Manual Setting Of The Control Parameters - Siemens SIPART DR22 Manual

Manual
D PiD controller (control signal P* = low)
-- Set the desired setpoint and set the control difference to zero in manual operation.
-- Switch to automatic operation.
-- Increase Kp slowly until the control loop tends to oscillate due to slight setpoint changes.
-- Switch Tv from oFF) to 1 s.
-- Increase Tv until the oscillations disappear.
-- Increase Kp slowly again until the oscillations reappear.
-- Repeat the setting according to the previous two steps until the oscillations cannot be
eliminated again.
-- Reduce Tv and Kp slightly until the oscillations stop.
-- Reduce Tn until the control loop tends to oscillate again.
-- Increase Tn slightly until the tendency to oscillate disappears.
4.7

Manual setting of the control parameters

after the transient function
If the transient function of the controlled system is active or can be determined, the control pa-
rameters can be set according to the setting guidelines specified in the literature. The transient
function can be recorded in the „Manual mode" position of the controller by a sudden change in
the manipulated variable and the course of the controlled variable registered with a recorder.
This will roughly give a transient function corresponding to 4-2.
Good average values from the setting data of several authors give the following rules of thumb:
P-controller:
Proportional action factor
Pi-controller:
Proportional action factor
Integral action time
PiD controller:
Proportional action factor
·
Integral action time
Derivative action time
SIPART DR22 6DR2210
C79000-G7476-C154-03
Tg
≈
Kp
Tu · Ks
Tg
≈
Kp 0.8 ·
Tu Ks
·
≈
Tn 3 Tu
·
Tg
≈
Kp 1.2
Tu · Ks
≈
Tn Tu
≈
Tv 0,4 Tu
·
4 Commissioning
4.7 Manual setting of the control parameters
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