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Question is what should my track voltage be?  Running 4 Mth Diesal engines and on 1 Atlas diesal on my layout with 3 power districts using digitrax DCS 240, DCS 210 and DB 200 .  running the whole layout with Railroad & co. Version 9 . My track voltage is 17.v   is that enough?  Everything seems to work well until all the trains end up in the same power district and cross the reversing sections. IT will short out when the digitrax AR-1 trips.  Wondering if I do not have enough power? I have trimmed the Boosters up to 24V. and they seem to run better. But my boosters keep going back to 17v when powered off.

Any Thoughts?

Thanks

Scott 

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Voltage is not the problem, amperage is.   

You have answered your own question, when you have all the locos in the same distrit, it shorts out.   IE you are drawing more amps than the Booster for that section provides.   

Now you mention a reversing section, and that implies a quick short to trigger the AR1.    Another possiblity is that the booster breaker/short detection is faster than the AR1.    So when you cross the reversing gap, the short shuts down the systme before the AR1 can reverse polarity.    You could try setting the timeing for the breaker on the booster to be slower than the AR1, or set the AR1 to be faster than the booster.

I have never heard oif RR Company VER. 9 and how it relates to DCC.    Is it something that is fully NMRA DCC compatible, or something sort of works with it in most cases, as some decoders out there.

Hi Scott,

With my Digitrax system similar to yours (just older), I ran up to six dual-motor Atlas and MTH locos in the same power districts with no issues.  I had the track power set to "HO" - about 15V and used 8A boosters. The power districts were subdivided with PSXs and one PSX-AR for an auto-reversing section.

These "China-drive" locos typically draw less then 1 Amp each pulling up to 20 x 1lb cars on level track. So I'd be surprised if the issue is current draw or track Voltage. I actually use HO decoders in them now on my ESU CabControl system with no issues. 

So I would be looking at the auto-reversing setup for the issues first.  Can you give us a simple diagram of the setup? That may help. For example, if a long train can span the entire A-R section that could be an issue. If two trains can cross the A-R section gaps at the same time that could also. If the A-R section is next to different booster districts at each end, or to more AR-1s, so could that.  If the boosters have a faster reaction time than the AR-1 that's another factor.  And if you have Frog Juicers or similar they can also be a factor.

There's a reaction time hierarchy to short circuits (over-current) to make it all work.  Devices inside a power district need to be fastest e.g Frog juicers. Then auto reversers and power district devices e.g. AR-1, PSX, PSX-AR, and the slowest reaction time needs to be at the booster.  

The AR-1 is an old design these days and not the fastest.  So you likely need to set your boosters to slower reaction time.

One last thing to look at: With Digitrax you must have a large booster common wire e.g. 14GA between each booster and the command station/booster connections. Do not connect this wire to house ground though! This ensures sufficient current can flow at a short circuit to trigger these devices. Without it, the only path for this current is through the tiny Loconet wires. 

HTH

 

Pete

Thanks for the reply! When you mentioned common ground between boosters did you use Pin 4 on the boosters between them all? In the diagram both reversing tracks are isolated Blocks on the layout through a BDL168 each on it's own Zone.  Frog juicers on the switches before and after the reverse section.  Come to think of it one time the short accurred there was a train on one of the switches on outside loop and one train on the double gaps at reversing section.  Don't know if that is an issue or not. 

Thanks

Scott

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  • Reversing section

Jim: Good to know, thanks. I think we'll need fastest = Frog Juicer, medium = AR-1, slowest = booster in this case.  Frog Juicers are pretty quick so with the AR-1 and boosters being adjustable we should be OK.

Scott:  Thanks for the diagram. Presumably you have 1 x AR-1 on each main line? Would any train be long enough to span both ends of the whole reverse loop? If not, can you extend the AR-1 coverage to the whole reverse loop without messing up your detection?  Might be better to have the Frog Juicer at the spur and the spur itself inside "AR world" (unless there's more to the spur than you showed)! 

Regarding the Digitrax booster common, on my older Digitrax boosters it was connected to the "ground" screw terminal on the front of each booster, usually in the middle of the big connector that's also used for power in, track power etc. There's a lot of info online about this. Many qualified EEs seem to feel strongly that Digitrax calling it a "ground" not a "common", and  recommending this wire also be connected to house ground at the command station is a potentially fatal error. The Digitrax user group is a good place to start: https://groups.io/g/Digitrax-Users/topics   

Last edited by Pete M

I am pretty sure that you DO NOT want to connect that wire to the house ground.   A friend of mine who is a master electrician read "ground" in the instructions for his NCE system so he did just that and destroyed a few boosters!   I would think same is true for digitrax, it is not an "earth ground" but just creating a ground plane between the boosters.

Thanks for all the replies.  I've made sure I have the common ground between all boosters. I did find the power to the Ar -1 wire loose so I tightened back up. Turned the Ar-1 sensitivity up and down to try and find the right setting. Sometimes it works sometimes not.  Now I have had the booster shut down when an engine crosses the power district which I have not been having.  Just not sure what I have going on. This booster is A DB 200+ and set in the run mode.  Is it possible it would try to auto reverse on it's own in this setting? Looks like I've got a lot more research and trouble shooting to do.  I joined the digitraxs groups so I hope there will be some insight there to.

Thanks

Scott

I wouldn't set a booster adjoining an AR-1 district to reversing because they will get into a phase flip battle. Best to have any auto reversing section adjoin a non-reversing power district.  

Sounds like you're closing in on the solution though.     I think you need the AR-1s to trip slower than the Frog Juicers, and the booster to trip the slowest of all.  For Digitrax Command Stations you can set the trip to slow with Ops Switch 18.

http://www.digitrax.com/tsd/KB...ion-option-switches/

That would be about 0.5 seconds.  That's slower than the Frog Juicers for sure, and hopefully the AR-1s range of reaction time adjustment allows them to be set in between the two.  After some research I'm not sure if you can actually do that with Digitrax stand-alone boosters though. 

So maybe you could power the district(s) adjoining the AR-1 districts from your command station. Set the command station to 0.5 seconds.  Then run trains over the AR-1 gaps and Frog Juicers while adjusting the AR-1 knobs.Hopefully you can find a setting where the Frog Juicer always trips first when just the frog gaps are shorted, plus when crossing the AR-1 gaps the AR-1 always trips before the command station.     

Hopefully not too many permutations to try...    

Last edited by Pete M

Thought Id post an update on my question and what I've found.  After looking back over my wiring I did discover that the common ground on the DB200+ booster and the green sync wire were loose. Tightened them up and seems to have resolve the issue on the AR-1.  But the Strange thing I discovered is that the DB200+ was out of phase with the the other boosters when I tightened every thing up. I reversed the wiring (RailA and RailB) and everything is back in phase.  Ran my trains the rest of the day with no issues.  Went back to the trains Friday and put the DB200+ on a  PS2012 Power source.  Much to my surprise the booster was out of phase again?  Is it possible that this Booster since it can be configured an auto reversing booster is somehow tripping the phase on me even though it is in the run mode not the auto reverse mode? I switch Rail A and B back and everything goes back to working. This booster is supplying the power to the reversing section through the AR-1 as well as the Yard in my sketch.  Puzzled as to how and why the Phase would change?

Thanks

Scott

 

 

 

 

 

 

 

 

 

Hi Scott, glad to hear you're finding and fixing issues.   

Some Digitrax boosters can flip phase if they power up at exactly the same time as the command station. I've read they need Loconet sync first to decide which phase to adopt.  The cure is, once you have all boosters at the correct phase, always power up your command station first, wait a few seconds and then power up your boosters. 

I had that same issue and the cure worked for me.  

You do need to make sure that booster isn't set to Auto-reverse though as it will fight the AR-1.  But I don't think you have that issue as your trains wouldn't make it through the booster>AR-1 gaps.

Last edited by Pete M

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