VAT 642 Series - Page 76

INSTALLATION Series
642
76/119 Edition 2017-11-24 742280ED
RAMP MODE
Mode = 0
Cocnstant Time
The RAMP TIME is dependent on the adjusted parameter ramp time and is
always the same independent of the control deviation. That means the ramp
time from the actual value to the setpoint value is the adjusted parameter
ramp time value.
Mode = 1
Constant Slope
The RAMP TIME is dependent on the adjusted parameter ramp time and is
different depending on the control deviation. The RAMP TIME is calculated
corresponding to the sensor full scale value (10V). Ramp time = 10 sec.;
ramp time slope is SFS (10V) in 10 Seconds.
In the adaptive pressure controller mode, the RAMP TIME parameter also can be a value to minimize
over- / undershooting. The ramp could be used to harmonize the adaptive control algorithm.
GAIN FACTOR
The GAIN FACOTR is a control parameter to adapt the performance of the pressure control algorithm. A
higher gain results in faster response, higher over- / undershoot of pressure. A lower gain results in
slower response, lower over- / undershoot of pressure.
Example:
Set SENSOR DELAY of the adaptive pressure controller to the value 0.75
Command Pressure
controller
Parameter selection variable Parameter value (seconds)
s:02
A (a) 00 (bb) 0.75 (c)
 s:02A000.75
To optimize adaptive control algorithm, refer to chapter «Tuning of control
performance».