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Is there a good aftermarket chuffer that does NOT require TMCC that can take advantage of the flywheel encoder strip from a PS2 loco and drive a PS1 smoke unit?

I've chosen the PS1 smoke unit because it has on-board bridge and voltage regulation, which I'm thinking I would need to add separate if I used a PS2 smoke unit.

I would like toc connect one output of my DCC controller to flip a dual-circuit relay that connects the PS1 smoke resistors directly to my battery or track power (whichever one happens to be active at the time) and then pulse the fan on some kind of separate chuff signal.  The motor has a striped flywheel and the encoder, but from what I can tell the SuperChuffer requires TMCC to process the chuffing output.

I'd like to avoid the magnet / reed switch if there's any way to use the optical setup that the PS2 already had the infrastructure for.  Not much room for magnets on the inside of these wheel rims best I can tell.


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The Super-Chuffer II and the Chuff-Generator don't require TMCC, although it was designed with command operation in mind.  I've done several conventional operation installations with the Super-Chuffer, I just add a large aux cap to allow operation at lower voltages that are experienced during conventional operation.  Since you're talking DCC with constant track voltage, you'll have sufficient voltage for the Super-Chuffer II to run with no problem.

If you're looking for a chuff pulse, then the Chuff-Generator could be used to generate that pulse, no magnets required, it would use the same tach strip as was used for the DCS.

If you look at the wiring diagram for a complete Super-Chuffer II and Chuff-Generator installation, you'll see that the only inputs from the TMCC board are easily replaced by outputs from your DCC setup.

The headlight in for Rule-17 lighting is just voltage more than 3 volts and it can be positive or negative.  You also can simply not use the Rule-17 lighting feature if your decoder already performs that function.  Similarly, the smoke power in is just sensing when the heater is active so it can enable the fan control.  The chuff out is a 5V logic signal from the uP on the Chuff-Generator, and newer versions of the Chuff-Generator have just started using an open drain FET driver for the chuff output.  Either should be suitable for your purposes.

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Super-Chuffer II & Chuff Generator Example


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  • Super-Chuffer II & Chuff Generator Example

Interesting, John.  So the chuff-generator generates a 5V pulse signal, but I take it that I can't use that 5V to directly pule the motor.  It has to go through the super chuffer, which then switches ground for the smoke motor in those pulses?  Is the logic for the pulse rate done on the chuff generator board itself, or is that done on the super chuffer?

Just trying to figure out if I need both to do what I'm trying.  I can set the output on my DCC to switch the whole smoke circuit on and off from the DCC power I think easy enough.  But obviously the DCC doesn't have any provisions for handling the pulse signal.

I don't anticipate using any of the light features since the decoder has them covered atm.

Correct, the Chuff-Generator generates the 5V pulse.  It's not strong enough to drive the motor, and it also isn't timed to generate the proper motor run time.

The Super-Chuffer not only times the pulse for the best looking chuff, it also gives you low speed fan at idle when no chuffs are coming in.  If the Chuff-Generator were driving the motor directly, you'd get no smoke when stopped and the wick would be cooking as well when stopped.

It does appear you'd need both to do the whole job as you describe it.

John, I'm wiring up the super chuffer now and I just want to be absolutely certain that it's ok for me to wire 12VDC directly to pins 1 and 2, with the positive going to pin 1 and negative to pin 2. This would be when I'm running on battery power.

When I switch to track power, it will be fed AC probably around 14 to 16 volts.

The diagram shows AC inputs, I'm assuming that there's just an on board bridge to convert to DC?

The signal that the DCC decoder will send to the super chuffer (to say that the smoke unit is to be switched on) is 10.5Vdc. Is that ok, or do I need to step that down to 5V first?

Edit: now that I'm looking at this, I still need a relay to connect the heater to track/ battery power don't I? For some reason I thought that the TMCC/ERR setup in the diagram was telling the chuffer to provide the current from the track to the heater, but after looking again, it looks like the ERR board actually provides the full current to the heater. My DCC board can't do that, it will only do 400ma so I still need a relay, right? Or am I looking at it wrong?

Last edited by Jeff_the_Coaster_Guy

Yep, pin-1 & pin-2 are the input power, I normally wire 18V AC track power to them.

There's not a bridge, it's a single diode.  The half-wave is for a specific reason, TMCC is a common ground reference for all the signals, so I couldn't have a bridge rectifier or I'd have had to arrange isolation for all the signals!  That being the case, the signals coming into the Super-Chuffer II will all be referenced to pin-2 as their common.

There is no problem putting anything up to track voltage on pin-9.  Pin-9 and pin-3 (Headlight in) have input circuitry designed to handle up to full track voltage.

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