Depending on loop controller type, this loop can have 2, 3 or 4 different operating modes (eg. automatic, manual, autotuning, Tracking modes).
Autotuning can be launched if the loop controller is in automatic or manual mode.
Switching to Tracking mode has priority and will possibly cancel the autotuning in progress.
The initial operating mode of the loop can be configured on cold start. You can specify:
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Whether the setpoint is local or remote, as well as the initial local setpoint value.
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Whether the loop controller starts in automatic or manual mode. The initial manual value, if the loop controller is not an ON OFF loop controller
Process Loop With a PID Loop Controller
The following diagram illustrates a process loop with a PID loop controller:
If the output branch sends dotted lines back to OUT_MAN, the limits have been accepted.
If the loop controller is Split Range or Heat/Cool type, there are 2 output branches. In this instance, autotuning and Servo type output without copy are not available.
If the loop controller is an ON OFF type in 2 or 3 states, there is no Feed forward branch or output branch.
