I have a Vista 20-P with 8 inputs. Set up an Alarm Panel Pro with 2 6-Zone Interface modules. Zone 1 was open and using it for Keyswitch after figure out the wiring.
However, some of the connections to the Vista panel have two resistors which allows the Vista to put 2 inputs into the same input on the board and know which is which. I only reviewed the VIsta board for connections and did not cycle through the Honeywell panel which has 12 Zones set up. In the case where there is one resistor going to the Vista board, the wiring back to the Interface module works fine. But on those where there are 2 resistors, the Honeywell Panel will indicate a fault but the Interface Module light doesn’t drop. Has anyone used opto couples to split the signals into two for the Interface Module and still wire back both to the same Vista connection? But I would have to buy another Alarm Panel Pro and 6-Zone Interface? I do have 3 open positions on the Interface Modules - 1 on module 1 and 5-6 on module 2. Inputs 8 and 9 are mapped to alarm circuit.
Or do I punt and return Alarm Panel Pro and 2 modules and go with a conversion kit and junk the panel connection? Conversion kit has 12 inputs. However, have 13 sensors.