INES-event
INES 0

REACTOR TRIP DUE TO MALFUNCTION OF OPTICAL ISOLATOR

During the normal operation reactor was tripped due to the dropping of control rods. Investigation revealed that Control Element Assembly Calculator (CEAC) #1 was failed because one of the optical isolator was gone out. After replacing the wrong optical isolator the plant was returned to the operation on same day. There was no release of radioactive materials outside the reactor building and no unplanned exposure to employees.

Location: YONGGWANG-3
Event date: Mon, 07-08-1995
Nuclear event report
Legenda & explanation