Computer-Controlled Refueling Machine at Fort St. Vrain

The refueling system for the Fort St. Vrain Nuclear Generating Station uses a small digital computer for automatic control to handle approximately 3000 fuel and reflector blocks which constitute the reactor core. The computer has complete control of the handling mechanism, which has four freedoms of motion, and also logs information concerning all fuel movements for inventory purposes. Since safety is a prime consideration in equipment associated with a nuclear power plant, a combination of hardware and software protection monitors provides for fail-safe operation. Operating experience has proved that automatic control of the fuel handling process is approximately five times faster than manual operation with the same machine. In addition, operator errors are eliminated and an accurate log of all fuel movements is recorded.