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Part 21 Report - 1999-340
| 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, August 27, 2026
Page Last Reviewed/Updated Thursday, August 27, 2026