Hi. I'd appreciate some help to ensure I don't have this problem again. I installed a TCS drop in decoder ASD4, in an Atlas GP9. The engine ran fine in DC. I checked the loco for shorts after removing the DC lightboard. No issues. I dropped in the decoder, check for shorts, no problem there, programmed it quickly on my NCE Power Pro test track. I put the loco on mainline track and it ran quite quickly. I removed the loco and checked it out. No visible issues. I put the loco back on the programming track. No problems, it programmed quickly. I again tested for shorts, it was fine. I put the loco back on the mainline, applied some power and you guessed it, puff of smoke and dead on the track. I have installed a dozen of these decoders, so this isn't a first time installation gone wrong. Thanks in advance for your comments. Keith.
I had an issue a couple of days back with re-framed GP40 that was partially short circuit and I tracked it to the decoder touching the frame between the connection points. I posted about it http://www.trainboard.com/grapevine/showthread.php?t=115785]here[/url]. This may be of help in determining the problem. Though it's an inconvenience, at least you have the goof proof warranty backing you up.
I just installed two of them in Atlas GP7's. I didn't have any issues with mine. I did use kapton tape to insulate the frame by where the motor contacts stick up. I pulled the motor and put a wrap around on each side of the frame there. I had an issue once with an Atlas GP38 with a factory installed decoder where one of the contacts touched the frame and the locomotive programmed properly and then when I placed it on the main it shot off at full speed and then shot flames and the magic puff of smoke from the decoder. Since then I always pull the motor and take a wrap with the kapton tape by the motor contacts, just in case. After that incident I also made a reduced voltage test track as recommended by MRC and NCE. I test every locomotive there that I have installed a decoder in or that I have disassembled for any reason before I place it on the main. I do this even if I had a good continuity/no continuity check. I made it by running a drop from my main out on my system and wiring a 33 ohm 1/2 watt resitor in series on one of the power feeds to the Test Track. If you have an install that looks good and is not, it will smoke the Test Track resistor before it it blows the decoder. Wanna know how I know? Leave the locmotive on the Test Track for a couple of minutes and run it back and forth, test your lights, etc. If the resistor doesn't start smoking the install is probably good. You can get a five pack of those resistors at Radio Shack for $0.99. The two DPST switches are wired in so that I can kill power to the Program Track and the Test Track when I am not using them. I just don't want them to be hot and someone lay something on them by accident and cause a problem or something.
Welcome to TrainBoard! Over 25 installs and only one I had issue with was with a frame substitution job and that Otherwise, the TCS decoders have been faultless so I am surprised to say the least. The only 'Lenz' decoders I have are a pair of Atlas factory fitted in RS11's. They work fine except for the 2K buzz and one Digitrax in a B39-8 I haven't had much to do with (yet).
I had virtually the same experience after I overhauled an Atlas diesel where I had the frames apart. When I put the loco together and put it on the track it worked well with no problems. I took it to my business to run it on a small test track I had there and I started to get very hesitant running, then nothing. I found out that one of the motor spring connectors had been making a partial contact with a side frame and the resulting short had eventually blown the output of the decoder. Atlas don't put any insulation on the frames around the motor contact strips and I learned the hard way that tape is necessary to prevent any shorts happening - especially when it can be quite difficult to see what's happening with the motor contacts when the decoder is fitted. Jim.
