INES-event
INES 0

MODERATOR DUMP TIME RECORDING HIGHER THAN NORMAL

The unit was shut down in a planned manner on 5.5.92 to attend to maintenance jobs in moderator system. While manually tripping the reactor, the time recorded in Recording Annunciator (RA) for the moderator level in calandria to drop from 91% full tank to 35% full tank was found to be 13.938 secs. against the normal value of 7.5 to 8 secs. Malfunctioning of the calandria level indicating instrument giving signal to RA on level reaching 35% full tank is suspected to be the cause of this event.
As the high dump time recorded is spurious, the event can be rated as level 0 under A-1R category of Table-1 of INES Users Manual.

Location: KALPAKKAM-1
Event date: Tue, 05-05-1992
Nuclear event report
Legenda & explanation