Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555
March 3, 1989
Information Notice No. 89-23: ENVIRONMENTAL QUALIFICATION OF LITTON-VEAM
CIR SERIES ELECTRICAL CONNECTORS
Addressees:
All holders of operating licenses or construction permits for nuclear power
reactors.
Purpose:
This information notice is being provided to alert addressees to a potentially
generic safety problem involving CIR series electrical connectors manufactured
by the Veam Division of Litton Industries. These connectors have been
supplied to numerous commercial nuclear plants by Combustion Engineering, Inc.
(CE), and have been obtained by at least three plants through other channels.
It is expected that recipients will review the information for applicability
to their facilities and consider actions, as appropriate, to avoid similar
problems. However, suggestions contained in this information notice do not
constitute NRC requirements; therefore, no specific action or written response
is required.
Description of Circumstances:
Litton-Veam CIR series multi-pin electrical connectors are used in core exit
thermocouple (CET) and reactor vessel level monitoring (RVLM) systems supplied
to numerous plants by Combustion Engineering, Inc., and are used in other ap-
plications in at least three additional plants. A proprietary qualification
test report (CE NPSD-230-P) has been used to document environmental qualifi-
cation of the connectors for loss of coolant accident (LOCA) conditions in the
CE-supplied systems. During LOCA testing, the connector face seal gasket was
completely degraded and elastomeric inserts interacted with simulated contain-
ment spray solution which leaked into the connector. Insulation resistances
near 1,000 ohms were measured. CE has performed analyses to show that
resultant errors are acceptable in CE-supplied CET and RVLM system
thermocouple circuits. However, the moisture ingress and resultant low
insulation resistances are not acceptable for heater circuits in the RVLM.
For that application, CE developed two remedies; one is a clamp, and the other
is a new connector design. CE has advised that one of these remedies has been
used for all of the RVLM heater circuits. Unmodified CIR connectors are
believed to be still in use in other applications.
8902280104
. IN 89-23
March 3, 1989
Page 2 of 2
Details of this concern, including a list of plants believed to be affected,
are contained in NRC Inspection Report 99900401/88-01, dated January 10, 1989.
Discussion:
CE LOCA-tested the Litton-Veam connectors only in thermocouple circuits, which
tolerate relatively poor electrical characteristics. In other applications
such as transmitter and solenoid valve circuits, licensees are cau-tioned that
CE's testing (1) does not establish qualification and (2) strongly suggests
qualification problems. Connector failures could result in the loss of the
func-tions of connected qualified equipment.
No specific action or written response is required by this information notice.
If you have any questions about this matter, please contact the technical
contact listed below or the Regional Administrator of the appropriate regional
office.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contact: Richard C. Wilson, NRR
(301) 492-0997
Attachment: List of Recently Issued NRC Information Notices
. Attachment
IN 89-23
March 3, 1989
Page 1 of 1
LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
_____________________________________________________________________________
Information Date of
Notice No._____Subject_______________________Issuance_______Issued to________
89-22 Questionable Certification 3/3/89 All holders of OLs
of Fasteners or CPs for nuclear
power reactors.
89-21 Changes in Performance 2/27/89 All holders of OLs
Characteristics of Molded- or CPs for nuclear
Case Circuit Breakers power reactors.
88-73, Direction-Dependent Leak 2/27/89 All holders of OLs
Supplement 1 Characteristics of Contain- or CPs for nuclear
ment Purge Valves power reactors.
89-20 Weld Failures in a Pump 2/24/89 All holders of OLs
of Byron-Jackson Design or CPs for nuclear
power reactors.
89-19 Health Physics Network 2/23/89 All holders of OLs
or CPs for nuclear
power reactors, and
the following fuel
facilities:
Nuclear Fuel
Services of Erwin,
General Atomic, UNC
Montville, B&W LRC
Lynchburg, and B&W
Lynchburg.
89-18 Criminal Prosecution of 2/22/89 All holders of OLs
Wrongdoing Committed by or CPs for nuclear
Suppliers of Nuclear power reactors.
Products or Services
89-17 Contamination and Degra- 2/22/89 All holders of OLs
dation of Safety-Related or CPs for nuclear
Battery Cells power reactors.
89-16 Excessive Voltage Drop 2/16/89 All holders of OLs
in dc Systems or CPs for nuclear
power reactors.
__________________________________________________________________________________
OL = Operating License
CP = Construction Permit
..
