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Milltronics SF 500 - INSTRUCTION MANUAL
7ML19985CN01
mmm
mm
PI
D Co
ntr
ol
Figure 4
Figure 5
Figure 6
9.
The D term is not critical in most pre-feeder applications. The purpose of the D term
is to anticipate where the process is heading by looking at the time rate and
direction of change of the process variable. The D term becomes very useful in
applications where the material control point is far away from the measuring point,
e.g. a long screw feeder more than a few seconds process time from the flowmeter.
SETPOINT
I term is too high
SETPOINT
I term is too low
SETPOINT
I term is correctly set
Select manual to program PID
parameters.