DCC Layout Electrical Issues

[tappertrainman]

Hi All,

I'm hoping the wizards here can help with some advice regarding my N-scale layout.  See below for a video of the problem in action (plus cute kid commentary!)

This happens with all of my locomotives, but at different places on the layout.  This FP45 is the best, but still stops almost every loop around the layout, other locos are worse and stop every couple feet.  Some stops are near turnouts, but not always, and it doesn't happen in the same place every time.  I don't normally run trains this fast, but this was just for example, the problem is somewhat worse the slower a train is running.  The track has been cleaned and cleaned and cleaned again, and this train runs with a track-cleaning car (behind the loco).  There are feeders every 2-3 feet and there is no measurable voltage drop.  I also tested the voltage away from where the trains stop, and the juice remains flowing throughout.  It's an older NCE DCC PowerCab with no known firmware upgrades, but the problem also occurs with another newer DCC system.  You can also see from the video that the trains start themselves back up, I did not touch the train OR the throttle at all during the video.  Any one have any ideas what is going on??

[rodsup9000]

  Dirty wheels on the locomotives and or dirty pickup axle points on the trucks

[peteski]

You mentioned cleaning the track, but just as important is cleaning the loco wheels, and any other electrical contacts in the locomotives will also need cleaning from time to time. The wheels need to be cleaned often.

That would be a good place to start, before getting into digital troubleshooting.

[Maletrain]

If it restarts without any thing being done to the electrical or physical situation, not clear to me how it can be simply poor electrical contact due to dirt on wheels, wipers, or whatever.  The video shows 2 stops as the train crosses turnouts, so I am thinking short circuits on the turnouts.

It almost looks like the power supply to the Power Cab is shutting down.  So, I'll ask this: When the train stops, what is the Power Cab showing?  Does its display go blank?  If not, please set it to show current and tell us what the current is when the train is running and when it has done one of these stops.

[peteski]

If it restarts without any thing being done to the electrical or physical situation, not clear to me how it can be simply poor electrical contact due to dirt on wheels, wipers, or whatever.  The video shows 2 stops as the train crosses turnouts, so I am thinking short circuits on the turnouts.

It almost looks like the power supply to the Power Cab is shutting down.  So, I'll ask this: When the train stops, what is the Power Cab showing?  Does its display go blank?  If not, please set it to show current and tell us what the current is when the train is running and when it has done one of these stops.

Clean wheels are important, but you do have a point.  If he was to run more than one loco on the layout, and both stopped and started at the same time, that would also indicate a problem with the DCC system.  What is puzzling is that he mentioned that the problem is even more severs when the train runs slower (draws less current), and that it acts the same when using another (unnamed) DCC system.  That would seem to indicate that the decoder might be causing the problem.  Again, having another loco on the layout would be helpful in troubleshooting.

[Maletrain]

We are assuming that the Power Cab (or the other unnamed DCC system) is being connected directly to the track, with no intervening circuit breakers or autoreversers.

The OP needs to tell us if that is true, or not.

[peteski]

We are assuming that the Power Cab (or the other unnamed DCC system) is being connected directly to the track, with no intervening circuit breakers or autoreversers.

The OP needs to tell us if that is true, or not.

It appears to be a simple single-block layout, but yes, we are still lacking more detailed information about his setup.

[Steveruger45]

Yes, more info, but it does look to me like a power shut down and reset.  You said same occurs on other dcc system.
Are you using the same power supply?

[Maletrain]

I doubt he is using the same power supply for another DCC system that he is using for an early version Power Cab.  The Power Cab uses a wall wart, and the early ones had wall warts that would shut down at something around 1.3 amps, despite the Power Cab itself being rated at 2 amps.

But, the nice thing about the Power Cab is that the display can be set to read amps.  So, we should be able to get some decent info about what is really happening.

[tappertrainman]

If it restarts without any thing being done to the electrical or physical situation, not clear to me how it can be simply poor electrical contact due to dirt on wheels, wipers, or whatever.  The video shows 2 stops as the train crosses turnouts, so I am thinking short circuits on the turnouts.

It almost looks like the power supply to the Power Cab is shutting down.  So, I'll ask this: When the train stops, what is the Power Cab showing?  Does its display go blank?  If not, please set it to show current and tell us what the current is when the train is running and when it has done one of these stops.

Hi all, thank you so much for the discussion and advice!

I have cleaned the loco wheels, but not the axle points, I will try that soon.

To my recollection the PowerCab display stays on, but I don't remember what the amp meter shows.

The other DCC system is a PIKO SmartControl, a licensed version of the ESU SmartControl.  I was using each system's respective power supply.

There is only one block, since it's DCC, and there are no other circuit breakers or autoreversers.  One of my thoughts had been to purchase FrogJuicers but I have not done that yet, and like some have noticed it doesn't explain why the trains start themselves back up.

I will try to reply back with some more info tonight about what the amp meter on the PowerCab shows.  I will also try to have another loco on the layout and report back whether the sound dies on it when the other stops (I seem to remember it doesn't, but I want to be sure).

Thanks again all!

James

[peteski]

I'm leaning more towards the decoder in that loco (not the DCC command station) having problems.  But any additional inifo will be helpful for the final diagnosis.

[Maletrain]

I'm leaning more towards the decoder in that loco (not the DCC command station) having problems.  But any additional inifo will be helpful for the final diagnosis.

The OP said it happens with all of his locos, that is why I am not suspecting the decoders. 

What I am suspecting is his turnouts.  He says it doesn't always happen at turnouts, but it might still happen when his locos are past the turnouts if some of his cars have metal wheels and they are sometimes shorting on frogs or something else.

[nickelplate759]

...
But, the nice thing about the Power Cab is that the display can be set to read amps.  So, we should be able to get some decent info about what is really happening.

I did not know this about the Power Cab, and had been wanting a DCC ammeter, AND already have a Power Cab.  Works like a charm - thanks for mentioning this feature!

[RBrodzinsky]

Another set of questions to consider: where are the feeders on the layout? How many and distance between?

[peteski]

The OP said it happens with all of his locos, that is why I am not suspecting the decoders. 

My attention span, and reading comprehension are getting shorted and shorter.