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Unit 1 was performing a planned refueling … Unit 1 was performing a planned refueling outage surveillance test, FNP-1-STP-40.0, 'Safety Injection with Loss of Off-Site Power (LOSP).' The systems were being returned to normal following the actuation portion of the test. When the B1F Sequencer Test Trip Override Switch was taken to the 'ON' position, the 1-2A Diesel Generator output breaker opened, which caused a loss of power to the 'A' Train 4 kV busses. Prior to the event, the 1-2A Diesel Generator was running at normal speed and voltage carrying the 'A' Train 4kV busses. When the diesel generator output breaker opened, it then reclosed upon receipt of the LOSP signal causing the LOSP sequencer loads to automatically start. This included the 1C Component Cooling Water Pump, the 1A High Head Safety Injection Pump (discharge isolation was closed prior to the event), and the 1A and 1B SW pumps. Therefore, during the test, the system actuated in a way that was not part of the planned surveillance testing. The 1A RHR pump was in shutdown cooling mode at the time of the event and was load shed. RHR was restarted manually by the operating crew approximately 1 minute later (no auto start (signal) present due to a loss of site power - LOSP signal without a safety injection signal present).</br>The investigation revealed that a step in the procedure sequence was not performed during the restoration portion of the test. The operator did not parallel the diesel with off-site power prior to operating the B1F Sequencer Test Trip Override Switch which opened the diesel output breaker without off-site power aligned to the 'A' Train 4kV busses. The 1-2A Diesel Generator was subsequently paralleled to the grid and properly shutdown per the test procedure restoration.</br>The licensee notified the NRC Resident Inspector.ensee notified the NRC Resident Inspector. +
17:20:00, 5 April 2012 +
47,809 +
18:21:00, 5 April 2012 +
17:20:00, 5 April 2012 +
Unit 1 was performing a planned refueling … Unit 1 was performing a planned refueling outage surveillance test, FNP-1-STP-40.0, 'Safety Injection with Loss of Off-Site Power (LOSP).' The systems were being returned to normal following the actuation portion of the test. When the B1F Sequencer Test Trip Override Switch was taken to the 'ON' position, the 1-2A Diesel Generator output breaker opened, which caused a loss of power to the 'A' Train 4 kV busses. Prior to the event, the 1-2A Diesel Generator was running at normal speed and voltage carrying the 'A' Train 4kV busses. When the diesel generator output breaker opened, it then reclosed upon receipt of the LOSP signal causing the LOSP sequencer loads to automatically start. This included the 1C Component Cooling Water Pump, the 1A High Head Safety Injection Pump (discharge isolation was closed prior to the event), and the 1A and 1B SW pumps. Therefore, during the test, the system actuated in a way that was not part of the planned surveillance testing. The 1A RHR pump was in shutdown cooling mode at the time of the event and was load shed. RHR was restarted manually by the operating crew approximately 1 minute later (no auto start (signal) present due to a loss of site power - LOSP signal without a safety injection signal present).</br>The investigation revealed that a step in the procedure sequence was not performed during the restoration portion of the test. The operator did not parallel the diesel with off-site power prior to operating the B1F Sequencer Test Trip Override Switch which opened the diesel output breaker without off-site power aligned to the 'A' Train 4kV busses. The 1-2A Diesel Generator was subsequently paralleled to the grid and properly shutdown per the test procedure restoration.</br>The licensee notified the NRC Resident Inspector.ensee notified the NRC Resident Inspector. +
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00:00:00, 5 April 2012 +
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