A work request identified a local trouble alarm on the standby generator (standby
emergency diesel generator). Maintenance investigation of the trouble alarm was in progress when the control card for the standby generator failed (card controlled the frequency and voltage of the generator). Failure of this card disabled the generator from operating properly. The standby generator was declared
inoperable and production personnel immediately stopped production of licensed material that was supported by the standby generator. At 1800
CST the standby generator was repaired and tested. The standby generator is considered fully
operable at the time of this report. An investigation has been initiated to find why the control card failed. A 30 day reported will be released. NRC Region 2 (Jay Henson) was notified of this event by the licensee.