Incorrect scaled analog output XVAL when strategy is initially run

Applies To:

SNAP-PAC-R1
SNAP-PAC-R2
SNAP-PAC-R1-W
SNAP-PAC-R2-W
SNAP-PAC-EB1
SNAP-PAC-EB2
SNAP-PAC-EB1-W
SNAP-PAC-EB2-W

Versions Affected:

Problem was discovered in version: R9.1b

Symptoms:

A scaled analog output module's XVAL is initially incorrect until a command in the PAC Control strategy writes to the analog module.

For example: A SNAP-AOV-23 has the Lower Scaled value set to 4mA (Actual) = 0% (Scaled) and the Upper Scaled value set to 20mA (Actual) = 100% (Scaled). When the strategy is initially run and the point is not manipulated by the strategy, the XVAL value for the point is 4% of the scaled value instead of 0%. When the strategy writes any valid value between 0% to 100%, the module output XVAL begins to report the value correctly.

Workaround:

To work around this problem, after the Upper Scale Units or Lower Scale Units is changed, store the configuration to flash with PAC Manager. Next, reset the I/O unit with PAC Manager or turn the unit off and on. This causes the unit to immediately use the Lower Scale Value setting.

Questions?

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

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