Installation, Operating & Maintenance Instructions
Series 612 DN 25 (I.D. 1”), Logic
VAT Vakuumventile AG, CH-9469 Haag, Switzerland
Tel +41 81 771 61 61 Fax +41 81 771 48 30 [email protected] www.vatvalve.com
289700EB
2011-10-21
32/57
3.10.1.3 Setpoint ramp adjustment
Setpoint ramp effects:
•
Undershoot of pressure
•
Response time
Default value for S
RAMP
is 0. Adjustment range for S
RAMP
is from 0 to 10 s.
This parameter affects the time that is used to decrease / raise pressure between 2 setpoints. Especially in pressure
decrease situations at low flows pressure response can be improved much by adapting setpoint ramp time.
Pressure chart
Choose the applicable formula depending on units you are familiar with.
END
START
SFS
RAMP
P
P
P
S
t
−
•
=
t ramptime
[s]
P
SFS
sensor full scale pressure
S
RAMP
setpoint ramp [s]
P
START
pressure
start
P
END
pressure
end
Adjustment procedure:
1. Start with optimal gain factor and sensor delay time according to preceding tuning steps.
2. Control a typical pressure / flow situation.
3. Control
a
lower pressure.
4. Repeat from step 2 with longer setpoint ramps until best response is achieved.
5. Verify pressure control response for a setpoint raise situation.
Local operation
:
(‘Control View’, ‘Control Performance Analyzer’ or
‘Service Box 2‘)
Remote operation
:
Do configuration in menu ‘Setup / Control Parameter’.
Note: It’s not possible to do ‘Setpoint ramp
adjustment‘ via remote operation.
P
START
P
SFS
t
P
END
Without setpoint ramp optimizing
With setpoint ramp optimizing
