For DC permanent magnet powered locomotives, the decoder must be electrically inserted between the track power pickups and the motor brushes. The most important part of any successful locomotive conversion is proper electrical isolation of the motor brush connections, so that they are driven exclusively by the decoder circuitry.

Note: Failure to isolate the motor will damage the decoder. Once the motor is isolated, you can proceed to follow the manufacturer's wiring diagram for installing the decoder.

Adapted from "Digital Command Control: The Wave of the Future", by Zana and A.J. Ireland.