Rockwell Automation 1746-BTM Barrel Temperature Control Module User Manual - Manual (Page 50)

Publication 1746-UM010B-EN-P - April 2001
5-4 Control and Autotune a Loop
Items to check before autotune
Each loop must:
•
be configured with a valid M1 file and no errors (N10:212-215)
•
be set for barrel mode
•
be set in manual mode and that run setpoints are selected,
starting from a cold start. If not starting from a cold start, at a
steady state temperature.
•
have the TPO period set considerably smaller than the system
dead time.
A good place to start is 5 or 10 seconds.
•
not have any existing alarm conditions that could cause
problems (such as a TC break)
Autotune barrel control applications
Autotune enables the module to compute PID values for optimum
temperature control. You must load the program and use the
following procedure to autotune the module.
For barrel control, better results are achieved when you autotune all
loops associated with the barrel at the same time. After autotune,
each zone will return to the mode (auto or manual) that was selected
beforehand.
IMPORTANT
For best results, start from room temperature (cold
start).