VAT 642 Series - Page 51

Series 642 INSTALLATION
813316EB Edition 2017-11-24 51/
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4.7.1.2 Sensor delay adjustment
Sensor delay adjustment effects: Stability
Adjustment range is from 0 to 1.0s.
Pipes and orifices for sensor attachment delay response time and so badly impact pressure control
stability.
By adapting this parameter to the approximate delay time stability problems can be reduced. But control
response time will be slowed down by this measure.
Whenever possible sensors should be attached to the chamber according to
«Requirements to sensor connection». This is the most effective measure against
stability issues. If your gauge attachment fulfills these criteria do not use this
parameter.
Adjustment procedure:
1. Start with gain factor 1.0 and sensor delay 0s.
2. Open valve.
3. Control a typical pressure / flow situation.
4. Repeat from step 2 with higher sensor delays until best possible stability is achieved.
5. Adjustment gain factor again. Refer to «Gain factor adjustment».
Local operation:
(‘Control Performance Analyzer’ or ‘Service Box 2‘)
Remote operation:
With CPA:
• Do the ‘Sensor Delay’ adjustment in menu
‘Pressure Control’ / ‘Setup’ / ‘adaptive
downstream’.
With SB2:
• Do the ‘Sensor Delay’ adjustment in menu
‘Setup / Control Parameter’
It’s not possible via «Remote
operation»