UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555
December 15, 1989
Information Notice No. 89-45, SUPPLEMENT 2: METALCLAD, LOW-VOLTAGE
POWER CIRCUIT BREAKERS
REFURBISHED WITH
SUBSTANDARD PARTS
Addressees:
All holders of operating licenses or construction permits for nuclear power
reactors.
Purpose:
This information notice supplement is being provided to alert addressees to
the problem of potentially defective General Electric (GE) and Westinghouse
(W) metalclad, low-voltage power circuit breakers and associated equipment
supplied to nuclear power plants by the Satin American Corporation (SA) and
its affiliate, Circuit Breaker Systems, Incorporated, both of Shelton,
Connecticut, or by any of SA's representatives. Of particular concern are
GE EC-type, electromechanical, overcurrent trip devices, in safety-related
applications, or available for use in such applications, supplied by these
organizations.
It is expected that recipients will review this information for
applicability to their facilities and consider actions, if appropriate, to
avoid similar problems. However, suggestions contained in this notice do
not constitute NRC requirements; therefore, no specific action or written
response is required.
Description of Circumstances:
NRC Information Notice (IN) No. 89-45 discussed a General Electric (GE) type
AKF-2-25 metalclad, low-voltage power circuit breaker (field discharge
configuration) supplied to the Quad Cities nuclear power plant by SA that
was found to have been built or refurbished with nonstandard and substandard
parts.
Supplement 1 to IN 89-45 discussed the NRC's findings on GE EC-type trip
devices from follow-up inspections at utilities that had procured circuit
breakers and related electrical equipment such as trip devices from SA. As
discussed in detail in the supplement, the NRC found EC-type trip devices
supplied by SA that were refurbished with nonstandard and possibly
substandard parts, or old, used parts, in nonstandard combinations using
questionable fabrication methods. Some of these devices had failed in
service or testing.
Additional tests were conducted by utility personnel and were observed by
representatives of the original manufacturer and the NRC. In these tests,
the devices
8912110177
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IN 89-45, Supplement 2
December 15, 1989
Page 2 of 3
exhibited inconsistent performance including some test failures.
Subsequently, the NRC obtained more of these SA-supplied trip units and had
them tested and examined at the GE Apparatus Service Facility in Atlanta,
Georgia. This facility is currently the sole original equipment
manufacturer of EC-type trip devices. The results of this testing were also
unsatisfactory, with virtually all the devices tested exhibiting
out-of-specification operation of one or more of their functions in some
portion of their design operating ranges. The devices were not adjustable
such that they would operate within tolerance at all points within their
nameplate-identified characteristic curves, and some of them failed to
perform one or more of their trip functions entirely. Post-testing
examination of these devices confirmed that they were rebuilt with used
parts, in incorrect combinations. Some of the parts were so degraded with
age that they were no longer suitable for use, and some of the
unsatisfactory test results were directly attributable to the discrepancies
in the conditions found. Some of the fabrication methods used could
contribute to erratic operation and failure. Such latent defects would not
be readily detectable during routine inspection and testing and could render
the affected circuit breakers unreliable during normal operation due to
spurious tripping and lack of overcurrent protection.
The SA facility in Shelton, Connecticut, suffered major damage in a fire in
July 1989. The resultant destruction of records may make it difficult or
impossible for SA's customers to audit the company and obtain the
information necessary to assure that previously purchased equipment was in
full compliance with the applicable specifications and purchase order
requirements.
In order to assess the scope of the problem with regard to GE EC-type trip
devices, all nuclear utilities were contacted by the Nuclear Management and
Resources Council (NUMARC) at the request of the NRC to determine which
utilities had purchased low-voltage electrical switchgear or related
equipment from SA that was used or available for use in safety-related
applications. Information thus obtained indicated that about 40 utilities
had purchased equipment of the types in question in the last 5 or 6 years,
much of which was purchased as commercial grade equipment and was used in or
available for use in nonsafety-related applications only. Of the NUMARC
respondents, several utilities initially reported that they had GE AK-type
circuit breakers containing EC-type over-current trip devices supplied by SA
which were possibly used in safety-related applications. These utilities
subsequently contacted the NRC.
All licensees thus far identified that have GE EC-type trip devices
installed in safety-related circuit breakers have committed to acceptable
courses of action to replace the suspect trip devices or to consult with GE
in reviewing and determining the suitability of the trip devices for
continued use.
As a result of the NRC's continuing inspections of the types of equipment in
question at licensed facilities, the NRC has identified additional
SA-supplied equipment that may be defective. NRC inspections of SA-supplied
Westinghouse low-voltage switchgear at several plants, including type DB-25
and DS-416 circuit breakers at the Cooper Nuclear Station and the Zion
Nuclear Power Station respectively, have identified apparent irregularities
when compared to the original equipment. Specifically, apparent differences
in pole shaft and spring-pin configuration, wiring type, frame finish, and
nameplates were observed..
IN 89-45, Supplement 2
December 15, 1989
Page 3 of 3
It is possible, therefore, that this and other equipment supplied by SA may
not be suitable for service without additional operability reviews in
consultation with the original equipment manufacturer.
The NRC is interested in obtaining information on circuit breakers and
related pieces of equipment that have been found with deficiencies such as
those described in IN 89-45, Supplement 1 thereto, and this supplement.
Documentation, in as much detail as practicable, of any such deficiencies
noted, especially in recent procurements and in cases of possible improper
servicing or refurbishment, is important. Licensees may communicate
information of this type by telephone to the technical contacts listed
belw.
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 NRR project
manager.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contacts: S. D. Alexander, NRR
(301) 492-0995
U. Potapovs, NRR
(301) 492-0984
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