What would cause a DCC equipped locomotive to occasionally stall, while the sound continues? I.e., The locomotive moves over the layout and just stalls. Dirty track? Maybe but this is after several hours of operation with track cleaning cars in the consist. Most if not all rail joiners are soldered. It doesn't repeat the stall at the same locations. Sometimes we are able to activate the horn, bell or lights and at other times we are not. I took a meter and went over the tracks. Set to AC it reads 15 volts, everywhere on the layout, including the spots the loco stalled. The only dead spots I found...the frog's in older Custom Atlas Switches. Wire drops are approximately every six linear running feet, apart. Wire used is 14 gauge to the wire drops. Wire drops are 18 gauge. Take a shot at this, any ideas are welcome. Me thinks we need some engineer types.
I suspect there's some type of contact interruption between the decoder and the motor. It's obvious that the decoder is getting power, and I suspect the locomotive's wheelbase is long enough to span the dead spots that you've found in the turnouts. I suggest you pull off the shell and take a look at how the motor gets its power from the decoder and troubleshoot from there. I think this type of contact problem can be fairly common with decoders that depend upon a set of contacts pressing against similar contacts on the motor, as in many n-scale installations. Also take the opportunity to ensure there are no short circuites between the motor contacts and the loco frame. If there is even a chance of a short, the decoder will fry, so be sure to put a bit of tape (preferably Kapton tape) on the frame below any motor contacts. If on the other hand, this is a hard-wired installation, you may have some type of motor problem. Hope this helps. Let us know what you find out.
Paul, Thanks for the response. We had a problem with a steam locomotive and it was the plug in's. Checking the physical attributes of other locomotives as we move forward. Several of the locomotives that perform this awkward stall of a dance are factory DCC installed decoders. I don't think we expected this kind of a problem from them. Also, looking at handheld's to make sure they are working properly. No way that I know of to test them.
I don't run sound, but this happens to me also. Train running and then suddenly stops. Just for a second or so then resumes speed. Sometimes its one locomotive, sometimes its two seperate trains at the same time. Decoders are a mix of Digitrax and stock Bachmann decoders. Old MRC commamd 2000. Its not because its overloading the system, couldn't possibly be drawing more than 1 amp with two trains running. Its just strange, I have no idea :question: ....Mike
I should mention here we are working with MRC Prodigy Advance. Digitrax, MRC, Bachmann and other decoders.There are three layouts in the neighborhood that operate with such. Question? How do you know when the system has shorted out? Does the hand held indicator do something crazy as in some sort of anomaly. It's possible we have a intermittent short in the system. Looking at such as we re-inspect the wiring for the umpteenth time. Just doing a search to see if this topic has come up before. Noted, Dave sounded off about a problem that sounds all to familiar with the above: http://www.trainboard.com/grapevine...co-with-Digittrax-decoder&p=930318#post930318
I and members of my club have this problem with stopping occasionally. I correct the problem by clearing the command stations memory (Digitrax). If you don't dispatch loco's, and then reselect the same loco the command station thinks it is running two locos with the same address. The command station sends out information packets to the running locos. It keeps the selected loco running with the last input from the throttle, but it then sends out another packet to the loco with the info for the loco from the previous session which may be at speed step 0 stopping the operating loco for a few seconds. Then the command station renews the packet for the running loco and it resumes speed again. This keeps repeating until you clear the command stations memory, or properly dispatch the loco.
Hi All, I have had this problem with my Digitrax system. My issue was caused by having two throttles set to the same address (locomotive). Gary
If the sounds persist when the locomotive stalls, it isn't a short. If you do have a short, you should get an audible beep or something...at least, the Digitrax systems do that. However, a short detection circuit should cut off power to the rails, so if the fault on the tracks goes undetected/uncorrected by you, the DCC system should persist in the alerts and in keeping power from the rails. The fact that you still have sound after a possible on-board keep-alive capacitor has given up its stored power means the rails still have power. Ergo, your DCC system is not shutting off track power, and my bet would be that it has not detected a short. What does that leave? If the sounds persist and the motive component seems to quit, you have either a defective decoder, an intermittent connection between motor and decoder, or a faulty/needy DCC system that is telling the locomotive to stop and then to resume motion...which hardly makes much sense unless you have conflicting information packets being sent alternately to the decoder where the system thinks two such addresses are active...as retsignalmtr suggests. My bet is that you have an iffy solder or a broken one, or a connector that has corrroded or simply failed/slipped free and only the spring-like tension of the wire keeps the contact with the post.
Coverton, Sounds like the same types of problems we have with Analog DC. Any cold solder joints can cause a locomotive to stall on a section of track. That's true of a rail joiner that makes intermittent contact. Once the metal is pushed together so it touches and is soldered....problem solved. Just not in this case. There are plenty of problems on the layout. Several of us will be teaming up to trouble shoot and correct the problems. Kind of dealing with a difficult situation.
We believe this has been a problem as demonstrated by the owner playing a trick on us. It is what it is.
Rick, On the Prodigy Advance 2, I get a quick low sounding chirp, and the hand helds display "SVDA". It stays that way until the short is cleared. I usually do a quick shut down and remove the derailment. If you don't get SDVA, I believe the system doesn't recognize your problem as a short.
I had a Spectrum decapod that did this, and it turned out to be a problem with the motor brush springs. They were loose enough the brushes would occasionally lose contact and the motor would stop.
