United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for July 7, 2006

Headquarters Daily Report

To top of page


Part 21 2006-0014-00 - Thermo Electron - Defective Paperless Data Acquisition Recorders


Sugar Land, Texas

License No:

MR Number: H-2006-0014
Date: 06/30/2006

Source Document: Fax



Part 21 2006-0014-00 - Thermo Electron - Defective Paperless Data Acquisition Recorders

The NRC was notified of the following Part 21 Report information via Event Notification EN 42678.

While performing preventative maintenance on a safety related Thermo Electron Controlled Smart View Color (CSVC) recorder, Brunswick identified that the recorder's rechargeable backup battery had separated. A similar failure had been found by Brunswick on a non-safety related recorder prior to this incident. Brunswick notified Thermo Electron on May 30, 2006.

Thermo Electron formed a team to evaluate the battery failures. The back-up battery installed on the CSVC is a NiCad sealed package. Thermo Electron determined that, as the batteries age, the potential exists whereby if the batteries are fully discharged (which could occur during an outage or a shut down condition), a reverse charging situation may occur when the recorders are brought back on-line. The byproduct is hydrogen gas, which can cause the battery to split open. Thermo Electron determined that this failure does not appear to create a hazardous condition within the recorder, and the recorder should continue to function properly while under power. However, should a recorder lose power after such a battery failure has occurred, the system configuration would be lost.

Corrective Action: Thermo Electron recommends that utilities with CSVC recorders that have been in service greater than three years, with original batteries installed, consider replacing the batteries at the next maintenance interval. The battery packs as originally installed on the CSVC are no longer available, but a replacement (Thermo Part Number 1063-0200-001, Revision A) has been identified, tested, and verified by Thermo Electron to be suitable for the backup battery application. Thermo Electron recommends a replacement cycle for the replacement battery pack of three years from the date the recorder is placed in service or the battery was replaced.

The NRC contacted the vendor via telephone and received the following list of plants affected by the Part 21: Shearon Harris, Brunswick, River Bend, Sequoyah, and Point Beach. Thermo Electron is in the process of notifying the affected sites.

Accession Numbers:

Accession No Accession Date
ML061860381 07/06/2006


Name Office Abbrev Phone No E-Mail
SIELLER, NICOLE S NRR (301) 415-3139 NSS@nrc.gov
Page Last Reviewed/Updated Thursday, March 29, 2012