Error message
Aggregator
The following cavities have been UnGSET 0: 2L11-7
The following cavities have been UnGSET 0:
2L11-7
Username: schoene
Date/Time: 06-04-26_11:58:16
RF Status: Good
Tuner Status: Good
Comment: UnGSET 0 - stepped on -100k - Swapped 50ohm res. and repaired HV Cable
Special Instructions:
Maintenance Tag: Component: 50 Ohm Resistor
HarpFitter: IHA0L03 - Degrader BS - MQL0L02 at -200G
The following cavity histories have been updated: Zone 1L05
The following cavity histories have been updated: 2L24-3
iocsoftIDXBS04 restoration failed
QuickPic - Software investigated ARC4A major alarm acknowledgement
ACC has been enabled in alarm handler
0L04 troubleshooting
unbypassed and recovered the 0L04-7 with ops's help. Not sure why it was tripping couple of days ago.
OPS started sending CW to ILD and 0L04 was trippy above 80 uA. Looking at the waveforms it was most likely cavity 3 tripping the zone.
This was the cavity I adjusted the GGXTA and GGBBC back in september. I compared the gradient and forward power from last september with what we have now and they are similar. Drive signal is higher than before which points to something in the drive path (chassis, preamplifier,klystron). Klystron cathode current looked similar.
"EESRF & I&C investigating iocnl1b comms (I&C to possibly contact software)"
COMMENT ON Investigate 20A MQK7S10, MQK6R09, MQK8A23
COMMENT ON Investigate 20A MQK7S10, MQK6R09, MQK8A23
HarpFitter: IHA0L03 - as found for Degrader BS
FSD Masking Tool: Successful System Masking for: BeamLossMonitor
Degrader setup - current limit setup
C Laser attenuator at 114 gives ~160nA CW on FC2, 204 gives 10uA (A3 + A4 + FC2)
5 minute run at 85 uA to ILD
Rf Expert was able to find that our issues were originating from 0L04-2/3. After working on them we were able to send 85 uA for 5 minutes with no trip. Interceptions looks good at 85 as well.
If the problems with 0L04 were coming from cavities 2 and 3, we will be able to increase the GSET in cavities 1 and 4, which will lower the energy locks.
The setup was saved on all save 27261. It is likely more can be done to increase the current, or the current could be pushed further, but we need to move on to degreader beam studies, so we will take what we have here for now.
High current High Energy injector check
High Energy Injector setup looks good. Ran beam up to 85uA CW to ILD (see figures attached). We had problem with IN04 cavities earlier tripping on high current. Final conclusion is that the source were cavities 2 and 3. Cavity 3 has amplifier problem. I refer you to RF experts for more details. We were able to run more than 5 minutes uninterrupted 85uA CW to ILD.
Everything else looks good to continue to NL. Degrader test starts now.
Save #27261










