HW-Time-Slice Firmware-Filter Software vx2740 Steering Module Reports MVM MVM Vexos MVM-Bug listing MVM TRIUMF Local DS Prototype DS Cryogenic For Shifters BCIT-31 ChronoBox Run Operation DS-DAQ
  CERN DS-Proto0 read-only backup  Not logged in ELOG logo
Message ID: 46     Entry time: 26 Oct 2019 07:33
Author: Sam Hill 
Type: Problem 
Category: Software 
Subject: Test of IV Script 

People:  Simone, Sam, Tom, Edgar

Tested IV curve python script that runs using MIDAS. Measured resistance consistant with resistor specification. elog:46/1

The resistance is attached to ch11, and we called the script (channels go from 0 to 24):
chnum=11 ; python3 iv_curve.py --no_steering --caen_chan $chnum --stop_v 3 --step_v 0.001 --filename ivcurve_`date +%s`_$chnum.txt 

 

Issues:

No readout of trip condiotion therefore python script overides power supply trip and attemps to bring back voltage to next value. Potentially dangerous. Script only terminates with the final voltage value. See attached plot elog:46/1

Script terminated with error message:

Traceback (most recent call last):
  File "iv_curve.py", line 287, in <module>
    iv.run()
  File "iv_curve.py", line 269, in run
    self.set_caen_and_wait_for_readback(voltage)
  File "iv_curve.py", line 223, in set_caen_and_wait_for_readback
    raise RuntimeError("CAEN HV didn't respond to request to set voltage to %s; latest readback voltage is %s" % (voltage, rdb))
RuntimeError: CAEN HV didn't respond to request to set voltage to 2.976; latest readback voltage is 0.052000001072883606

 

Attachment 1: IV_curve_29K.png  11 kB  Uploaded 26 Oct 2019 17:42  | Hide | Hide all
IV_curve_29K.png
ELOG V3.1.4-cb3afcd8