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TO PLACE THE CONTROLLER IN AUTOTUNE MODE:
1) We assume that you have configured the controller according to the different menus at this point.
2) If the controller is not already in Standby mode, place it in Standby now as follows. Press and hold the
Mode/Enter
key for three seconds and the display will indicate your current operating mode. Press the
Raise
key or Lower key to select Standby (
). Press Mode key again and the display will
alternate between
and the process value. This will deactivate all outputs.
3) If Setpoint Value has not been entered, adjust the setpoint now by using the Raise or Lower key to set
the desired setpoint.
4) Wait for process to stabilize before proceeding, e.g., in the case of a heating and cooling process, return
to ambient temperature.
5) To initiate Autotuning, press and hold the Mode/Enter key again for three seconds, then press the
Raise or Lower key repeatedly until
appears. Finally, press the Mode/Enter key again.
The display will alternately indicate
and process value as the controller “learns” the proper
proportional band, derivative, and integral values for the process.
6) We strongly recommend that, once autotune is complete, you revisit the Control menu and record the
values of the proportional, derivative and integral action settings that have been determined.
In order for the controller to autotune properly, the setpoint value must be at least 1% of span above or
below the initial setpoint and that the process value is stable before starting the autotune procedure..
Make sure that the Setpoint Target Time parameter is set to OFF.
* Tuning accuracy increases as the spread between ambient and setpoint value increases.
* Tuning should be performed with system in equilibrium (no latent energy remaining).
* If unacceptable overshoot occurs on restart, shut down the process and increase the damping setting.
* If sluggish response is observed, shut down the process and decrease the damping setting.
* Autotuning will attempt to learn the process for a maximum of 60 minutes.
If a tune error condition occurs, the upper display will toggle between
and a numeric error code for three
seconds before the tune process terminates. The controller will automatically go into Standby mode when a
tuning error occurs.
Possible error codes are:
= No PID Device Configured
= Incorrect Output Action
= Insufficient Setpoint-Process Value Deviation
= Invalid Tune Results
= Tune Timeout
How Do I Get Here?
1. From the
mode, use the
or key to
adjust the setpoint to
the desired process
value.
2. Assuming the
process is stable,
press until
appears.
3. Press or
until
appears.
4. Press to
start the autotune
operation.
