Quick-Ohm QC-PC-PID-01, Руководство пользователя

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04.10.2021 20210927 QC-PC-PID-01-Bedienungsanleitung engl.
Important!!!
Observe the ACTUALTEMP value. This value must move towards the set target value TARGET TEMP .
If the current temperature moves away from the target value, then the Peltier element is poled
incorrectly.
In this case, switch off the supply voltage immediately.
Check the assembly and correct the error.
Then switch on the supply voltage again.
If the actual value moves towards the target value, you can continue. Otherwise, there is still an error
and the operation must be stopped. Correct the error.
The controller now controls the set target temperature.
When the target temperature is reached, the controller regulates. In order to keep the temperature
stable, the control parameters must now be adjusted to the connected assembly.
Adjustment of control parameters
If you have carried out the steps according to the instructions, the controller is now in P-mode. In this
mode, the output supply to the Peltier element is max until the measured temperature on the object
is close to the target temperature. Then the output is turned down. If the measured temperature is
equal to the set target temperature, the output is regulated to zero. Therefor the setpoint can never
be reached in the P control mode. The larger the
KP value, the stronger the controller reacts to a
deviation as the temperature of the object comes closer to the target temperature. If the KP is too
large, the controller will oscillate. In this case the value should be reduced. In this P-mode there
always remains a control deviation.
In order to be able to correct this control deviation, the controller must be given an integral
component
TN . The controller recognizes the control deviation via this and can now compensate for
the deviation. With a value TN > 000 the controller is now in the PI control mode.
It happens that the control does not regulate in a stable way and the temperature oscillates around
the setpoint. Such an oscillation can be corrected via the differential parameter
TV . As this value
increases, the control algorithm reacts more strongly to changes in temperature and prevents the
temperature from being regulated too strongly.
Optimizing the parameters using this method requires a lot of experience. Without this experience,
we recommend the method for determining the parameters according to
Ziegler & Nichols . This
procedure is described below for this controller.