Locomotive control can be synchronous, whereby control commands made by the engineer in the Lead unit are transmitted instantly via radio telemetry to—and are followed immediately by—all Remote units in the train, or independent whereby the engineer may set up and independently operate the Remote locomotives as a ‘front’ and a ‘back’ group (or with Locotrol III and subsequent versions; as ‘Lead’, ‘Remote-forward’, Remote-intermediate’, ‘Remoterear’, and ‘Remote-trail’ groups—this latter at the rear of the train).
The front group always includes the Lead locomotive, and all Remote locomotives in the front group follow the commands made by the engineer using the Lead locomotive controls. Which Remote locomotives are in the front or back groups are selectable by the engineer in real time. One DP train cannot affect another DP train or another individual DP-equipped locomotive not in a train; and an individual DP-equipped locomotive not in a train cannot affect any DP train or other individual DP locomotive regardless of proximity.