Table 1: Main sequence of events [11].

EventTime (hh:mm:ss)

Loss of offsite load10:27
Turbine overspeed protection started (closure of turbine governor valves with steam dump valve opening)10:27:0
Alarm ROD BANK LO-LO LIMIT10:28:18
Safety injection signal10:29:02
“Unusual event” was declared10:55
Diesel generator number 1 (2) stopped11:20 (11:34)
Reactor coolant pump number 1 restarted11:55
Plant transited to a “hot standby” mode, the termination of “unusual event” was declared12:15

from measured data; LO: low; LO-LO is also called LO-2.