About the Treadle
Treadle units are activated by the forward or reverse rolling motion of the vehicle tires. The strips are activated in a sequential manner, due to their placement and separation in the treadle body.
It is this sequential operation which provides directional information, and provides a measure of security from “incidental” activation, such as a pedestrian walking on the treadle body. In every case, it requires two strip activations to be considered a complete crossing.