Hello Experts - I want to install an LGB 65853 5 volt smoke generator into an LGB Chloe small locomotive onto a 4 amp Soundtraxx Tsunami2 4400 Power/Sound Decoder. The decoder does not have a specific connection for a smoke unit but does have some additional lighting connections: FX3 - FX6. The specifications state that the six function lighting outputs are rated for 100mA each…do not exceed this current rating. Another spec states: The Function Common is rated at track voltage minus 1.5v…this rating will vary between command stations and layouts. My question to George at the Soundtraxx Technical Dept and his response are below:

"Hi George - I want to attach an LGB# 65853 smoke generator 5 volts to the decoder’s FX3 connection. It appears that the lighting connection and the FX connections are all 12 volts. The only guidance I see in the documentation is that to reduce the lighting voltage use a resistor. What value resistor do I need to use to power the 5 volt smoke unit?

Tom, you can, but… you will need to drop the voltage with resistors. The other factor is each output is good for 300mA. Just be sure your smoke unit draws less than 300 mA at 5v (with resistors) so you’ll be below the current limits of the FX3.
Let me know if you need further guidance.
Thank you!"

What value resistor do I need to reduce the 10.5 volts (12 volts - 1.5 volts) for the smoke unit connected to FX3? Does anyone know what the mA draw is for LGB 5 volt smoke unit?

This seems kind of complicated sorting all this out so the 5 volt smoke unit doesn’t harm the decoder. I’m thinking as an alternative, just connecting an LGB 18 volt or 24 volt smoke unit directly to track power instead of through the Soundtraxx decoder…many of the older LGB locomotives powered the installed smoke units as always “on” using a 18 - 24 volt smoke unit, later the 5 volt units.

The short version of the Soundtraxx install instructions are attached…very detailed install and configuration documents are available on their Website for this decoder.

Thoughts please…thanks!

I’m thinking as an alternative, just connecting an LGB 18 volt or 24 volt smoke unit directly to track power instead of through the Soundtraxx decoder…

That would be the better option. Smoke units are power hungry and can draw a half an amp or more.

David - Do the 18 or 24 volt smoke units burn at a high temperature than a 5 volt unit? I don’t want the smoke unit to start to melt the small smoke stack on the LGB Chloe loco! I put the smoke stack with a the five volt smoke unit install in it wiring it to a DC power supply with a 5 volt regulator connected. It worked fine but the smoke stack cover got a little “sweat” on it, but didn’t see to bother it.

Interesting.

First off, the published spec is 100ma per “output” but he says to keep under 300ma?

Also the lighting “outputs” are not outputs but inputs, they switch to ground, or as they say within 1.5v of ground.

So, you get a 5v regulator, and then power that from the rectified track voltage (after the fw rectifier on the decoder)… then feed that 5 volts to the heater and then to the function “output”.

First, I would double check the current draw at 5 volts, both dry and full of fluid… just to be sure.

Second, I am distrustful of the 300ma “verbal specification”, but if he will replace it under warranty, worth a try.

ahhh… I just went to their site, the 4400 is rated 400ma each “output”… but there is no “total” for the sum of all outputs.

Furthermore, I cannot find a spec sheet for it, none of the manuals I could find gave electrical characteristics… weird…

Normally, if you don’t have a dedicated high current “output” you would add a relay.

Note, for the same amount of smoke, the 18v unit should draw less than 1/3 the current the 5v unit does…

Greg

Greg - As David states, I’m thinking it’s jut easier to wire to track power an 18 v or 24 v unit. I don’t have room in the Chloe to place a 5 v regulator…very tight space constraints. See my response to David just before your message.

Tom

Yes, I agree, notice my closing sentence… (https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-wink.gif)(was always told the last thought you leave people with is the one they normally remember the most)

BTW 5v 3 terminal regulator is about the size of a stack of 4 dimes…

Notice the post times of you and I, identical, but I started writing it much before.

Greg

Since the stack is touching the smoke generator at the top of the generator, I would not think it would get hot enough there to cause any problems, But I would try testing the generator outside of the stack to see how hot that part gets. The other stacks on LGB locomotives are plastic too, but they are thicker plastic. That said, those stacks don’t warp nor melt, but again they are thicker. So an all up test outside of the plastic stack to answer the “how hot” question would be a good idea.

Get the HO seuthe smoke unit as it is small enough to fit in the stack and comes in 22 volt 70ma version. Type 2

http://www.gaugemaster.com/seuthe.html

David Maynard said:

Since the stack is touching the smoke generator at the top of the generator, I would not think it would get hot enough there to cause any problems, But I would try testing the generator outside of the stack to see how hot that part gets. The other stacks on LGB locomotives are plastic too, but they are thicker plastic. That said, those stacks don’t warp nor melt, but again they are thicker. So an all up test outside of the plastic stack to answer the “how hot” question would be a good idea.

David - Yes, good idea just to play it safe…I’ll do that with the 18 volt unit I have ordered. I also ordered a 24 volt unit for backup. I think my customer buying the Chloe uses a NCE DCC system which I believe is 18 volts, so that LGB smoke unit should be the right one. My Massoth system puts out 22 volts.

Dan Pierce said:

Get the HO seuthe smoke unit as it is small enough to fit in the stack and comes in 22 volt 70ma version. Type 2

http://www.gaugemaster.com/seuthe.html

Dan, thanks for the suggestion. I already expanded the smoke stack top’s hole to fit the LGB smoke unit…see photos in my prior posting. But I’ll keep the GO unit in my inventory of options for the future. I’ve decided to bypass the decoder, too many complications with resistors, regulators, etc. Instead I’m going to direct wire the LGB 18 volt smoke unit to track power where the four set of electrical pins come out of the front of the Chloe motor block.

Have you ever measured the current draw of an LGB 5 volt smoke unit and know what the draw is? I recently bought a new Fluke 115 Multimeter but haven’t taken the time to learn how to use it yet.

I’m also surprised that Sountraxx didn’t design their Tsunmani2 4400 for O and Large Scale with a 5 volt smoke connection. Maybe because it has so many sound options on it that a smoke unit would overload its capacity…someone previously mentioned that smoke units are current hogs.

Tom

The 5 and 10 amp NCE systems will put out about 21.6 volts max (there is an adjustment pot).

Of course track voltage will also always be limited by that and 3 volts lower than the DC input voltage.

For large scale, I would not use 18v units. By the way, the marker lights on an Aristo mallet are 18v and you can watch them burn out on 22-23v DCC track voltage… don’t ask me how I know.

Greg

Greg Elmassian said:

The 5 and 10 amp NCE systems will put out about 21.6 volts max (there is an adjustment pot).

Of course track voltage will also always be limited by that and 3 volts lower than the DC input voltage.

For large scale, I would not use 18v units. By the way, the marker lights on an Aristo mallet are 18v and you can watch them burn out on 22-23v DCC track voltage… don’t ask me how I know.

Greg

Greg - So, I have both an LGB 18v. and 24v. smoke units on order. If I use the 24v. unit, do you think the NCE 21.6 volts track power will be sufficient to burn smoke fluid well? I guess the other option is to add a resistor onto the line going to an 18 volt smoke unit…there is room to accommodate 1 - 2 resistors in the smoke stack. Of course I can test the 24 volt unit with 21 volts to see how it works…should have my shipment this Thursday.

well…

That’s a subjective term, so you will give you my subjective response: I don’t think any of the non-fan driven, non-microprocessor controlled smoke units “burn well”.

By their uncontrolled, unmonitored nature, and the restrictions in design, they cannot in my opinion as an engineer. You are running a heating element open loop with a resistance that varies and unregulated. The only way this is successful is to run conservatively, i.e. so it will not burn out in any condition of “fullness” of fluid. So, since it has to run conservatively to ensure not burning out, volumes of smoke seems out of the question.

Maybe you could experiment with the 18v unit on a 24v system and “dim” the function, but I’m also not real comfortable with PWM output to the heater since it is basically an inductor. (has anyone suggested a snubbing diode yet?) This might let you “tune” the output, and of course turn it off when dry.

That’s my opinion and experience. If you want “good” smoke, I would go with either a self contained system like the massoth, or a “direct drive” system from the decoder.

Best, Greg

If you want “good” smoke, I would go with either a self contained system like the massoth, or a “direct drive” system from the decoder.

Yes, that’s a good idea, but not really applicable to the Chloe. The boiler is diminutive, and the stack doesn’t have a lot of room neither.

Right, no “great smoking” solution for the Chloe…

As I finished up my post, IF you can run enough current through the function output AND IF you can “dim” the output AND IF you can get a 24v unit AND IF you add a snubber diode across the element to protect from transients, that MIGHT be your best bet.

That would be my best suggestion for the Chloe…

Greg

Greg and David - Thanks for all the suggestions and advice. As David mentioned, the LGB Chloe, like the LGB Olomana, is very space constrained for installing anything fancy for a smoker. So I’ll experiment around just using direct track power by-passing the decoder which I locate in the rear fuel bunker. I’ve installed these Soundtraxx Tsunmani2 4400 decoders into about 6 - 7 of these LGB Olomana/Chloe locos that I’ve sold to people, or they sent me their loco for the installation…but this is the first time someone really wanted me to add a smoker.

Looking at the pictures, LGB uses the yellow/brown wired smoke unit and the seuthe rating is 11 to 16 volts. 140 ma rating.

LGB 24 volt unit is 2 white wires and the seuthe unit is 16 to 22 volts and 100ma (this should be the hot rating, just a guess).

LGB 5 volt unit with black/white wired smoke unit and the seuthe rating is 4.8 to 6 volts and 260ma.

Interesting that the Seuthe colored wires is much the same as to what LGB is using.

Greg - I’m not going to use the Soundtraxx decoder to wire the smoke unit. Just use DCC 20 volts direct track power. So, according to Dan Pierce’s current draw data, the 18 volt and 24 volt smoke units draw the least current 140ma and 100ma (and heat). So, I could use a very small regulator at 18 volts…I saw some very small ones on Amazon today that will likely fit into either the Chloe smoke stack or in the Chloe motor block pin compartment. Or I could test the 24 volt smoke unit without a regulator. I’m not looking for perfection, just produce some smoke even if irradic. Thoughts?

Tom, remember that the regulator ic’s (the standard 3 terminal 78xx series) need a few volts “overhead” to regulate, so if you want to regulate at 18 volts, your input needs to be higher…

What DCC track voltage are you designing for? Start there.

You may need to use an LDO regulator.

Greg

Greg - The DCC track power is either 18 volts or 22 volts…I’ve asked my customer to provide that info to me. If it’s the 18 volts, then I guess I’m destined to use the 5 volt smoke unit instead of the 18 volt unit…or see how the 24 volt unit performs on 18 volts.

I don’t know what an LDO regulator is?

I’ve seen some pretty small adjustable down voltage regulators too on Amazon and eBay. The first photo is the smalla regulators I use in locos or rolling stock but it’s too large for the Chloe. The second photo shows an adjustable one I found on eBay that’s the size of a quarter: Variable or fixed input 4.5 - 28 volts DC; Constant adjustable output .8 - 20 volts DC; Rated current 2A, 3A max. Looks like a good fit for the Chloe.

Thoughts (and what’s an LDO regulator)?

Thanks