Autotuning
In order for the controller to autotune properly, the setpoint value must be at least 1% of span above or below the initial process value. Make sure that the Setpoint Target Time parameter is set to OFF.
Tuning accuracy increas- es as the spread between ambient and setpoint value increases.
Tuning should be performed with system in equilibrium (no latent energy remaining).
To place the controller in Autotune mode:
1)Configure the controller by following the directions for Initial Setup Sequence through Step 3 on page 7. Set damping parameter. (See page 22.)
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. 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 pro- cess value. This will deactivate all outputs.
3)If Setpoint Value has not been entered, adjust 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)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. 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.
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