Passing an analog value from PLC to DCS


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I want to pass an analog value from a 1769-OF8C AO module to a Series C (C300) Honeywell Experion AI IOMA.

The 1769-OF8C Datasheet can be found here

The AI IOM can have its signal wire taken to TB2, and bypass the 24V supply provided by the module. The signal is grounded internally (JP17 for channel 13).

So, with the PLC providing a loop powered signal, and it being wired in to the non-loop powered terminal block of the AI IOM, my concern now is ground loop issues.

According to Honeywell's IOM manual, by default, the negative of the measurement amplifier is ground to the system. On channels 13 - 16, a jumper can be cut to disable this system grounding.

On the PLC side, I am unsure of whether it is grounded or not. Additionally, if I was to use the system ground of the AI, it would ground all AO's of the PLC as they share the same AO COMMON.

Can anyone provide further clarification on this?