Information Notice 1994-41, Problems with General Electric Type CR124 Overload Relay Ambient Compensation
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C.
20555
June 7, 1994
PROBLEMS WITH GENERAL ELECTRIC TYPE CR124
OVERLOAD RELAY AMBIENT COMPENSATION
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 potential for out-of-tolerance ambient
compensation in certain configurations of General Electric (GE) Type CR124 overload relays. It is expected that recipients will review the information
for applicability to their facilities and consider actions, as appropriate, to
avoid similai'--problems.
However, suggestions contained in this information
notice are not NRC requirements; therefore, no specific action or written
response is required.
Description of Circumstances
After some field test failures, in which several Type CR124 overload relays
exhibited out-of-tolerance trip times, the relays were returned to the
manufacturer, GE Electrical Distribution and Control (ED&C).
GE ED&C
discovered that on relay models CR124K028, K128, L028, and L128, manufactured
before October 1990, many of the ambient temperature-compensating bimetal
elements (sometimes called ambient compensating springs) had been installed
upside down because of a problem with the marking of the elements.
In this
condition, the incorrectly installed element can adversely affect the trip
timing of the relay. These overload relays are typically used in conjunction
with starters or motor controllers, many of which may serve safety-related
loads. In April 1991, GE Nuclear Energy (GE NE) issued a "Germane to Safety"
letter to all boiling water reactor customers and certain other customers
concerning the relays. However, the NRC has learned that other licensees may
also be affected.
Discussion
The ambient temperature compensating bimetal element or spring is intended to
adjust the trip forces inside the relay so that the trip time as a function of
overload current is consistent with the design characteristic curves over a
wide range of ambient temperatures. According to GE, the improperly installed
ambient compensating bimetals will permit the overload relays to work
correctly within a temperature range of 15-200C [59-68*F].
However, at lower
temperatures, i.e., 0-15'C [32-59°F], the ambient compensation would cause
9406010125 PC
tE
No '("C- e CT q -ot
q
L
slot
sha
'M
A
IN 94-41 June 7, 1994 trip times above published specifications (time-current curves). At higher
temperatures, i.e., 20-40'C [68-1040F], which is more typical of nuclear plant
installations, the ambient compensations would cause trip times below
published specifications.
GE ED&C did not have data on the magnitude of
deviations from the published time-current curves.
GE NE indicated that the above identified models made before October 1990 may
be affected by this problem.
To identify when the relays were built, they are
marked with date codes consisting of two letters.
The first letter, "N"
through "Z" (skipping IQ"), indicates month of manufacture. The second letter
indicates the year with "D" meaning 1989, NER meaning 1990, etc. Hence relays
of the affected models built before October 1990, i.e., in September 1990 and
earlier (date codes "WE" and earlier), are affected.
ED&C has issued no
service advice letters (SALs), nor has GE NE issued any service information
letters (SILs), on this issue. Since late 1991, ED&C has used 5-character, alphanumeric, in lieu of 2-letter date codes for the relays and similar
components.
Because the affected relays are reported to work properly within the
temperature range of 15-20*C [59-68*F], ED&C recommended evaluating individual
applications in terms of actual service conditions and performance
requirements to determine the potential impact on operability of the overload
relays with defective ambient compensation. In addition, because some of the
potentially affected relays may not be defective, GE ED&C provided a test
procedure that may be used as an alternative to wholesale replacement to
identify those relays that actually have the improperly installed ambient
compensation bimetal. The procedure is to test the relays at a nominal
overload current (e.g., 300 percent) at room temperature (e.g., 25°C [770F])
and then repeating the test after thermal soaking at 40*C [104°F] and
verifying that the cool and warm trip times at the same overload level are
within 10 percent of each other.
If these relays fail this test and the
condition cannot be tolerated because of requirements of the application, ED&C
stated that these relays would need to be replaced because they cannot be
repaired. ED&C also recommended the test procedure described above for
general use on ambient compensated thermal overload relays, installed or in
storage, which ED&C recommended testing at least every five years.
IN 94-41 June 7, 1994 This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact
the technical contact listed below or the appropriate Office
Nuclear
Reactor Regulation (NRR) project manager.
Bran K. Grimes, Director
Division of Operating Reactor Support
Office of Nuclear Reactor Regulation
Technical contact:
Stephen D. Alexander, NRR
(301) 504-2995 Attachment:
List of Recently Issued NRC Information Notices
A tachment 1
June 7, 1994 LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
Information
Date of
Notice No.
Subject
Issuance
Issued to
94-40
94-39
94-38
94-37
94-36
91-81, Supp. 1
94-35
Failure of a Rod Control
Cluster Assembly to Fully
Insert Following a Reactor
Trip at Braidwood Unit 2
Identified Problems in
Gamma Stereotactic
Radiosurgery
Results of a Special NRC
Inspection at Dresden
Nuclear Power Station
Unit 1 Following a Rupture
of Service Water Inside
Containment
Misadministration Caused
by a Bent Interstitial
Needle during Brachy- therapy Procedure
Undetected Accumulation
of Gas in Reactor
Coolant System
Switchyard Problems that
Contribute to Loss of
Offsite Power
NIOSH Respirator User
Notices, "Inadvertent
Separation of the Mask- Mounted Regulator (MMR)
from the Facepiece on the
Mine Safety Appliances (MSA)
Company MMR Self-Contained
Breathing Apparatus (SCBA)
and Status Update"
05/26/94
05/31/94
05/27/94
05/27/94
05/24/94
05/19/94
05/16/94
All holders of OLs or CPs
for pressurized-water
reactors (PWRs).
All U.S. Nuclear Regulatory
Commission Teletherapy
Medical Licensees.
All holders of OLs or CPs
for NPRs and all fuel cycle
and materials licensees
authorized to possess spent
fuel.
All U.S. Nuclear Regulatory
Commission Medical Licensees
authorized to use brachy- therapy sources in high-,
medium-, and pulsed-dose- rate remote afterloaders.
All holders of OLs or CPs
for nuclear power reactors.
All holders of OLs or CPs
for nuclear power reactors.
All holders of OLs or CPs
for nuclear power reactors, and all licensed fuel
facilities.
OL = Operating License
CP = Construction Permit
IN 94-41 June 7, 1994 This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact
the technical contact listed below or the appropriate Office of Nuclear
Reactor Regulation (NRR) project manager.
oWginalsigned DI
Brian IL 1rneS
Brian K. Grimes, Director
Division of Operating Reactor Support
Office of Nuclear Reactor Regulation
Technical contact:
Stephen D. Alexander, NRR
(301) 504-2995 Attachment:
List of Recently Issued NRC Information Notices
- See previous concurrence.
OFFICE
VIB/DRIL
SC/VIB/DRIL
TECH ED
BC/VIB/DRIL
D/DRIL
NAME
SAlexander*
GCwalina*
RSanders*
LNorrholm*
CERossi*
DATE
1
01/07/94
01/13/94
02/02/94
01/24/94 Ad
I'
01/31/94 OFFICE
EELB/DE
OGCB/DORS
I
ABC/OGCB/DORS
D /M< N
D
.
AE
0
9
0
-20
NAME
CBerlinger*
PWen*
AKug
ler
- {/
DATE
02/22/94
03/08/94
03/16/94
06/1 /94 DOCUMENT NAME: 94-41.IN
IN 94-XX
March xx, 1994 This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact
the technical contact listed below or the appropriate Office of Nuclear
Reactor Regulation (NRR) project manager.
Brian K. Grimes, Director
Division of Operating Reactor Support
Office of Nuclear Reactor Regulation
Technical contact:
Stephen D. Alexander, NRR
(301) 504-2995 Attachment:
List of Recently Issued NRC Information Notices
- See previous concurrence.
OFFICE I VIB/DRIL
SC/VIB/DRIL
TECH ED
BC/VIB/DRIL
D/DRIL
NAME
SAlexander*
GCwalina*
RSanders*
LNorrholm*
CERossi*
DATE
01/07/94
01/13/94
02/02/94
01/24/94
01/31/94 OFFICE
EELB/DE
OGCB/DORS
ABC/OGCB/DORS
D/DORS/NRR
NAME
CBerlinger*
PWen*
AKugler
B_
__KGrimes
DATE
02/22/94
03/
/94
03/08/94
03/1K/9403/ /94 DOCUMENT NAME:
CR124AC.PCW
,tJt 1e)
V
.-'
IN 94-XX
March xx, 1994 No specific action or written response is required by this information notice.
If you have any questions regarding this matter, please contact the technical
contact listed below or the appropriate Office of Nuclear Reactor Regulation
(NRR) project manager.
Brian K. Grimes, Director
Division of Operating Reactor Support
Office of Nuclear Reactor Regulation
Technical contact:
Stephen D. Alexander, NRR
(301) 504-2995 Attachment:
List of Recently Issued NRC Information Notices
- See previous concurrence.
OFFICE
VIB/DRIL
SC/VIB/DRIL
TECH ED
BC/VIB/DRIL
D/DRIL
NAME
SAlexander*
GCwalina*
RSanders*
LNorrholm*
CERossi*
DATE
01/07/94 j01/13/94 J02/02/94
101/24/94
101/31/94 OFFICE
EELB/DE
OGCB/DORS
ABC/OGCB/DORS
D/DORS/NRR
NAME
CBerlinger*
PWen
T
IC__
AKugler
BKGrimes
DATE
02/22/94
03___94
__03/
/94
03/
/94
103/ /94 OCUMENT N AME: CR124AC.PCW
1-.%
IN 94-XX
February XX, 1994 GE NE stated that annf the affected models made before October 1990 should
be considered suspect a should be replaced. To identify when the relays
were built, they are markel with date codes consisting of two letters. The
first letter, "NO through "
" (skipping "Qu), indicates month of manufacture.
The second letter indicates t year with "E"
meaning 1990, OF" meaning 1991, etc. Hence relays of the affec d models stated above built before October
1990, i.e., in September 1990 an earlier (date codes "WE" and earlier), are
affected.
ED&C reportedly correct
the problem on these models in September
1990 so that date codes for October
90 and later, i.e., "XE" (October 1990),
"YE" (November 1990), "ZE" (December
90), INF" (January 1991), etc., should
not be affected. ED&C has issued no se ice advice letters (SALs), nor has GE
NE issued any service information letters (SILs) on this issue.
GE NE also reported that ED&C recommend , in addition to replacing suspect
relays, testing thermal overload relays that re installed and in storage at
least every 5 years. ED&C's procedure is to
st the relays at a nominal
overload current (e.g., 300 percent) at room teperature (e.g., 25OC/77'F) and
also after thermal soaking at 40*C/104OF and ver ying that the cool and warm
trip times at the same overload level are within 1 percent of each other. If
not, ED&C recommended replacing the relays because
ey cannot be repaired.
No specific action or written response is require by this information
notice. If you have any questions regarding this matt r, please contact one
of the technical contacts listed below or the appropria
Office of Nuclear
Reactor Regulation (NRR) project manager.
Brian K. Grimes, Directo
Division of Operating Rea tor Support
Office of Nuclear Reactor Regulation
Technical contacts:
Stephen D. Alexander, NRR (301) 504-2995 Attachments: 1. List of Recently Issued NRC Information Notices
- See previous concurrence.
OFFICE
VIB/DRIL
SC/VIB/DRIL
TECHED
BC/VIB/DRIL
D/DRIL
NAME
SAlexander*
GCwalina*
RSanders*
LNorrholm*
CERossi*
DATE
01/07/94
01/13/94
02/02/94
01/24/94
01/31/94 COPY
YES
YES
NO
NO
NO
OFFICE
EELB______i__e__OGCB/DORS
BC/OGCB/DORS
D/DORS/NRR
NAME
CBerlfnger
-Rliies4 BKGrimes
DATE
02/22/94
02/ /94
02/ /94
02/ /94
02/ /94 COPY
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
OFFICIAL RECORD COPY
DOCUMENT NAME: CR124AC.IN
IN 94-XX
January XX, 1994 GE NE stated t t any of the affected models made before October 1990 should
be considered susp t and should be replaced. To identify when the relays
were built, they are arked with date codes consisting of two letters. The
first letter, "N" thro h HZ" (skipping "Q"), indicates month of manufacture.
The second letter indic es the year with "E"
meaning 1990, "F" meaning 1991, etc. Hence relays of the ffected models stated above built before October
1990, i.e., in September 1 %0 and earlier (date codes "WE" and earlier), are
affected. ED&C reportedly c rrected the problem on these models in September
1990 so that date codes for Octqber 1990 and later, i.e., "XE" (October 1990),
"YE" (November 1990), "ZE" (Decei
er 1990), "NF" (January 1991),
etc., should
not be affected.
ED&C has issued b Service Advice Letters (SALs), nor has GE
NE issued any Service Information Le ters (SILs) on this issue.
GE NE reported also that ED&C recome nded, in addition to replacing suspect
relays, testing thermal overload relays
at are installed and in storage at
least every 5 years.
ED&C's procedure is o test the relays at a nominal
overload current (e.g., 300 percent) at roo temperature (e.g., 25OC/770F) and
also after thermal soaking at 40*C/104*F and erifying that the cool and warm
trip times at the same overload level are with
10 percent of each other. If
not, ED&C recommended replacement because these elays cannot be repaired.
No specific action or written response is requ ed by this information
notice. If you have any questions regarding this aitter, please contact one
of the technical contacts listed below or the approptate Office of Nuclear
Reactor Regulation (NRR) project manager.
Brian K. Grimes, Director
Division of Operating Reactor Support
Office of Nuclear Reactor Regulation
Technical contacts: Stephen D. Alexander, NRR (301) 504-2995 Attachments: 1. List of Recently Issued NRC Information Notices
- See previous concurrence.
-
- -
l
OFFICE
VIB/DRIL
SC/VIB/DRIL
TECHED
BC/VIB/DRIL
DDRI
NAME
SAlexander*
GCwalina*
yiua.,k14 LNorrholm*
CERossi*
DATE
01/07/94
01/13/94
02/ V&/94
01/24/94
01/31/94 COPY
YES
YES
NO
NO
NO
OFFICE
EELB/DE
OGCB/DORS
BC/OGCB/DORS
D/DORS/NRR
NAME
CBerlinger
RKiesel
BKGrimes
DATE
01/ /94
01/ /94
01/ /94
01/
/94
01/
/94 COPY
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
a_&_hf
9 Al
UNI4lA AP
OFFICIAL RECORD COPY
UULUMtNI
N
Li
X1~t;
IN 94-XX
January XX, 1994 GE NE stated that any of the a fected models made before October 1990 should
be considered suspect and should e replaced. To identify when the relays
were built, they are marked with ate codes consisting of two letters.
The
first letter, IN' through "Z" (ski ping "Q"), indicates month of manufacture.
The second letter indicates the yea with "E" meaning 1990, "F" meaning 1991, etc.
Hence relays of the affected m dels stated above built before October
1990, i.e., in September 1990 and ear ier (date codes "WE" and earlier), are
affected.
ED&C reportedly corrected t
problem on these models in September
1990 so that date codes for October 199 and later, i.e., "XE" (October 1990),
"YE" (November 1990), "ZE" (December 199 I, INFO (January 1991), etc., should
not be affected.
ED&C has issued no Servi e Advice Letters (SALs), nor has GE
NE issued any Service Information Letters ( ILs) on this issue.
GE NE reported also that ED&C recommended in addition to replacing suspect
relays, testing thermal overload relays that re installed and in storage at
least every 5 years.
ED&C's procedure is to t st the relays at a nominal
overload current (e.g., 300 percent) at room te perature (e.g., 25OC/770F) and
also after thermal soaking at 40OC/104OF and ve *fying that the cool and warm
trip times at the same overload level are within 10 percent of each other.
If
not, ED&C recommended replacement because these r lays cannot be repaired.
No specific action or written response is requ red by this information
notice.
If you have any questions regarding this atter, please contact one
of the technical contacts listed below or the appr
iate Office of Nuclear
Reactor Regulation (NRR) project manager.
Brian K. Grimes, Director
Division of Operating Reactor Support
Office of Nuclear Reactor Regulation
Technical contacts:
Stephen D. Alexander, NRR (301) 504-2995 Attachments: 1. List of Recently Issued NRC Information Notices
OFFICE
VIB/DRIL
SC/ VW RIL
TECHED
BC/ I /DRIL
D/DRIL
NAME
SAlexand
GC_
Wi
DATE
01/c1/94
0l13 94
01/ /94
01
94 COPY
Y
YE
NO
NO
YES
YNOYES NO
OFFICE
EELB/DE
OGCB/DORS
BC/OGCB/DORS
D/DORS/NRR
NAME
CBerlinger
RKiesel
BKGrimes
DATE
01/ /94
01/ /94
01/ /94
01/ /94
01/ /94 COPY
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
ncr~rTIAI
nrrnnnr, rrl.hraI-
AK
,.I
,^AM
T&I
Urr LUlRL ICUKU bUM
UUUUMtNI
NMMt:
LK1z4qA%.1N