United States Nuclear Regulatory Commission - Protecting People and the Environment

LICENSEE: ABB COMBUSTION ENGINEERING
SITE: ABB COMBUSTION ENGINEERING EN NUMBER: 35879
DOCKET: EVENT DATE: 06-29-99
RX TYPE: EVENT TIME:
VENDORS: NOTIFY DATE: 06-29-99
EMERGENCY CLASS: N/A REGION: 1 STATE: CT TIME: 16:28
OPS OFFICER: BOB STRANSKY
10 CFR SECTION: CCCC UNSPECIFIED PARAGRAPH
10 CFR PART 21 REPORT DUE TO DEFECTIVE OSCILLATION POWER RANGE MONITORS

The following text has been excerpted from a letter submitted via facsimile from the vendor:

"The defect concerns the ABB Oscillation Power Range Monitor (OPRM) delivered to Susquehanna 1 & 2, Clinton, Hope Creek, WNP-2, Perry, LaSalle 1 & 2, Dresden 2 & 3 and Quad Cities 1 & 2. Specifically, the defect concerns the Slave OPRM module randomly resetting, potentially causing the OPRM trip channel to be out of service for a short period of time, typically under one minute. The defect could lead to non-conservative failure of detecting and suppressing thermo-hydraulic core oscillations during this time.

"None of the OPRM systems are presently being used to detect and suppress core oscillations. Installed OPRM systems are in the monitor mode with the trip contacts disabled."

Page Last Reviewed/Updated Thursday, March 29, 2012