Cascading PID Loops may cause download errors

Applies To:

PAC Control Professional
PAC Control Basic

Versions Affected:

Problem was introduced in version: ioControl R5.1a
In all versions of PAC Control
Problem is fixed in version: R9.6a

Resolved In Version:

Problem is fixed in version: R9.6a

Symptoms:

If the output of one PID loop is used as the input for another PID loop, an 'Undefined Command' error during download. message may appear when the strategy is downloaded to the control engine.

Workaround:

Use strategy logic in a chart to move the output of the first PID to the second PID.

Resolution:

Opto 22 has resolved this issue.

Questions?

Contact: Opto 22 Product Support.
Phone: 800-835-6786 or 951-695-3080
Email: support@opto22.com

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