Control of CAEN HV using PVSS

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Control of CAEN HV using PVSS
Ombretta Pinazza ALICE TOF INFN Bologna
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Layout of MRPC Module HV tests
The Module has undergone a long term test (test
beam on October 2003, and cosmic test from Dec
17 2003 to March 12 2004)
CAEN SY2527 with A1534P, A1534N boards
distribution box
MRPC Module 0
PC W2000 with PVSS
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Control of CAEN HV with PVSS

• We have been developing a PVSS monitoring system
  since June 2003
• A datapoint for A1534 N-P boards has been created
• Test of PVSS II version 2.12.1 and 3.0 RC1 (FW
  2.04)
• Custom panels for graphical monitoring, voltage
  settings, data archiving

EXAMPLE A quick look panel with
voltage setting boxes, showing current and
voltage trends. Archiving is performed with
a simple C-like script writing an ASCII file
Works with PVSS II 2.12.1 on W2K and 3.0 RC1 on
W2K and WXP
I_
V_
I
V
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Problems with PVSS II (2.12.1 and 3.0 RC1)

• OPC connection too weak, update timing impossible
  to control
• (in version 3 the OPC connection is better
  but still not fully working)
• Actual OPC configuration not visible
• Trending tool poor and inaccurate
• Device Editor Navigator not working properly
• Archiving and Excel report unusable

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Strange errors still occur...
PVSS 2
PVSS 3
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OPC timing control
Update timing is our main concern! A sudden
current variation might need a prompt reply.
Quicklook graphs and alarms need to be
instantly updated.

• OPC configuration may be controlled by two
  values
• update rate (ms)
• refresh timer (s)

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Some statistics on OPC timing(1/4)
t (s)
t (s)
t (s)
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Some statistics on OPC timing(2/4)
lt?tgt 2.5 s
lt?tgt 7 s
PVSS 2 first day
PVSS 2 after three days
both UR100 ms and RT1s
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Some statistics on OPC timing(3/4)
lt?tgt 2.3 s
lt?tgt 2.3 s
PVSS 3 1000/1
PVSS 3 100/1
it seems to be more stable than PVSS 2
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Some statistics on OPC timing(4/4)
default
NOTE Performances become worse with time and CPU
load
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Conclusions

• PVSS 3 performance improved with respect to PVSS
  2
• Graphical tool for archived data still
  insufficient
• OPC response to data variation too slow and not
  under control yet