RailPro User Group

RailPro => RailPro Specific Help & Discussion => Topic started by: SWA737 on January 23, 2021, 04:52:45 PM

Title: Engines speed slowing down
Post by: SWA737 on January 23, 2021, 04:52:45 PM

 I’ve had something that has recently started happening to several of my Bachman Diesel engines.  7 of them after running for about 10 minutes have started slowing down until they completely stall but the sound continues to operate normally.  After about a 15 minute shut down, they  start running again perfectly for about another 10 minutes then begin shutting down again.  I have 42 converted engines over to railpro decoders. Some are LM-2S’s and some are LM-3S’s.  All are up-to-date with the latest updates.  I have not run any others to see if more of them are doing that. Has anyone had an issue like this? Possibly decoders overheating?  The caution indicator for low-voltage is coming on up to a couple of minutes prior to this occurring. The track is clean and the wheels also. I do have TCS keep a lives in all of my engines.  The engines are about eight years old of which the past four years have been Railpro decoded.

Title: Re: Engines speed slowing down
Post by: Alan on January 23, 2021, 05:00:55 PM

Sounds like the motors are getting hot and the layout wiring is not sufficiently robust enough to cause the LM to over-current shut down.

Title: Re: Engines speed slowing down
Post by: nodcc4me on January 23, 2021, 05:16:50 PM

If seven engines are doing the same thing, they will all most likely do it. In the event that any permanent damage is occurring I would pick one engine and use it for testing purposes until you figure out what the problem is.


You stated this started recently, so something must have changed. Did you make any wiring changes or additions right before this started? If the modules are overheating you should be able to see that by touching the Info button. If the motors are overheating to the point of shut down the locomotive should feel pretty warm to the touch.

Title: Re: Engines speed slowing down
Post by: SWA737 on January 23, 2021, 06:03:37 PM

 Nothing at all has changed on the wiring. I have a 12 gauge wire buss going around the layout  with drops every 6 feet and four power units separating the four districts from Railpro.  These engines are the less expensive Bachman sound value engines that are several years old now. Could be overheating motors perhaps.

Title: Re: Engines speed slowing down
Post by: nodcc4me on January 23, 2021, 06:25:38 PM

I don’t think the age of the engines is causing the problem. I am running some very old Athearn, Rivarossi and Bachmann engines, but have not had that problem. Did yours start doing this right after you installed the RP modules or were they running OK? What about your newer engines?

Title: Re: Engines speed slowing down
Post by: SWA737 on January 23, 2021, 06:32:00 PM

 I did the railpro conversion about four years ago. This just started recently.  I have a couple of Athearn Genesis engines I will try and see what happens there. Have not run them for a little while. That may tell the story.  I’m assuming if it’s a decoder problem, I would probably get the overload fault or overheat on that perhaps on the HC2?

Title: Re: Engines speed slowing down
Post by: Alan on January 23, 2021, 07:05:52 PM

Pet fur in the mechanism maybe?

Title: Re: Engines speed slowing down
Post by: nodcc4me on January 23, 2021, 07:13:50 PM

That leads me to believe the modules are not the problem, nor the older engines. Check the track voltage with a meter.

Title: Re: Engines speed slowing down
Post by: SWA737 on January 23, 2021, 07:43:04 PM

14.2 volts in all 4 power Districts with 2 different meters. No pets in house. Really a mystery. Thanks for all of the thoughts and suggestions.

Title: Re: Engines speed slowing down
Post by: William Brillinger on January 23, 2021, 07:53:52 PM

Is that track voltage test when the issue is happening? If not, check it then also.

Title: Re: Engines speed slowing down
Post by: SWA737 on January 23, 2021, 08:54:08 PM

 Well gentlemen, I am embarrassed to say I found the problem. In troubleshooting everything I told you all the track was clean. Apparently it was not. My genesis engines ran very poorly as well. I did a sample area of the track and discovered how dirty it was. I had only cleaned it in the fall but, I had  recently done some electrical work in the drop ceiling installing some additional lighting. I guess it was just enough debris falling to create an issue. I’m sorry I wasted everyone’s time helping me  troubleshoot things.
 Lesson learned.  It does seem like after four years operating the Railpro system, it is much more sensitive to electrical issues whether it’s dirty track, dirty wheels or any kind of low-voltage than the conventional DCC systems I have had in the past. I very much love Railpro but, that is one issue I have found that has been a bit of a challenge over the years even with keep alives installed on all of my engines.  I did purchase two nice atlas engines recently and getting ready to convert them over to Railpro. This time I’m going to try Ring engineering keep alive modules and see if  it helps the situation more than the TCS keep alives I have installed  on all of my other engines.
 Again, thanks for everyone’s help. This is a great forum.
Rob Cooper

Title: Re: Engines speed slowing down
Post by: William Brillinger on January 23, 2021, 09:01:48 PM

Glad you found the problem Rob!

Title: Re: Engines speed slowing down
Post by: SWA737 on January 23, 2021, 09:10:57 PM

Thanks Bill

Title: Re: Engines speed slowing down
Post by: nodcc4me on January 23, 2021, 09:12:53 PM

I’m glad you resolved it, but I don’t understand why they took 15 minutes to shut down and then recovered.


Yes, RP is very sensitive to dirty track. My track, running on RP power supply, is spotless, so the engines run well most of the time, but when I run on a DCC layout where the track doesn’t stay as clean, I have had problems.

Title: Re: Engines speed slowing down
Post by: SWA737 on January 23, 2021, 10:24:26 PM

 The only thing I could possibly think about the 15 minute cool down and they’re back up and running is, and I am not an electrical engineer, I know just enough about it to get me in trouble but, I believe as voltage goes down amperage would go up causing things to heat up? I’m sure somebody on this forum can correct me if I’m wrong. That’s my only thought process for why the engines start running again after they’ve been power down for a little bit  after attempting to run over the dirty track and pushing through.

Title: Re: Engines speed slowing down
Post by: Alan on January 24, 2021, 05:14:52 AM

Good to know you resolved the issue.

Your theory may be correct. Not so much the current goes up as the voltage goes down but rather the LM extending the pulse width to compensate. Eventually the LM is running at 100% pulse width making a lot of heat. Although one would think the LM would report over-current just before shutting down. And the sound continuing to play deepens the mystery.

I have a little dollar store hand vacuum the wife was going to throw away because it has so little suction. Turns out to be just the right amount of suction to clean track without sucking up everything around it. With the round brush attachment it only takes 5 minutes to vacuum the whole layout. Because I spend 99% of my time working on the layout and only 1% of the time running trains on it, it has become habit to vacuum before each use.

Title: Re: Engines speed slowing down
Post by: William Brillinger on January 24, 2021, 06:53:10 AM

I'm sure the keep alives are a factor in things continuing to run, as they discharge, things get slower but they should only go for about a minute. In some circumstances when a warning is thrown the loco may need to be removed from power to reset the module. it's possible that the reset happens on it's own after some time elapses - this may be the 15 minutes.

Title: Re: Engines speed slowing down
Post by: G8B4Life on January 24, 2021, 07:29:44 AM

Well thanks to work (which was appreciated!) I got home so late I was so tired I didn't turn the PC on for a day and a half so missed the start and apparent conclusion of this conversation. I know you said you found the problem but I'll reply as I think dirty track/wheels is only one part of the root problem.

To me it also sounds like something is overheating. Addressing the first obvious culprit, the motors, the LM wouldn't report the motor getting hot, it has no sensor for that. All you could do is monitor for the over current warning on the HC. I don't think it's any of the motors overheating.

The second obvious culprit, the LM, has pretty much been ruled out as no warnings applicable to the LM (pretty much the over temp warning) were given.

This leads us to the possible third culprit, the power supply. The symptoms given all point to a failing power supply (or possibly one that is being driven too close to it's maximum rating for too long); this is a sudden onset problem after years of no trouble, it affects 7 locomotives that had no issues that then all experienced the same issue in the same time span, you get the low voltage warning a couple of minutes before everything stops and after about 15 minutes (ample cooling time for the power supply) everything works again (the sound may keep on going because of the keep alive. The sound continuing to play is the only bug in this argument).

What power supply are you using? I'd seriously check it for any signs of failing/failed components, and if you can monitor the voltage and current draw at the power supply. Depending on the type of power supply you have you may even be able to cool it with a fan and see if trains run longer before things shut down.

- Tim

Title: Re: Engines speed slowing down
Post by: SWA737 on January 24, 2021, 07:30:15 AM

 That makes sense on the  module reset Bill and thanks Alan for the thoughts on the vacuuming. My shop vac has too much suction so the one you’re using sounds like a great idea.

Title: Re: Engines speed slowing down
Post by: SWA737 on January 24, 2021, 07:36:24 AM

 Thanks Tim on your reply.  I have four power districts of which all four are using the Ring engineering power supplies. They are not hot  to the touch and when I started having this problem, I was only running a couple of locomotives at a time. I isolated all the staging tracks electrically so no power was going to any of the other  locomotive  keep alives for charging. Don’t think it was any kind of overload on any of those power supplies. I cleaned some track in key areas last night and discovered that was the real problem. A bad overlook on my part.

Title: Re: Engines speed slowing down
Post by: G8B4Life on January 24, 2021, 08:35:44 AM

Well having four separate power supplies would seem to rule a failing / over loaded power supply out as the root problem. That would bring us back to the LM or the motors.

After the loco's stopped how long did the sound continue play for? less than a minute? the whole 15 minutes stopped time? Just wondering.

I find it strange that if dirty wheels and track was the root problem that you could repeat the situation (run 10 minutes, slow, LV warning, stop, wait, run 10 minutes, slow, LV warning, stop, wait ad infinitum) without the run time before the slowing, LV warning and finally stopping getting progressively worse as the wheels etc dirtied up more and more each time.

- Tim

Title: Re: Engines speed slowing down
Post by: SWA737 on January 24, 2021, 08:49:51 AM

 I only left the locomotive on the track for maybe 30 seconds after the motor stopped with the sound going. Don’t know how long the sound would have run.  I will keep you posted on what goes on with it. Will not be able to work on it any today. Thanks for your help Tim.