Controller Optimization - JUMO 202550 Operating Instructions Manual

27.2 Controller optimization

Optimum
adjustment
The optimum adaptation of the controller to the control loop can be tested by
recording the starting phase.
The following diagrams (referred to the PID action) indicate where the
adjustments may be incorrect, and how they can be rectified.
It can be seen that a slower control action with higher stability can be achieved
by increasing either the proportional band Pb or the reset time rt.
A smaller proportional band Pb and / or a shorter reset time rt will result in a
control action with less damping.
x
w
optimum
x
w
rt, dt too small
x
w
Pb too small
t
x
w
t
rt, dt too large
x
w
t
Pb too large
27 Controller
t
t
85