United States Nuclear Regulatory Commission - Protecting People and the Environment

GE Nuclear Energy

General Electric Company
175 Curtner Ave., San Jose, CA 95125

May 10, 2002
MFN 02-029

Document Control Desk
United States Nuclear Regulatory Commission
One White Flint North
11555 Rockville Pike
Rockviile, Maryland 20852-2738

Subject: Deviation in Barton Instruments Differential Pressure Indicating Switches

This letter provides information concerning a recently discovered deviation impacting Systems that use Barton Model 288A and 289A differential pressure indicating switches manufactured prior to 1986. These devices were manufactured by Barton Instrument Systems, LLC, and supplied to licensees by GE Nuclear Energy (GE-NE) as safety related components for both specified and un-specified applications. Barton issued a Nuclear Industry Advisory, dated March 4, 2002, revised March 14, 2002, to those plants that had purchased these devices directly from Barton, and also notified GE-NE. A number of the specified safety applications have been evaluated and GE-NE has determined that these are not reportable under 10 CFR Part 21.21. However, detailed information is not available on some specified safety applications, and GE-NE cannot evaluate the unspecified safety applications. Therefore, we have transferred information pursuant to 10 CFR Part 21.21(b) to those licensees known to be affected. Since additional licensees may have obtained these devices through other dedicating entities, we cannot assure ourselves that all end-users have been notified. We are therefore providing this information to the NRC for appropriate action.

The models identified were most likely assembled with an undersized washer in the switch plate locking mechanism for those instruments manufactured until the end of 1985. A 1/2" OD X 0.063" thick flat washer should have been used, while they might actually have been assembled with a 3/8" OD X 0.032" thick flat washer. The larger washer is more effective at preventing switch plate movement, as switch plate movement could result in instrument setpoint drift. There are no records to show that seismic qualification testing was performed with the undersized washer. Therefore, setpoint drift cannot be precluded as a result of a seismic or plant vibration events for instruments that are assembled with the undersized washer.

May 10, 2002
MFN 02-029

It is recommended that affected licensees inspect all Barton Model 288A and 289A differential pressure indicating switches manufactured prior to 1986 to determine if an undersized washer was used when the switch plates were assembled. If an undersized washer was used, the unit should be replaced or repaired. GE-NE recommends that the inspection be conducted at the next regularly scheduled maintenance or surveillance for the subject instrument. Licensees may choose to inspect, and repair or replace affected instruments in locations which are accessible and which are not in use during normal operation, prior to the next regularly scheduled maintenance or surveillance.

If you have any questions, please call me at (408) 925-5362.


Jason S. Post, Manager
Engineering Quality and Safety Evaluations

cc: S. D. Alexander (NRC-NRR/DISP/PSIB) Mail Stop 6 F2
G. C. Cwalina (NRC-NRR/DISP/PSIB) Mail Stop 6 F2
M. Larson (Barton Instrument Systems, LLC)
W. Cintron (Barton Instrument Systems, LLC)
T. S. Panetta (GE-NE)
J. F. Klapproth (GE-NE)
H. J. Neems (GE-NE)
PRC File (V. D. Schroer, GE-NE)


Page Last Reviewed/Updated Tuesday, June 30, 2020