During monthly equipment swapping on October 26, 2012, the licensee attempted to secure the S-2B-SB from the main control board. The fan stopped when the switch was turned to the OFF position, but automatically restarted when the switch was released without a valid start signal. The inspectors identified that the failure of the S-2B-SB to remain stopped when secured from the main control board adversely affected compliance with TS
Surveillance Requirements (SR) 4.8.1.1.2 F.4 which verifies operability of the B
EDG, B Electrical bus and B sequencer. Additional inspection activities are needed to determine the extent of condition, relative to SR compliance, and if a performance deficiency exists. Pending the results of this additional inspection, an
URI will be opened and designated as
URI 05000400/2012005- 01, Failure of the Primary Shield Supply Fan (S-2B-SB) to Remain Secure when Stopped.