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This tuning method may be used for non-temperature control processes or if the spread between ambient
temperature and process operating temperature is small. While some processes other than heat or cool
applications may respond successfully to autotuning procedures, the controller may need to be manually
tuned for non-temperature processes. For best results, use a recording device when tuning with this
method.
1) For temperature control processes, disable any cooling device used.
2) With the power off and the controller NOT in the Key Lockout security level, apply power and
immediately put the controller in Standby mode by pressing the Mode/ Enter key for three seconds,
the Raise key until StbY appears and press the Mode/Enter key again.
3) If you have a direct-acting output, it must be disabled before proceeding further
a)
OutP
01.tY
OFF.
4) Under the Control menu, make sure that the derivative term dEr, the offset term OFFS , and the integral
term Int are all set to zero, and the proportional band Pb1 or Pb2 is set to the maximum setting.
5) Adjust setpoint to the desired value with the Raise/Lower keys.
6) Press the Mode/Enter key for four seconds, the Raise key twice to get to nor, then press the
Mode/Enter key again to return the controller to normal operation.
7) While monitoring the recording device, decrease the proportional band value by repeatedly halving the
value until a small, sustained temperature oscillation is observed. Measure the period of one cycle of
oscillation (“T” on the diagram below).
8) Divide the period of oscillation (T) by eight. The resulting number is the correct Derivative dEr time in
seconds.
9) Multiply this number by four. This is the correct Integral Int time in seconds.
10) Multiply the bandwidth value (obtained in Step 7 above) by 1.66 and enter this as the new proportional
band Pb1 value.
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