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5.1.1 Autotune AT
Start Autotune AT with the load cool. A short tuning cycle occurs at
75% setpoint during warm up. New PID values are automatically
entered and the temperature rises to setpoint.
Autotuned Parameters Autotune Limits
Entered automatically:
Proportional Band/Gain 0.5%-20% range
Integral time/Reset 0.2-43.5 min
Derivative time/Rate 1.0-255 sec
DAC/Approach control 0.5-9.0 x gain
Proportional cycle time 0.8-81.9 sec
calculated but for safety reasons needs manual confirmation.
Refer to Figure 5-1.
Figure 5-1. Autotune AT
Temperature
setpoint
tuning
DAC
PID
AT tuning
75% SP
Time
Start AT
(100% output power)
new PID values
entered and
output
power re-applied
SECTION 5 TUNING
5.1 AUTOTUNE
Two types of autotune are provided to ensure optimum control of a
wide spread of applications.
Autotune AT: normal method, tunes during warm up (start up).
Autotune PT (push-to-tune): for difficult applications, fine tunes at
setpoint.