Howdy folks, new to the forums.
I've recently installed a Loksound Select Micro sound decoder into an On30 Bachman gas mech critter project and am having some strange issues in conjunction with an NCE Power Cab.
The loco will run fine for a short while but suddenly stop recognizing commands and will not reverse, slow or stop. It continues at whatever speed it was moving it prior to the most recent command. Removing it from the track and replacing it sometimes results in it stopping but other times it takes off again. I've reset the decoder several times to no avail.
I've also set CV 29 to disable DC mode, and there are no capacitors remaining on the can motor.
Any ideas?
Is the decoder direct wired to everything, or does it plug into an existing light board?
It's direct. This is a little Davenport gas mech switcher. Light and sound have not been soldered yet, I wanted to have motion sorted first.
How did this locomotive run before the decoder instal? Track and wheels /pickups clean? Plenty of feeders to the tracks? Has a quarter test been done to the layout everywhere? Are you absolutely positive the caps are removed from the motor circuit? Bachmann has been known to hide some where you would not think to look.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
My limited experience with LokSound Select decoders indicates that momentum is set to a very high number as the factory default. Try resetting CVs 3 and 4 to a value of zero and see if that makes any difference.
The loco ran OK before having its stock board and decoder removed, a little rough at low speeds. Both visible capacitors were removed but I'll have another look to make sure I didn't miss any. Not much room to hide them on this one.
I've been testing this on a short section of temporary track that's been well cleaned. the Power Cab goes dark when the track is shorted and the power distribution seems OK.
I don't believe there is any momentum set on the decoder as a default, but I appreciate the suggestion and will investigate. Acceleration and deceleration are pretty immediate and I don't see how that setting could cause the decoder to flat out "ignore" commands.
Sounds like change packets are not being received by the decoder. That could be bad buttons, a bad tether between the paddle and base unit....or the base unit itself has troubles.
How is the decoder connected? Solder or plugged in? Check your solder joints for a cold solder joint. Another thing is the Micro is a .075 amp maximum decoder. If it is running at near capacity all the time it could be a thermal distress thing. I don't think I would try a micro sized decoder in an O scale narrow loco no matter how small it is. There must be some sort of weight that can be be removed for more room or in fact remove the cast weights and substitute lead after the decoder is installed and tested.
Selector, that sounds right to me as well. I'll have an opportunity to test the system with another loco shortly to see whether issues with the Power Cab can be ruled out.
Pete, it hadn't occurred to me that I'd brought a knife to a gun fight and that the decoder just isn't up to the task. Loksound does not provide any recommendations for usage that I have been able to find. This decoder is no larger physically than the stock Bachmann decoder, but of course that says nothing of its capabilities. I'll have to dig around to see if I can find motor specs. For reference, here is a schematic of the loco, if anyone can chime in to say whether its motor is obviously outside the decoder's capabilities or has experience to the contrary, that would be very helpful.
Thanks for the assist!
The stock "Bachmann" decoder for this loco is a 1 amp, and the Loksound is .75.
Its possible that the decoder isn't meeting the needs of the motor, but I did find several kitbashes in which the Loksound Select Micro decoder was used to power this same can motor so it's at least feasible if not ideal.
Can't find a review listing the current draw (there's one in the Garden Railways mag but it's subscriber only content) but I did see in the testing of Tam Valley's wireless DCC that a battery pack of 110 mah LiPo cells runs the thing for nearly an hour - so normal current draw is under 150ma, so the .75A of the Loksound Micro should be plenty adequate for this loco, unless you are making a habit of jamming the gears so the motor can't turn.
It may be related to packet timeout. Some systems don;t send a DCC packet to an address unless something has changed. Easy to test this out - constantly click the throttle wheel up and down, just one click in each direction, constantly, while running the loco around. or constantly (every few seconds) sound the horn - just so there's continual activity, instead of sitting back and just watching it run. If it keeps responsing and doesn't have this issue, then this is indeed what's happening. If it still dies on that same section of the layout (horn stops honking even though you keep pressing the button) then it's got to be something with feeders and power connections eating the signal. You mention plenty of feeders - how are they connected back to the system, what size wire did you use for the bus? How long a run of wire is this? NCE seems prone to malformed signals on long bus runs if a 'snubber' circuit is not connected tot he far end of the bus wire.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Randy I was looking for just this kind of comparative data, thanks. I also just discovered that Soundtraxx recommends their micro .75A Tsunami decoder for several of the small can motor Bachmann On30 locos, including the Climax, Baldwin, Porter, and the little 0-4-0 Davenport I'm using to fab this critter. So I don't think current capacity is a problem.
I've just been reminded that the NCE Power Cab has a built in ammeter, so I will know soon exactly how much load this loco is drawing to confirm that the decoder can handle it or no. I'll also try your method of sending repetitive commands.
In any case, the decoder will be replaced. I just received a prompt response from ESU advising me to return the decoder for immediate replacement. Very pleased with their customer service thus far, I suspect that I just happened to get a faulty unit. Hope it works out, I'm eager to get back to modeling!
Just don't forget to let us know if that solves the problem or not ... I have a very similar problem with a new locomotive.
www.oakhurstrailroad.com
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Yeah, there's nothing worse than a troubleshooting thread without closure.
For the record, the ammeter on my NCE Power Cab tells me that this little unit has a pretty small load... the highest value I could get while stalling it was .35 amps, and that was far above the norm which was .1 - .15 on average. Bear in mind that this was an install without the loco's LED light or speaker connected, so I can't speak to the draw with those elements in play.
In short I guesstimate that the Loksound Select Micro would be just fine for the project. But since my particular decoder is problematic and ESU has very graciously offered to replace it with the larger 1.1A capable decoder at my request (and I can make room for it) I will go that route. I don't wish to stray from forum rules but would be amiss if I didn't make it known that ESU had been really great in tracking down this problem... I've had mails from both the GM and his assistant who are eager to correct the issue. This level of customer service is well appreciated.
Thanks to everyone who contributed, I learned a lot about motor load and troubleshooting these chips. If I run into further troubles I'll post them here, otherwise assume that all is well.
*doffs his hat*