Bachman N scale H16-44

[Rich_S]

Hello Group,

   I've run into a problem with my "N" scale Bachmann H16-44 locomotive that has the Bachmann light board with the DCC plug in connector. I wired a Digitrax DZ143 to the light board per Bachmann's instructions. I then was able to program the decoder to use a new 2 digit address. I was also able to modify the default values in CV2, CV5 and CV6 for start, mid-range and full speed values. I then placed the loco on my layout, the lights and direction responded as expected. I then set the throttle to 25, to allow the locomotive to make a few break in runs around the layout. On the third lap around my small HCD layout, the engine quit and as Digitrax states, I let the smoke out of the decoder. I had made sure before even placing the locomotive on to the programming track that all of the wires were insulated. Not only was the decoder damaged and needed repaired, the actual circuit board was damaged as well.

   Next, I removed the factory installed light board and hard wired the decoder directly to the motor and the frame. I made sure all connections were insulated with heat shrink tubing. I was again able to program the decoder without issues. This time after about 6 months of flawless running, everything goes up in smoke. The engine runs fine on DC power, so at this point I'm not sure why the first decoder went up in smoke after only a few hours of use and the second decoder went up in smoke in 6 months of use. Has anyone else had these issues with the N scale Bachman H16-44?

Rich S.
Modeling the P&WV in "N" scale. 

[peteski]

To me this sounds like you are ending up with an intermittent short of the motor leads to the track power leads.  When in DC, it would not cause problem (since the track power is actually supposed to be connected to the motor).  But when using DCC, track power and motor have to be isolated from each other.  If they end up shortign out then the decoder usually smokes.

Nect time you install the decoder make absolutely sure that there is no possibility of the track power leads ever coming in contact with the motor circuitry.

[Rich_S]

Hi Peteski, I hard wired the decoder to the motor, then used heat shrink tube on all connections. I even used electrical tape on any area I felt might come in contact with the frame. I even checked the connections with a meter to make sure the motor was not grounded to the frame. The only thing I have not tried is changing the actual motor. I was wondering if anyone else ever ran into any issues with these engines? Maybe a bad batch of motors? It's strange two decoders smoked on the same engine and the latest one was after 6 months of successful running.

Rich S.
Modeling the P&WV in "N" scale.