Pro + Interface + Concord 4 -- VREF?

I have a Concord4 installed by my builder with ~7 zones, and I’ve purchased an Alarm Panel Pro + Interface Kit so I can monitor zone status without disrupting my existing key pads.

I’d just like to confirm the VREF before I wire it up. Per my wiring diagram, terminals 3 and 4 provide +12v and GND to the keypads it appears. This is NOT labeled AUX or whatnot, but this strikes me as the only possible place to wire up VREF from the interface kits.

Can anyone confirm? Thanks! :slight_smile:

Shot of the board itself:

Well, I went ahead and gave it a shot. YES, ports 3 and 4 on the Concord4 board are in fact the +12v and GND used for VREF on the interface boards.