IM 05C01E12-41E
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What is Dynamic Auto Tune Control?
Dynamic auto tune control is one of the features offered by the temperature controller.
When the controller is turned on or the process variable (PV) starts “hunting”, this mode of control monitors the
behavior of the PV and/or OUT (control output value) to automatically determine the optimum PID constants. This
means that the PID constants may be changed automatically. If this is not desirable for your system, operate the
controller in the normal “PID control”.
If you want to automatically determine the PID constants at the initial startup of the controller, first define the
target setpoint variable (SP) and then turn the controller off once and then back on again. Do not use dynamic auto
tune control for a system where there is interference or continual disturbances.
IMPORTANT
To use dynamic auto tune control,
(1) be sure to turn on the final control element, such as a heater, before starting the control, and
(2) make sure the controlled loop is a closed loop.
If you do not follow these precautions, improper PID constants may be written into the controller. If this
occurs, carry out the following:
• Set the parameter CTL at PID.
• Set the PID constants at the factory-set defaults (P = (upper range-limit – lower range-limit)
×
5%; I =
240 sec.; and D = 60 sec.)
• Set the parameter CTL at SLF.
If the control still doesn’t work properly, stop using the dynamic auto tune control function. Change the
parameter CTL setting to PID and execute auto-tuning to obtain the PID constants.
Summary of Contents for UT150
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