Functional Modification of Each Loop

At a Glance

Functions may be added to or deleted from the process control loops in online mode.

Fundamentals

The PLC may be in RUN mode during modifications to the process control loop functions.

WARNING

UNINTENDED EQUIPMENT OPERATION

Perform a channel reconfiguration after:

modification of process loop functions
modification of configuration parameters

(ex: extrapolating the generator function from the function, limiter looping)

Failure to follow these instructions can result in death, serious injury, or equipment damage.

Once the modifications are made, the loop starts in a determined state:

If modifications are made at the Measurement, Setpoint, and Feed forward branch level, the loop performs a warm start.
If modifications are made at the corrector or output level, the loop restarts using the initial operating modes, as previously defined during configuration.

NOTE: any addition or modification of I/O addresses or memory words is prohibited in Online mode. Modifying some branches–such as replacing a simple setpoint by a ratio setpoint–is also prohibited.

NOTE: the totaling function may not be added in Online mode. Its output is an %MF address.

It is not necessary to switch to Configuration mode to edit the initial adjustment parameter values Kp, Ti, and Td.

Operating mode:

In Debugging mode, any change to the adjustment parameters from the task screen affects the current and initial values of said parameters.
Only in the case of the 3 simple loops loop controller, any modification to the initial value will be ignored if the same change is not applied to the configuration parameter also (for example, when adding a function).