This plan requires either the wiring up of a double-pole double-throw switch on the reverse loop, or the use of a designated DCC accessory to enable this feature to work seamlessly. Trains are run from the terminating station at the top of the plan, around the main oval. They are then switched onto the reverse loop section, so that the train returns loco-first, and back into the station – the loco can then run around the train and start the cycle again. If steam operation is desired a turntable may be added, whilst a station could also be constructed in the reverse loop to give trains a chance to stop whilst the polarity switch is made.