I have a Digitrax SDH164 sound decoder in my Rivarossi Challenger and it was running fine until a week ago. I don't know why it stopped but I have tried to find a loose connection or ?? and nothing works. It did move the engine a couple of inches the other day and then nothing. I felt the decoder and it was warm/hot but don't know how hot is would be normally, so I can't judge it as being overheated. I am doing all of this with the boiler off so I can see the decoder and wires. I put it on my programming track with DecoderPro and it says it can't find a decoder. Should I consider it fried or is there another way to find out if the decoder is really fried or just a loose/weak connection somewhere? All my connections are soldered and covered with shrink tube.
Thanks,
-Bob
Life is what happens while you are making other plans!
Did you test for current draw before installing the decoder? From your description, it sounds like the mechanism might be binding and causing excessive current draw, thereby overloading and frying the decoder.
The only way to know for sure is to put a new motor control decoder into it if you can't program or reset the sound decoder and see if it will run.
Then start looking for the mechanical cause of the overload -- pulling too heavy a train -- pulling too heavy a train upgrade -- a binding mechanism, etc.
Smell the decoder, if it has a burnt smell you have let the smoke out.
Cuda Ken
I hate Rust
cacole Then start looking for the mechanical cause of the overload -- pulling too heavy a train -- pulling too heavy a train upgrade -- a binding mechanism, etc.
Seriously? Pulling too heavy a train can fry a decoder?
Rich
Alton Junction
Depends on the stall current. If you have a motor that draws a lot of power it will work fine until it has to do a lot of work or stalls, then it will draw max.
To test set the loco up as straight DC with no decoder. Then put a current meter in series with a DC power supply. Hold the loco and increase the throttle. Hold the loco still and read the current. The reading should not be at the maximum of the motor current for the decoder and obviously not higher.
According to the installation instructions the SDH164 has a stall current of 1 amp.
Springfield PA
The newer can motor Rivarossi locos should be fine, but if this is one of the older ones, definitely too much current draw for that decoder. Tsunamis are also 1amp, so no help there. Luckily it's a big loco - so you can use a regualr 1.5-2 amp stall HO motor only decoder to drive the motor plus a sound decoder for the sounds. Plenty of room to fit it all in there AND use a massive speaker.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
The engine is the newer with can motor and should not be overloading the decoder. I have been runnning the engine for several months without any rolling stock behind it so I haven't overloaded it that way. As for binding mechanism, I haven't had any problems with binding. I guess I will remove the decoder and try another decoder or just run on DC to see if it runs without a decoder. I have a NCE decoder tester which I will try to hook up to the decoder and see if it shows anything. Thanks for all the suggestions.
farrellaa I have a NCE decoder tester which I will try to hook up to the decoder and see if it shows anything.
I have a NCE decoder tester which I will try to hook up to the decoder and see if it shows anything.
That ought to tell you if the decoder is any good or not.
Hi Farrellaa,
Could you post your findings when they are available after your testing? I use the same decoders and am interested in understanding the outcome.
Kind regards
I will post my findings as soon as I get to test the decoder. Having back problems and can't work on layout/trains for a few days. Thanks
Well, I guess it is fried! I hooked up my NCE decoder tester and got no response. I tried the Digitrax program track and it indicated there was no response from the decoder. I removed the decoder and it was very hot, so hot it melted a hole through the blue plastic wrap exposing a smooth metalic surface that was very hot. I rewired it and ran it back on straight DC and it runs without any binding although the top speed is not very high. I think it ran faster before I went to DCC but can't really know for sure. I checked all the linkages and drivers and don't see any binding. I oiled all the linkages/valve gear and driver axles as well as the motor bearings. It still runs very smooth but just not very fast; I would guess at a top speed (scale wise) at about 40-50 mph. I haven't tried to check the amperage draw at a stall but that is the next step. I MUST know how much (amps) my next decoder has to be rated at.
Bob,
Thanks for the update.
Rest assured that you are not the first, nor will you be the last, to fry a decoder.
Welcome to the club!
It doesn't mean that you did anything wrong. Sometimes it just happens.
I contacted Digitrax as this decoder is only 6 months old and they said to return it with their 'Return Form' and since I can't find the receipt, I enclosed a check for $17.00 to cover the cost of repair/replacement??? Will wait and see. If they are as good as Bachmann I should have replacement decoder in a few weeks. In the meantime I will run it on DC. thanks again for all your input.
This is why you save receipts, but keep them hidden from SWMBO, lest she find out exactly how much you REALLY spend on trains. With a receipt it would have been a free repair/replacement - Digitrax now does what TCS does, and even if you fry it through installing it wrong, the first fix is free.
I ususally save all my reciepts for decoders, locos and electronic components and know I have the one for this decoder, just can't locate in the 'filing system' in my train room. I don't know if I have a SWMBO but it sounds like I might. I don't offer too much data when it comes to what things cost on my train empire. I was told that $80 was a lot of money for one locomotive!
Thank you for following up with your findings farrellaa. Much appreciated here.
farrellaa I was told that $80 was a lot of money for one locomotive!
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
jeffrey-wimberly farrellaa: I was told that $80 was a lot of money for one locomotive! Those who think $80 is a LOT of money for a loco haven't looked at a Walthers sales flyer lately. Many of the ones I see there are $200 and up.
farrellaa: I was told that $80 was a lot of money for one locomotive!
I would agree 100% wiith you on that. However, that comment was from my wife who thinks most of my hobby items are 'way too expensive' and she never looked at a Walthers flyer. She also thinks $20 is a lot to pay for a womans blouse, which is fine with me!.
BTW my decoder was replaced by Digitrax and they indicated that it was fried. I haven't installed the new one yet. I want to do a stall test to see what amperage it pulls.
Smart choice. I did that with my two SDP40F's before putting Digitrax DZ125 decoders in them. Both have Athearn bodies. The lead unit has an Athearn drive cobbled together from an Athearn blue box SDP40F and an Athearn AC4400. The second unit has a Proto 2000 drive from an old E6 which incidentally uses an Athearn motor. The stall current was well within the limits of the decoders. Either loco on it's own could pull a long a 22 car train but the two of them together have phenomenal pulling power.
farrellaa I ususally save all my reciepts for decoders, locos and electronic components and know I have the one for this decoder, just can't locate in the 'filing system' in my train room. I don't know if I have a SWMBO but it sounds like I might. I don't offer too much data when it comes to what things cost on my train empire. I was told that $80 was a lot of money for one locomotive! -Bob
SWMBO
She Who Must Be Obeyed.
Blue Flamer.