Interlock Defeat

System(s) Affected:
Diagnostics

Interlock to be Defeated:
E-LINAC BLM "Argon Flow OK" interlocks bypassed

Implementation:	Number:
Date: 2024-09-18 Time: 06:51:00	2024-461
Implemented By: Brandon Humphries
In Consultation With:

Status: Removed

Estimated Duration:
2 weeks

Reason for Defeat:
BLM argon flow #1 (EHAR:FG01:RDFLOW) and flow #2 (EHAR:FG02:RDFLOW) are showing faulty readings, which cause the EGUN:BIAS to trip (via "BLM Stat OK" interlock). To prevent these trips, the "Argon Flow OK" interlock for the BLM system was defeated (which feeds into the BLM Stat OK interlock).

Number of Yellow Tags:
2

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 implemented the bypass directly in ELMPS01IOC under WP#A2024-09-17-4.

Describe Alternate Protection:
Alternate protection is provided by the Argon pressure reading (EHAR:PG01:RDPRESS) and that currently we are only able to run beam in the low energy section (Argon is only needed for LICs, which don't start until the medium energy section) while waiting for the cryogenics system to be cooled down. Verified that the EGUN:BIAS "BLM Stat Ok" interlock still works by adjusting the settings of one BLM (see e-log entry https://web.accel.triumf.ca/elinac_elog/Elog_show_result.pl?inid=56233&style=entry&timemode=eventtime). Also verified that the "Argon Flow OK" indicator is green although both Flow #1 and Flow #2 are reading 0 ccm (defeat is working).

Fault Reports:
17298

Work Permits:
A2024-09-17-4

Disables:

Interlock Defeat

Removal:	Number:
Date: 2024-10-01 Time: 13:04:00	2024-461
Removed by: Brandon Humphries

Status: Removed

Interlock Verification Method:
Manually turned down supply flow of Argon until it hit the interlock limit. Confirmed expected result. See e-log for details: https://web.accel.triumf.ca/elinac_elog/Elog_show_result.pl?inid=56384&style=thread&timemode=eventtime

Number of Tags Removed:
2

Comments: