VAT 653 Series Installation, Operating, & Maintenance Instructions page 52

Gain factor adjustment
The gain factor effects: Stability, Response time
Adjustment range is from 0.0001 to 7.5.
- Higher gain results in: faster response / higher over- / undershoot of pressure
- Lower gain results in: slower response/ lower over- / undershoot of pressure
Adjustment procedure:
1. Start with gain factor 1.0
2. Open valve.
3. Control a typical pressure / flow situation.
4. Repeat from step 2 with lower (higher) gain factors until optimal pressure response is achieved and
stability is ok.
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.
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».
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INSTALLATION
Normally adjustments down to gain factors of 0.42 should lead to good results.
Otherwise you may need to improve sensor connection. Refer to «Requirements to
sensor connection».
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.
Edition 2019-06-05
Series 65
982156EB