Smoke unit modify on USRA 0-6-0 Smoky Mountain Express

[monty27]

Would it be possible to connect the smoke generating unit to the headlight circuit, thereby being able to shut the smoke  unit off with the F10 button as needed. Thus applying more voltage to create smoke at any speed.
When operating at low speeds there is no smoke. This Locomotive is used to pull a consist of Denver & Rio Grande Western scenic cars.

[Doneldon]

monty-

The smoke effect is no better than fair at its best, which is continuous running at full speed, and it presents pollution problems when it does operate, specifically mineral oil deposits on your track and locomotive. In my opinion, it's just not worth the mess. However, if you want the most smoke, you will have to send full current to the smoke unit. With DCC, you'd have to connect directly to track power but the overvoltage might burn out the smoke generator. Perhaps you can add a resistor to lower the track voltage. A direct link to the track on a DC layout won't be of any help because the track voltage varies from zero on up to control your loco's speed.
                                                                                               -- D

[Tom M.]

In DCC, most smoke units draw more amps than decoder functions are rated for.  As such, I use an available DCC function to control a micro switch.  The micro switch then controls feeding track power to the smoke unit.  ESU has a very good and affordable micro switch.

I have mostly used Seuthe smoke units in customer locos when they've requested smoke.  In HO, most are rated at 12-16 volts.  A typical DCC system set to HO mode has 12-14 volts on the rails.  At that rating, they will not burn out unless you allow them to go dry.  The heating element burns out quickly if it runs out of oil.  That's why it is best to control it off an independent function.

If the decoder does not have a spare unused function available, it is usually not too difficult to install an auxiliary function only decoder.  TCS offers both two and 4 function decoders.  Good luck.

Tom