Interlock Defeat

System(s) Affected:
Other / Misc

Interlock to be Defeated:
EGUN:BIAS and MPS FSD interlocks for BLM settings OK

Implementation:	Number:
Date: 2024-11-06 Time: 12:35:00	2024-505
Implemented By: Brandon Humphries
In Consultation With:

Status: Removed

Estimated Duration:
1 days

Reason for Defeat:
To allow for beam spill measurements for the new BLM fibres, more than one of the BLMs must be disabled to prevent tripping. So interlocks related to changing the BLM settings (including disabling) had to be defeated.

Number of Yellow Tags:
1

Location of Defeat Tag(s):
1- On cork board in back of DCR

1- On safety system box on E-LINAC side of the DCR

How Was Defeat Implemented?
Where is Defeat Located?:
Controls group member (Mike) implemented it in the Controls system. As per Mike: The calculation on the FSD's BLM_OK signal was changed to look at just the argon flow. The BLM Okay signal to the PLC was also changed to just look at argon flow. In both cases the BLM summaries are bypassed as a result.

Describe Alternate Protection:
Beam spill measurements will be done at low power (below 100W) and non-disabled BLMs will still trip from a beam loss normally. Tried disabling a BLM (EABT:LIC3B) while the EGUN:BIAS and beam were on, they did not trip. The EOECM will be used to ensure power remains below 100W.

Fault Reports:

Work Permits:

Disables:

Interlock Defeat

Removal:	Number:
Date: 2024-11-07 Time: 13:29:00	2024-505
Removed by: Brandon Humphries

Status: Removed

Interlock Verification Method:
Confirmed that EGUN:BIAS and FSD tripped when adjusting the setting of a BLM. See e-log entry https://web.accel.triumf.ca/elinac_elog/Elog_show_result.pl?inid=57085&style=thread&timemode=eventtime for pictures.

Number of Tags Removed:
2

Comments: