I have just installed a NCE DASR decoder in a Genesis SD75 loco. All went very well, they are quite simple to fit and wire in. All the lights work as required. It was programmed using a Digitrax Zypher and a programming track to do the initial set up and a DT400 to do the finer adjustments on the main line.
However, when I try to accelerate, the loco starts off O.K.runs for about 15 in. then stops and starts, runs for another 15in. or so and repeats continuously.
I have programmed CV3 with 50 and CV4 with 90 . I have tried some of my other locos that are fitted with Digitrax decoders with similar CV settings and they perform O.K. I have tried varying the values in both CV3 and 4 but the response is the same. I tried the direct throttle approach by cancelling both CV3 and 4 and it performs correctly.
I would be interested to know if anyone has an idea as to what the cause might be or may have had a similar problem. Any suggestions would be welcome. CPPedler
Ok Does The decoder have anything that when it gets over heated it shuts off? Because thats what it sounds like tis dooing if it will work for so long stop and then start working again, it could be over heating. Not sure how you would fix that, it should really do that though because loco’s are meant to be ran for more then 15 mins, Restore too Factory DEfault see how it reacts.
If that doesnt work if you happen to have another decoder that will work for thsi loco put a new one in see what happens. If it still happens we will know it is your loco if it doesnt we know its your decoder and it could be defevtive or over heating.
Could very well be a heat problem, but that would depend on the load on the motor. The decoder may get warm over time, for sure, but you’d think the variable would be the heat output from the motor.
It would be useful to record the running time to see if it shortens with load. Otherwise, it could also be an intermittent breakage in contact at a solder if it is heating up. I take it that this happens at random places on the track, and not in one area…so it’s not dirty track?
I was rereading your post and i noticed you said it was a genisis sd75 i too own a gensis sd75 a SF, installed a digitrax in it and never had any problems and tended too get hot someimtes but that was after a good bit of running and it never stoped. So it has too be the Decoder or how the decoder was set up if it is the heat thats doing it. Like selector said run some load tests see if running it solo willl improve its run time over having it fully loaded
Also when the engine turns of do all the other loco’s on the track stop working aswell because if that loco and others dont run at same time, it could be you are shorting out somwhere or the dcc system itself is over heating. you could just have one to many loco’s requesting power.
It does sound like an over heating or a short of some sort!
Not being at all familiar with the decoder you have installed, I can’t really address the problem there…But beyond the decoder being the problem, here may be a few things to look into:
Do you have an automatic re-setting circuit breaker anywhere in the system? It could just be doing what it’s designed for. But then that still makes for a problem (too high of a amp draw, binding drive…something) with the engine. Run it with the shell off and see if you can detect anything odd.
When this engine shuts down, does the entire pike shut down, or just this one engine?
When you are running the engine and it shuts down, is the decoder or the motor real warm to the touch?
Just a few thoughts…
Thanks guys for all of your input into this. I had cleaned the track a couple of days ago but I have now done it again.
I had another identical decoder to fit into another identical loco, so I did that this morning and programmed in the same CV’s and guess what?? Same problem. They both run fine until I program in CV3 and 4. I don’t think that it is a short because if I run them about 3 feet apart, they only stop one at a time and neither of them seem to get warm at all.
These are the only Genesis loco’s that I have and I was wondering if the wire connections at the trucks might be the problem, I will remove the plastic sideframes to see how the wires are attached to the pick-up bars, they might be clamped and not soldered and cause a loss of power momentarily. I can’t believe that the decoders are both faulty. Incidentally both of the loco’s are brand new and had not been run until now.
I’ve had enough today and will go back to it tomorrow, with fresh zeal. It’s probably something quite simple in the end. Thanks again CPPedler