United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for February 5, 2001

                       Headquarters Daily Report

                         FEBRUARY 05, 2001

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                    REPORT             NEGATIVE            NO INPUT
                    ATTACHED           INPUT RECEIVED      RECEIVED

HEADQUARTERS        X
REGION I                               X
REGION II                              X
REGION III          X
REGION IV                              X
PRIORITY ATTENTION REQUIRED  MORNING REPORT - HEADQUARTERS FEB. 05, 2001

Licensee/Facility:                     Notification:

                                       MR Number: H-01-0009
Abb Power                              Date: 02/05/01


Subject: Part 21 - Medium Voltage Circuit Breaker Failures Caused by
         Material Fatigue in Control Devices


Discussion:

ABB Power Distribution, a circuit breaker vendor, reported three breaker
failures documented at two nuclear power plants since December 1998. The
cause of these failures was fatigue of the metal at the base of the
spring retainer on the movable contacts, due to insufficient metal mass
at the base. In each failure, the broken spring retainer allowed the
spring to move out of its intended position, causing failure of the
control contacts to make and break properly.

The vendor states that the failures were observed at the Sequoyah and
Catawba nuclear power plants. The vendor notes that since the HK and
K-line type circuit breakers were first marketed in 1960, more than
22,000 such devices have been produced, and that each device had
5 movable contacts. The vendor also noted that from that population of
control devices, only these three failures have been reported.

The vendor states that for each movable contact, the spring retainer is
formed with a die by punching the contact from the opposite side of the
electrical contact mounting location. The height of the spring retainer,
therefore, determines the amount of material left at the base. The vendor
also states that in September, 1979, the spring retainer height was
lowered, so that control devices manufactured after that date have more
material at the base of the spring retainer than those manufactured
before that date.

Because movable contacts manufactured before September 1979, would have a
small possibility of this type of failure, the vendor recommends that
control devices purchased before 1981 be replaced with new control
devices on both HK and K-line breakers at the next scheduled breaker
maintenance. The vendor states that it will notify all customers who
purchased this product.

The NRC will post ensuing reports on this subject on its Web site at
http://www.nrc.gov/NRC/PUBLIC/PART21/2001.
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REGION III  MORNING REPORT     PAGE  2          FEBRUARY  5, 2001

Licensee/Facility:                     Notification:

Commonwealth Edison Co.                MR Number: 3-01-0003
Quad Cities 1 2                        Date: 02/03/01
Cordova,Illinois                       Phone Call from Licensee
Dockets: 50-254,50-265
BWR/GE-3,BWR/GE-3

Subject: QUAD CITIES EMPLOYEE FATALITY

Discussion:

On February 3, 2001, at 3:48 a.m. a family member discovered an
individual slumped over the wheel of his car in the Quad Cities Station
parking lot. Emergency medical technicians were called and the individual
was pronounced dead at the scene. Cause of death appears to be a heart
attack. The individual was employed at the Quad Cities Station as a
radiation protection technician. Only minor media interest in the form of
an obituary in the newspaper has been noted.

Regional Action:

The resident inspector was notified by the licensee.

Contact:  M. Ring                    (630)829-9703
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