AMI Oxytrace QED
Program List and Explanations
A-96.250.531 / 300617 77
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 program-
ming 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
To Next Page
Loading...
