Continued work on finding ground fault in 1A triplet magnets;
D. Preddy connected ohmeters to 1AQ14 & 15 power supplies with power leads disconnected. Ohmmeters were connected from magnet power leads to ground (pwr supply chassis).
- Q14 read 250 ohm and Q15 read 3 ohm.
- Disconnected power leads on Q14 and Q16 steering magnets. No change to ground faults.
Systematically moved wires off of magnets to find ground fault
- Moved north side asymmetric steering wire on live bus bars, no change
- Moved beam spill monitor (#57) cable, saw fluctuation in resistance on Q15.
- Moved disconnected thermocouple wire (from last year) on Q15, resistance change was observed.
- Moved thermocouple cable on coil #11, resistance change observed. No change on coil # 5.
- Resistance varied from 3 ohm to infinity.
Replaced RH bridge over Q15 shield block to facilitate re-installation of disconnected thermocouple.
- Removed RH bridge over Q15.
- Re-installed Q15 shield block.
- Re-installed 8' bridge over Q14 space.
- J. McKinnon reconnected thermocouple connectors & bound with Ø1/16" aluminum wire before covering. See photo.
Q14 re-covered with shielding.
- Cover plate on Q14 replaced.
- No water was found on beam line floor.
1AQ14 shielding restored and two lead panels replaced to cover T2 monument. See photo.
Tomorrow:
- Uncover Q15 # 16 to find ground fault.
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