New DCC Sound Loco not working

[Bywater Railroad]

:confused: I posted this in the general discussing before but I am still at a loss.:confused:

I bought a Walthers Proto 2000 E7-A unit with dcc sound last December. Ran great the two months I had it. I derailed one day, in mid Feb. then suddenly the sound garbled and with in 5 minutes of that, the engine stopped, nerver to run again. I talked with Walthers, I sent it in and they sent a new one. The replacement was running fine since March, then suddenly, just like the first one, derailed and, the sound garbled and then went silent. Only this time the engine still ran for a while with no sound. Sometimes it would start up with a small bite of sound then run silent. Now it will not even run. I am using no DC locos on the layout and all other DCC units are running fine. I use the NCE Power Cab. I have feeders to a buss for the rails. I have other DCC sound and non sound run with no trouble. Any thoughts. :confused:

[NIMT]

I would say you cooked it again.:eek:
Try resetting the decoder, see if it will restore function, If it's still under warranty send it back again!;)
Can you take a coin and short out the rails and get an immediate shutdown without a spark or overload?:confused:
You usually only hear of people frying their decoders if their DCC controller doesn't shut down properly and causes a spike in the power.
I can get mine to shut down within milliseconds with no spike.
You can test it with an 1 or 2 automotive bulbs and when you short the rails see if they get brighter before shutdown, same on startup.:cool:

[Bywater Railroad]

So with DCC every time an engine derails it will short out and cook the decoder? How is that? I had other engines derail and the Power Cab system reboots itself. Is it correct that you think the Power Cab was not shutting down and rebooting when this engine derials and shorts? How can this be avoided? Thanks for the help.

[NIMT]

No your power cab should not cook any decoder, and yes I'm questioning if the NCE is shutting down properly. It's super rare but I have seen it. If it's not shutting down it might just need a update to correct it.
I have a digitrax system and I push 32amps to the rails if my system didn't shut down super fast I would completely fry or melt a derailed piece of equipment in a snap! There are some power distribution units that would help too!
Test it and then you'll know if you need to take further action or if it's just a flaky decoder!;)