Our club is being told by someone considered to be an expert in DCC installation and operation that we should never place an engine on a “hot track.” That doing so over a period of time will “kill” the decoder. Even after a derailment, an engine should be placed back on the track with the power off. Is this something that you are aware of?  Rick C......Kings Point Model Railroad Club Sun City Center, Florida

Hi Rick, there are at least two issues with placing a locomotive onto a live DCC track. The first is that most sound equipped engines now use a relatively large filter capacitor on the input to prevent sound loss due to frogs, dirt, etc. On an unpowered engine, this capacitor is discharged. When you place it on the tracks, it is the equivalent of a dead short across the rails for the period of time it takes the capacitor to charge. As a result, you may get some arcing on the wheels as they make/break contact to the rail. Once in a while, OK, but over time, this can damage the wheels. The other issue is that you are unlikely to place the engine cleanly on the track. What I mean by this is that it is likely to make/break contact to the rails (as I mentioned above) as you juggle it around get it on the track. This can turn the decoder on and off with some very short duty cycles. Some decoders have been known to loose their programming with this type of pulsing. The bottom line is that good general practice is to turn the track off before placing an engine on the rails. On the other hand, once in a while will probably be OK.