# Need help with Digitrax track voltage



## jockey31 (3 mo ago)

Hello, I am a lifetime model railroader, but of course still always learning. Just got back into HO scale and I am using a *Digitrax Zepher* and *UT6 *to run a small home office/man cave around the walls layout in a 10' X15' space. The star locomotive on my roster is a beautiful *Roco 2-10-2 *German tank. It has all the bells and whistles, including *Dynamic Smoke* and that's where the problem is. In asking guys on Youtube with videos posted of the same locomotive (working properly) I have discovered that they mostly use a Lenz system or other European system with a track voltage around 15-18v My Zepher with I believe 14v at best just can't make the Dynamic Smoke work correctly.

So, I am trying to figure out a way to get the necessary voltage to the tracks. I obviously want to stay as low as I can while getting the smoke to work correctly, so I don't mind a little trial and error. I really don't want to have to buy a Lenz system or other system. I know the NMRA standard is 15v, but that obviously won't cut it. Lastly, I also have a really nice Rapido switcher and they warn against too high of voltage, I need to check that number again because I don't want to fry that loco, but if I need to sell it and just run the Roco, that would be the choice, it is an awesome piece. Here is a YouTube link of it running correctly (another person's loco not mine) 





Hopefully you will understand why I really want it working correctly  
Thank you for any guidance you can give me,

Todd


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## DonR (Oct 18, 2012)

All of the Lenz materials that I found maintain
that the Lenz system conforms to the NMRA
DCC standards. Those standards call for
a track voltage approximately 14 volts,
which you find with your Digitrax DCC system.

You should not attempt to increase the input
voltage of your Digitrax DCC system. You
would damage it. The output voltage is
controlled by the Digitrax circuit design.

There may be a problem with the
smoke unit. Check with the manufacturer
of the loco and/or the mfgr. of it's decoder.

Don


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## jockey31 (3 mo ago)

Correct, the Lenz does coform to NMRA DCC standards, but it also has the ability to allow for adjusments to the track voltage. The Zepher does not. The smoke unit is fine, it works, but the smoke volume is not like in most videos, certainly not as good as the video I posted. I have asked a few people about their videos and they say that they are running Lenz with a track voltage of around 17v
I appreciate the response. The NMRA standard, like most standards/rules have the exception flaw, etc. I don't want to damage anything, but I would like the locomotive to work well. I think in general most smoke units have a hard time below 15v, probably why the BLI products and others made in China for the US market are so weak...but then again the early MTH HO stuff was really good, I just don't remember if I was running analog or dcc back then. Thanks Don.


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## mesenteria (Oct 29, 2015)

I mistakenly ran my Digitrax Super Empire Builder DB150 on O gauge voltage for at least two weeks without realizing it. My HO decoders didn't seem to mind.
HO decoders should be good up to at least 2 amps, some a bit more, like 2.5. Even at 14 volts, that amperage should get through to the decoder unless the decoder is limited to what it can dish out to the various outputs. Maybe your decoder has a resistor on that circuit? I'm betting that it's either voltage or the unit is defective.


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## gregc (Apr 25, 2015)

so what AC track voltage do you measure? i meaure ~14VAC on a club layout using DigitTrak boosters


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## wvgca (Jan 21, 2013)

if you don't have a true rms meter or a rrampmeter to measure the actual DCC voltage, you can use a bridge rectifier and a regular DC volt meter to do the measuring ... add approximately 1.4 volts to the reading you get with the DC meter to accommodate the loss in the bridge rectifier ..


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## mesenteria (Oct 29, 2015)

A reasonably well made and designed meter set on 20v AC should provide a reasonable approximation of the real voltage. Mine measures about 0.5 volts low.


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## jockey31 (3 mo ago)

Thank you all for the info, I believe that my answer is in getting a *Digitrax DB210 *and using it for my track power while letting my Zepher and UT6 remain my throttles. the DB210 can adjust the track voltage beyond the scale selector switch acording to Digitrax by going inside and turning a small potentiometer. This would allow me to put the right amount of voltage to the rails to get the smoke working correctly without going overboard. A much better solution than buying a Lenz or other new system. Now I just have to double check what my other locomotive can handle (Rapido switcher).


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## Lemonhawk (Sep 24, 2013)

I would check the track voltage next to the operating 2-10-2. See if you get a voltage drop when it all started running. You might have a few connections that have some resistance in them such that you are unable to supply the required current. This may be a case where you actually need a lot of feeders to the track, just to keep any stray resistance down. That 2-10-2 may have a larger than normal current draw also, so you might check that also, maybe just the larger current capability of the 210 will work, but I would check all the connections in and to the track anyway.


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## Vincent (Jan 28, 2018)

As a blatantly inexperienced newcomer, may I make a suggestion?

Jockey 31, that video of the smoking European locomotive is magnificent. There is a solid stream of high-rising, sharp-looking smoke.

Are you sure that the video isn't doctored, and that your own locomotive is giving the actual performance?


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## MichaelE (Mar 7, 2018)

jockey31 said:


> Hello, I am a lifetime model railroader, but of course still always learning. Just got back into HO scale and I am using a *Digitrax Zepher* and *UT6 *to run a small home office/man cave around the walls layout in a 10' X15' space. The star locomotive on my roster is a beautiful *Roco 2-10-2 *German tank. It has all the bells and whistles, including *Dynamic Smoke* and that's where the problem is. In asking guys on Youtube with videos posted of the same locomotive (working properly) I have discovered that they mostly use a Lenz system or other European system with a track voltage around 15-18v My Zepher with I believe 14v at best just can't make the Dynamic Smoke work correctly.
> 
> So, I am trying to figure out a way to get the necessary voltage to the tracks. I obviously want to stay as low as I can while getting the smoke to work correctly, so I don't mind a little trial and error. I really don't want to have to buy a Lenz system or other system. I know the NMRA standard is 15v, but that obviously won't cut it. Lastly, I also have a really nice Rapido switcher and they warn against too high of voltage, I need to check that number again because I don't want to fry that loco, but if I need to sell it and just run the Roco, that would be the choice, it is an awesome piece. Here is a YouTube link of it running correctly (another person's loco not mine)
> 
> ...


Roco often uses Zimo decoders in their locomotives. I suspect your Br.95 has a MX645 installed. Check this Zimo manual paying particular attention to pages 33 and 34. These will explain the smoke generator setup and adjustment CVs for the Zimo decoders. 

This will be a mostly trial and error process, and though 20V is indicated in the manual, I suspect this would be for the lone Br.95 on a layout by itself. I don't know of any German system that puts out 20V at the track.

The smoke unit should function properly at a normal NMRA or NEM standard of 14V-16V.

Before you start adjusting CVs, confirm this is a Zimo decoder with the manufacturers code readout on your DCC controller. Failing that, try adjusting the global volume using CV63. If the volume adjusts with this CV, chances are it is a Zimo decoder. However, Roco should have included a decoder pamphlet with the model. They always do.

Zimo DCC Decoder Manual


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## jockey31 (3 mo ago)

Hi Vincent and Michael, the locomotive smoke in the video is not doctored, but the guy is running higher voltage than the NMRA standard and higher than the Digitrax Zepher system. I ended up buying a Digitrax DB210 and the power supply I use with it puts out right at 16v. The locomotive now runs and smokes very similar to the one in the movie above. Roco makes great stuff, I believe this is one of the best smoke/sound systems in HO scale, blows BLI and others away. the difference between 14 (13.6 actual) and near 16v is huge for the smoke output on this engine.


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## MichaelE (Mar 7, 2018)

The PIKO Br.83 and Br.95 are no slouches either in the smoke department.


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