Inv - Setting Of Inverted/Non-Inverted Control - Burkert 8624-2 Standard Instructions De Service

6.6.7 INV - inverted/non-inverted control
Via this function you set the sense of action between the input signal and
the setpoint of the valve (factory setting: NO).
non-inverted control
inverted control
Fig.: inverted/non-inverted control
Example of an inverted control system
In the following system the actual value at the output of the unregulated pump is to
be controlled by changing the opening of the proportional valve in a return flow
loop. If the actual value is too high (x
increased (inverted control).
Working
resistance
Fig.: Example of an inverted control system
1
1
<0), the correcting variable must be
d
Pump
Proportional valve
Sensor
∑ x
y = K (x + T /T
p d A N
∑ x
y = - K (x + T /T
p d A N
non-inverted control ( NO ):
Output signal y of the PI controller
increases with increasing positive
control difference x = w-x.
d
inverted control ( YES ):
Output signal Y of the PI controller
increases with increasing negative
control difference x = w-x.
d
8624-2 Standard - 33
)
d
)
d