Conventional v. Command Operation

All this talk of command and conventional modes sounds complicated, but it's really quite simple. Conventional mode means that the trains are controlled by the amount of power sent to the track. The higher the track voltage is, the faster the trains will go, and all trains on the same track will react in the same way to changes in voltage. They will stop and start, speed and slow at the same rate. Track voltage is controlled by moving the throttle on the transformer. That is how all O Gauge trains were until the mid-1990s when command control technology became available.

Command mode is quite different. In a command environment, like Proto-Sound 2.0 with DCS, you control each train, switch, and accessory independently by communicating directly with it. You set the track voltage high, to ensure that the trains get enough power, then leave it alone. The remote control communicates with whichever engine or accessory you want to control and sends it a message telling it what to do. Because each locomotive or accessory responds to signals from the remote independently, you can conduct multiple operations at the same time. Thus, two or more engines can function on the same track at different speeds even though the track voltage is the same and is controlled by the same transformer. Command mode allows for much more realistic - and interesting - operation of a model railroad.

M.T.H.'s Proto-Sound 2.0 engines are capable of operating in either conventional or command mode.