRIP
LATCH MECHANISM

Addressees

All holders of operating licenses or construction permits for nuclear power
reactors.

Purpose

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information
notice to alert addressees to the possible failure of a circuit breaker to
open because of obstruction by material from a subcomponent switch. It is
expected that recipients will review this information for applicability to
their facilities and consider actions, as appropriate, to avoid similar
problems. However, suggestions contained in this information notice are not
NRC requirements; therefore, no specific action or written response is
required.

Description of Circumstances

On July 14, 1994, during the monthly testing of the logic matrix of the
reactor protection system at St. Lucie, Unit 2, a General Electric (GE)

Model AK 2-25 circuit breaker failed to open after operating correctly on
three previous steps of the surveillance procedure. This circuit breaker is
one of eight reactor trip circuit breakers in a one-out-of-two taken twice
reactor trip coincidence logic. Several unsuccessful attempts were made to
open the breaker both electrically and mechanically before the licensee
isolated the breaker as required by the Technical Specifications and shut down
the Unit 2 reactor.

The investigation of the problem revealed that a 6-mm-square [1/4-inch-square]
piece of phenolic material had jammed the circuit breaker trip latch
mechanism, preventing its operation. This piece of phenolic material had
broken off from the breaker cutoff switch (p/n 622 C 505 G1), which is part of
the breaker antipump circuitry. The cutoff switch is mounted in the breaker
assembly above the trip latch mechanism (Figure 1). A screw holding the
cutoff switch had come loose, allowing two halves of the switch to separate,
become misaligned, and break during the previous circuit breaker operation.

The licensee inspected the remaining Unit 2 trip circuit breakers as well as
the similar motor generator set output breakers. No additional loose screws
were found on the cutoff switch mountings. The licensee has incorporated the
inspection of the cutoff switch phenolic block and screw into the maintenance
procedures for Units 1 and 2.

ssosieos7e «= POR: EVE Notice 95 Or 950372
u Tole a i((


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1. Contents of GE Service Advisory Letter 303.0

2. List of Recently Issued NRC Information Notices

OECB:DOPS:NRR RPB:ADM

EELB:DE

C/EELB:DE

DCKirkpatrickACKe) 3 (ano sTech Ed

SKMitra

CEBerlinger

12/22/94 12L25/94

O1/ 95

REG II REG II

SC/OECB:DOPS :NRR

SRudisail MBShym] ok

EFGoodwin

O1/ = /95 O1/ /95

OECB:DOPS:NRR C/OECB:DOPS:NRR

D/DOPS :NRR

O1/ /95

RuKiessel AEChaffee

BkKGrimes

01/  /95 01/ /95

01/ /95



From: Donald C. Kirkpatrick (DCK1)

To: SBR

Date: Wednesday, January 25, 1995 10:43 am
Subject: CONCURNCE W IN:FAILURE OF RX TRIP BREAKR

Steve:

The attached file contains your proposed IN on the failure of the reactor trip
breaker due to foreign material in the latch. Brian Grimes decided that it
should be issued after all. We added some history on previous problems with
the cutoff switch that was the source of the jamming material.

Please review it, concur if possible and pass it on to
Shymlock. Pleace call me at (301) 504-1849 if you need anything else on this.
Thanks,
Don Kirkpatrick, OECB

Files: G:\DON\BREAKER

From: Steven B. Rudisail (SBR)

To: AT1:HMS1:HMS2:WN4:DCK1

Date: Wednesday, January 25, 1995 3:03 pm

Subject: CONCURNCE W IN:FAILURE OF RX TRIP BREAKR

Milton Shymlock and I have reviewed the draft notice and we both concur.

cc: MBS


) VY
to IN 95-xx
March xx, 1995

Page 2 of 2

Discussion

On April 6, 1989, GE Switchgear Operation issued service advisory letter (SAL)
303.0, which dealt with the possibility that the cutoff switch actuator could
crack and break and lead to breaker coil burnout. The text of SAL 303.0 is
shown in Attachment 2. Although these cutoff switches had a different
failure mode and were installed on different breaker models (Models AKR(U) 30s
and AK(U) 25-1), the cutoff switch in question was the same part (p/n 622 C
fos $1) as the one that caused the AK2-25 breaker failure at St. Lucie,

Init 2.

The majority of the reactor trip breaker failures at power reactors have been
caused by problems with relatively small electrical subcomponents in the
breaker assembly, rather that the malfunction of the main breaker mechanism
itself. The failure of the cutoff switch in the trip breaker at St Lucie is
another example of a subcomponent failure resulting in the failure of a trip
breaker. It follows that the frequency of reactor trip breaker failures could
be significantly reduced if these small component problems could be eliminated
by careful inspection and maintenance.

This information notice requires no specific action or written response. 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.

Brian K. Grimes, Director
Division of Project Support
Office of Nuclear Reactor Regulation

Technical contacts: S$. Rudisail, Region II S. K. Mitra, NRR
(404) 331-5582 (301) 504-2783

M. B. Shymlock, Region II
(404) 331-5596
Attachments:
1. Figure 1
2. GE SAL 303.0
3. List of Recently Issued NRC Information Notices
DOCUMENT NAME: G:\DON\BREAKER *See previous concurrence

OECB:DOPS:NRR* RPB: ADM* EELB:DE* C/EELB:DE*
OCKirkpatrick BCalure, Tech Ed | SKMitra CEBerlinger
12/22/94 12/28/94 01/23/95 01/23/95

RII* (via e-mail) | RII* (via e-mail) SC/OECB:DOPS :NRR*
SRudisail MBShymlok EFGoodwin
01/25/95 01/25/95 01/26/95

OECB:DOPS:NRR* C/OECB:DOPS:NRR D/DOPS:NRR
RoKiessel acnlfes 15> | pxarimes
02/01/95

OFFICIAL RECORD COPY


Attachment 2
IN 95-19
March 22, 1995
Page 1 of 1

SUBJECT ELECTRICALLY OPERATED

7
SWITCHGEAR ' AKR 30S AND AKRU 30S BREAKERS
OPERATION 1 AK 25-1 AND AKU 25-1 BREAKERS

SERVICE ADVICE H CUT OF SWITCH BREAKAGE

I

("TAB OTSE 1—SK-NO. 303.0

1 SWGR OPER {

H H

Background

The function of the Cut Off Switch is to interrupt the
closing coil when the breaker is closed.

Problem

On electrically operated AKR(U) 30S and AK(U) 25-1 breakers
manufactured between July 1986 and November 1987 there is a
possibility that the cut off switch actuator may crack and break.
If this occurs, the closing coil may be overheated and burn up
when the breaker is closed.

Recommended Action

GE recommends that the cut off switch actuator on all
affected breakers be visually checked for cracks at the next
regular breaker maintenance / inspection. This includes all
AKR(U) 30S breakers with a Breaker Code Date less than P747+ and
all AK(U) 25-1 breakers with a Breaker Date Code P548+ through
P747+. The Breaker Code Date is on the control voltage nameplate
located to the right of the escutcheon on the breaker frame.

Corrective Action

If a broken or cracked cut off switch is found, contact
Customer Service for a no-charge replacement cut off switch [Part
No. 622C505G1] at:

Mary Hockett Phone: (319) 753-8475
Customer Service 8*673-6475
General Electric Telecopier: (319) 753-5479
PO Box 488 8*673-6479

Burlington, IA 52601

Please have Breaker Serial Numbers and Date Codes when
you contact us.

“PREPARED BY { ISSUED BY T DATE | SUPERSEDES | PAGE 1
H H ‘ISSUE DATED | OF 1
GARY SCHULE ! DON LESNET ! 4-06-89 | (NEW) H


Ww
Vv Attachment 1
IN 95-19
March 22, 1995
Page 1 of 1
FIGURE 1
AK-2 BREAKER FRONT VIEW
SECONDARY DISCONNECTS

{CUTOFF SWITCH PIN 622 C 505 G1)

PIECE OF CUTOFF SWITCH
DROPPED DOWN TO BOTTOM OF
THE TRIP LATCH PREVENTING
THE LATCH FROM ACTUATING



+

2

VY
IN 95-19
March 22, 1995
Page 2 of 2

Discuss jor

On April 6, 1989, GE Switchgear Operation issued service advisory letter (SAL)
303.0, which dealt with the possibility that the cutoff switch actuator could
crack and break and lead to breaker coil burnout. The text of SAL 303.0 is
shown in Attachment 2. Although these cutoff switches had a different
failure mode and were installed on different breaker models (Models AKR(U) 30s
and AK(U) 25-1), the cutoff switch in question was the same part (p/n 622 C
508 1) as the one that caused the AK2-25 breaker failure at St. Lucie,

Init 2.

The majority of the reactor trip breaker failures at power reactors have been
caused by problems with relatively small electrical subcomponents in the
breaker assembly, rather that the malfunction of the main breaker mechanism
itself. The failure of the cutoff switch in the trip breaker at St Lucie is
another example of a subcomponent failure resulting in the failure of a trip
breaker. The frequency of reactor trip breaker failures could be reduced if
these small component problems were made less likely by appropriate inspection
and maintenance.

This information notice requires no specific action or written response. 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. f

Brian K. Grimes, Director
Division of Project Support
Office of Nuclear Reactor Regulation

Technical contacts: S$. Rudisail, Region II S. K. Mitra, NRR
(404) 331-5582 (301) 415-2783

M. B. Shymlock, Region IT
(404) 331-5596

Attachments:

1. Figure 1

2. GE SAL 303.0

3. List of Recently Issued NRC Information Notices