sheila.dwyer@LIGO.ORG - posted 01:02, Friday 03 April 2015 - last comment - 10:22, Friday 03 April 2015(17651)
HAM3 seismic problem
Evan, Sheila, Koji
We ran into some difficulty tonight with HAM3 seismic, both HEPI and the ISI are tripping. We've tried several things:
- disabled ISC outputs, the IMC-MCL output, and the isc inputs to MC2. There were no signals going to PR2.
- turned off all ISI sensor correction by setting gains to 0 in the MATCH filter banks
- The HPI sensor correction was off already
- things still tripped, so we switched the GS13s to low gain mode.
- It seems that if we leave HEPI tripped and isolate the ISI, it stays isolated without tripping, so HEPI must be the problem. We looked at the pump servo screen but nothing seems obviously wrong....
Images attached to this report
Comments related to this report
It's a bad ADC. Richard is working on replacing it right now.
J. Kissel, J. Warner, R. McCarthy Update: H3 IPS sensor died last night around 7:30 UTC (see attached screenshot). We went out to the pier, no obvious cable problems. We manually moved the HEPI pier, and saw all Horz. sensors register motion *except* H3. We swapped H3 and V3 cables, and the H3 sensor readout by the V3 channel registers the motion. So, we assume problems are upstream of the sensor in the pier pod / satellite box or further up. Richard and Jim continue to investigate. Stay tuned!
Images attached to this comment
