Here is a look at the (EOB) control board. Note the (4) wires to the smoke unit. There is a low fluid level (??thermistor??) as part of the smoke unit to inhibit smoke resistor burn out. There is only one track feed AC to the board. Depending on how the mother board was programmed, there were different functions/voltages.
TAS turbo smoke unit. From the resource section of Legacy TMCC control