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A-96.250.741 / 050218
AMI INSPECTOR Hydrogen
Program List and Explanations
As control
output
Signal outputs can be used for driving control units. We distinguish
different kinds of controls:
P-controller:
The controller action is proportional to the devia-
tion from the setpoint. The controller is characterized by the
P-Band. In the steady-state, the setpoint will never be
reached. The deviation is called steady-state error.
Parameters: setpoint, P-Band
PI-controller:
The combination of a P-controller with an
I-controller will minimize the steady-state error. If the reset
time is set to zero, the I-controller is switched off.
Parameters: setpoint, P-Band, reset time.
PD-controller:
The combination of a P-controller with a
D-controller will minimize the response time to a fast change
of the process value. If the derivative time is set to zero, the
D-controller is switched off.
Parameters: setpoint, P-Band, derivative time.
PID-controller:
The combination of a P-, an I - and a D-con-
troller allows a proper control of the process.
Parameters: setpoint, P-Band, reset time, derivative time.
Ziegler-Nichols method for the optimization of a PID controller:
Parameters
: Setpoint, P-Band, Reset time, Derivative time
The point of intersection of the tangent with the respective axis will
result in the parameters a and L.
Consult the manual of the control unit for connecting and
programming details. Choose control upwards or downwards.
A
B
X
Response to maximum control output
Tangent on the inflection point
Time
Xp
Tn
Tv
= 1.2/a
= 2L
= L/2
X
Y
B
A
L
a
