Interlock Defeat

System(s) Affected:
Safety

Interlock to be Defeated:
BSM 55 defeated

Implementation:	Number:
Date: 2024-11-07 Time: 18:12:00	2024-506
Implemented By: Ryan Anderson
In Consultation With:

Status: Removed

Estimated Duration:
8 weeks

Reason for Defeat:
For BL1U production.

Number of Yellow Tags:
2

Location of Defeat Tag(s):
Back of rack A in DCR

DCR defeat board

How Was Defeat Implemented?
Where is Defeat Located?:
Rack A BSM 55 pinned. BSM 55 working level set to 101 to stop audible alarms.

Describe Alternate Protection:
UCN BSMs plotted in DCR, watching during kicking. Approved by RSO by email Nov 7, 2024, until end of calendar year 2024.

Fault Reports:

Work Permits:

Disables:

Interlock Defeat

Removal:	Number:
Date: 2024-11-12 Time: 00:30:00	2024-506
Removed by: Eric Chapman

Status: Removed

Interlock Verification Method:
BSM #55 set to nominal operating level of 25. UCN not operating until next week.

Number of Tags Removed:
2

Comments:

Eric Chapman: 2024-11-12 00:36:23.252045
UCN spills can be significantly reduced by lowering the ISIS pulser. It is not best practice to operate with a defeat in place that is not required. Setting a BSM to '101' should only be done when absolutely required, particularly BSM 55 as it is a valuable tuning tool.