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Entry  Mon Apr 8 11:53:17 2019, gautam, Update, CDS, c1oaf needs debugging c1oaf_sat.pngMCL_FF_TF.pdf
    Reply  Wed Oct 2 23:23:02 2019, gautam, Update, CDS, c1oaf DC indicator needs to be green MCL_FF_Test.pdf
Message ID: 14522     Entry time: Mon Apr 8 11:53:17 2019     Reply to this: 14927
Author: gautam 
Type: Update 
Category: CDS 
Subject: c1oaf needs debugging 

I tried restarting c1oaf this weekend to see if turning on the MC length FF would affect the ALS noise performance. I burtrestored the filter settings from March 2016. However, I noticed several possible anomalies, which need debugging. I am not turning the model off because of the possibility of having to reboot all the vertex FEs, but this model is totally unusable right now.

  1. Attachment #1 - the vertex seismometer input produces 1e+20 cts at the output of the feedforward filter. Attachment #2 shows the shape of the feedforward filters - doesn't explain the saturation. Since this is a feedforward loop, a runaway loop can't be the explanation either.
  2. The MC length feedforward control signal is supposed to only go to MC2 - but MC1 and MC3 coil outputs were saturated when I enabled the feedforward.
Attachment 1: c1oaf_sat.png  22 kB  Uploaded Mon Apr 8 13:05:09 2019  | Hide | Hide all
Attachment 2: MCL_FF_TF.pdf  11 kB  Uploaded Mon Apr 8 13:06:46 2019  | Hide | Hide all
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