[Brian]

Hi and welcome to the forum.
I have never used a smoke unit on DCC, but you will have to ensure the unit is not in contact with the chassis and then take two wires from the unit back to the motors terminals. This would ensure smoke only emits when the motor is running - Unless you want smoke while the loco is stationary? In which case it will be necessary to connected the smoke unit's wires to one of the lighting outputs. (e.g. Yellow & Blue) Caution here will be needed! .You will need to know the current drawn by the smoke unit before connecting it to the aux outputs of a decoder as these outputs aren't particularly highly rated. Normally 100 Milli amps to 200 Milli amps max. Also if you do connect it across the motor you should ensure the maximum current drawn by both the motor and smoke unit combined are below the rated current of the decoder too. Or you will damage the decoder beyond repair.

Good luck

 

[Brian]

No problem

You must insulate the smoke unit completely away from the chassis and the motor. Once done the two decoder wires will go to the connection that was originally to the motor and the other one to somewhere on the smoke units body (If the body was directly in contact with the chassis originally)
Hope this helps?

 

[Brian]

That decoder should be ok.
Ensure you use the "C" 500Milliamp output for the smoke unit.