Large Scale Central

USA trains smoke unit

Modeling Motive Power
#1

Does anyone know max. voltage for these units (newer fan version)
Dual units in a GP-38-2.
Can it be connected direct to dcc track power?

David

#2

Fan max is 5v.

If you have the fan going, you can push about 9 volts continuously, 12 volts for a short time into the smoke element. Do NOT run at 9v if you have the fan off. Don’t even think of 12v without the fan going full bore.

The reservoir is small, do NOT run it dry at 9 volts.

Do not exceed these voltages or you will burn it up.

Greg

#3

Greg,
I thought those voltages were controlled by the board the
Heater and fan plug into. What voltage can I run to that board?
Can it handle track voltage?

David

#4

The board will take track voltage and has 2 regulators on it, one for the fan and the other the heater.

I thought you were asking about the smoke unit itself.

By the way, it does NOT run max voltage to either the fan or the heater…

Greg

#5

Thanks

My plan is to connect one of the aristocraft smoke boards used
on the revolution to a function outlet on a dcc decoder.
(Massoth XXL) and then use it to turn on/off the dcc track voltage to the smoke board. Is that a reasonable plan?

Thanks,
David

Board. Is that a reasonable plan?

#6

  1. if you leave the current electronics on the aristo unit, turning it on and off is the worst thing you can do. It’s overheat protection circuit is a microprocessor, and it sort of does a few minutes of operation to try to calibrate, and interrupting the power resets this calibration. I can do into more detail of exactly why this happens, but it is NOT a good idea in the least. To be clear, turning it on for a session is fine… turning it on and off frequently is not.

  2. if you bypass the electronics, you need to do a bit more research on how to directly drive the fan and heater.

By the way, the Aristo electronics were designed for about 18 volts, running at 24 volts may cause premature failures, I can also explain further, but again take my word. Years back, 3 of us did some detailed tests on about 27 of these units, we know them pretty well.

Greg

#7

Greg,
Sorry, I must be explaining this badly.
I know the crest smoke control board CRE57073
used on the revolution works on a dcc decoder as I have had 7
of them connected to a Massoth xl decoder for over a year.
They turn on or off the power from a 16.8v battery to control lights
on my passenger train.

My concern on the gp-38-2 loco is the dcc track power.
Can I run it through the CRE57073 switch to control the
USA train smoke units?

David

#8

Sorry, I get you now.

look at this page: http://www.trainelectronics.com/Aux_Interface/index.html

(image from Dave Bodnar’s site)

The smoke control board has a full wave bridge on it, so it should rectify dcc track power to run it, but there is no filtering. It might work but you might need to add a small filter cap after the bridge.

The input power just runs the logic to turn the FET transistors in the IC on and off.

So, it might work, but why not just run a small reed relay from the decoder function output? put a “Snubbing” diode across the relay coil just to be sure. You should be able to find a 24v reed relay with a 5 amp contact.

Greg

#9

Thanks Greg,

I will try the crest board first.
I have 50+ of them so if this works it will be
A good way to use them up.
If not I will go with a relay.

David