My question is, what is the purpose of the middle Black/White wire that is between the Green & Gray wires on the connection itself and what is supposed to be connected to it?
That connects into the WeCan output as well. There are 3 outputs for WeCan.
I have a total of 4 WeCan devices plugged into my Carbide. (Liberty II, External Siren Amplifier, and two 16 out-put Expansion Modules)
All the greens are spliced together, all the grays are spliced together, and all the black and white are spliced together.