I have purchased a used walthers proto 2000 series sw9/1200 locomotive claimed to be operational by the previous owner a few days ago, but when I tested the loco to see if it ran, it briefly moved at a slow speed, but then the power pack i was using to test the loco turned off, apparently for a short circuit. This happened while both going forward and backward and for both powerpacks i used (kato SX and S). I opened the loco up and took a look inside but it seemed just fine, but I noticed that a DCC digitrax decoder was installed. I don't have a DCC system. Is the decoder causing this problem? What should I do to make this loco run properly? Thank you for reading my post.
Your first few posts are moderated, but if you stick around that will clear up. I don't run DCC either, so it's a bit out of my wheelhouse, but from what I do know about it I do believe that it may be possible for the decoder to draw too much power from a regular DC power pack. I may be wrong though, so maybe someone with more knowledge than myself will chime in. Is it still possible to contact the previous owner? If so, maybe they could help out. Another thought would be to contact Walthers and see if they can help. Here's a link to their contact page: https://www.walthers.com/contact-us
If the decoder is an 8-pin plug in variety, just remove the decoder and install a dummy plug in the socket for straight DC operation. If you don't have one you can also use some small gauge wire to jump together pins 1-2-8 and 4-5-6 of the 8-pin plug. As illustrated in this picture:
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
The Kato powerpacks are pretty small, it's possible it's not a short but just overloading it. Plus, what could be happening is that the decoder is set to allow a very low top speed.
Decoders now are basically all "dual mode", the engine with the decoder runs the same on DC or DCC - unless it's a sound decoder, that's a different issue. So an engine that runs say 60 scale MPH at top power in DC will run about 60 scale MPH at top power in DCC. However, if you want to, you can reduce the top speed in DCC so the engine maybe only goes 20 MPH at top power. (This way you can slow down a fast engine so it can run together with a slower engine.)
Although it's set in the DCC decoder, the top speed setting will affect DC operation too. So if the previous owner set the engine to run really slowly, it may be before it gets enough DC power to really start running, your power pack is overloading.
If you know someone who runs DCC, or perhaps have a local hobby shop you could visit, it only would take a minute or two to change the DCC settings. A hobby shop might even have a dummy plug for you, if you choose to remove the decoder. But if you get the settings changed, it may be the engine will work OK with the decoder left in the engine.
thank you all for your great help! I'm planning on getting a dcc controller to test the loco. thanks alot!