Български
| Nuclear Facility: | Unit 6, Kozloduy NPP | ||||
| Date: | 30.10.2021 | Time: | 07:42 | ||
| Event title: Reactor scram of Unit 6 | |||||
| Event description: | |||||
| On 30.10.2021 Unit 6 operated at rated power. During the implementation of activities to reaching the minimum controllable reactor power level after annual outage and reloading, the automatic reactor scram has occurred. The reason for the scram was false signal for reducing “inlet-outlet” pressure difference of one of four main circulation pumps. Activities to identify the reason for the false signal have been performed. At 09:10 a leakage was found from a valve block of one of the three pressure sensors taking part in the reactor’s safety protection. As a result of this leakage the other two sensors were set on and as a result the reactor scram was triggered. At 02:10 after restoring the functionality of the valve block, the implementation of activities to reaching the minimum controllable reactor power level was continued. There has been no violation of the operational limits and conditions and respectively there have not been any changes in the radiological conditions. | |||||
| INES rating of the event: | Below Scale/Level 0 No safety significance | ||||
