SAFETY: IMpulse 3000 has been developed by Dual Inventive to provide track workers with visual confirmation that a track circuit operating device is shorting out the track circuits to indicate to the signalling systems that the track is occupied while maintenance takes place.

IMpulse 3000 sends coded signals through the rails once it is placed across the track. These pulsed signals are detected at the work site by a receiver placed between one of the rails and earth. A flashing green light and audible alerts confirm that the track circuit has been activated correctly, and IMpulse 3000 will emit a warning if it stops receiving pulses.