NDOS Commissioning Meeting 2011/05/19¶
Attendance: Jon, Gary, Susan, Zeb, Jan, Leon, Minerba, Mark Messier, Mark Mathis, Peter, Gavin, Denis, Mat, Ken
- NDOS Status and Channel Recovery Plans
- DAQ/Electronics Update & Plans
- DCS Update & Plans
- DataCheck Update
- AOB (All)
- uptime (run>30 minutes long and all 9 dcms in the readout) during the last week was ~70%
- active channel fraction (whole detector) dropped from ~78% to 65%. The following recent changes were observed in each DCM:
- dcm-3-04-02: ~90% --> ~56%
- dcm-3-04-01: ~97% --> ~80%
- dcm-3-03-01: ~97% --> ~85%
- dcm-3-02-03: ~72% --> ~42%
- dcm-3-02-02: ~70% --> ~42%
- dcm-3-02-01: ~85% --> ~73%
- dcm-3-01-03: ~90% --> ~85%
- dcm-3-01-02: ~95% --> ~91%
- dcm-3-01-01: ~87% --> ~80%
- Denis: some of the losses are due to cooling, where APDs are lost permanently after cooling
- Mat: humidity in the hall is high again (50%). Jon will contact Bill Moorehouse about this. Discussion about why electronics are sensitive to humidity. Leon would like to try to run a FEB in an environmental chamber, but it will take some time to develop the test.
- Mat: installed 15 cable-ectomized cables on side of di-block 2
- details are in doc-db 5980
- only 2/15 show an improvement; further study/thought is needed
- Denis: cooled DCM 4-2. Found a few FEBs had water lines swapped. Found a water leak (leaking on connection to heatsink), entire FEB was wet, so it was turned off.
DAQ/Electronics Update & Plans¶
- lots of stress testing (config. parameters set to value well beyond the nominal settings). Andrew N. has been leading the charge.
- corrupted data is now being seen, but it's not clear if it's due to the stress-testing. Bug was found and fixed in BNEVB; data corruption rate has decreased but not entirely.
- Mark suggests making raw data unpacking code more robust.
- Peter: could be version skew in Dispatcher.
- BNEVB was found to not to be able to handle high trigger rates, but this was expected and it is understood how to fix.
- dcm "names" have been changed to their logical names, not hardware names.
- Gennadiy made change to DDS that has improved stability of the messaging system.
DCS Update & Plans¶
- Leon: bug with DCM firmware that was causing it to lock when external<->internal command switch is made is being worked on.