Vehicle Detection Loop Circuit

There is a misconception that inductive loop vehicle detection is based on metal mass.

Vehicle detection loop circuit. Basics of vehicle detection loops. In other words the relay circuit output will be closed opened the entire time that a vehicle is present over the loop and does not switch again until the vehicle drives away. Good practice dictates multiple loops and detectors in this situation. Loop detectors are used in conjunction with vehicle detection loops to detect vehicular traffic traveling or stopping overhead in a roadway these are commonly used to trigger traffic lights and you have undoubtedly traveled over thousands of them without even realizing it.

3 an oscillator circuit comprises a road loop 1 and a plurality of capacitors 2 arranged to be switched in circuit with the road loop 1 under the. If the inductive loop is placed correctly it will detect vehicle open gate and keep it open until the vehicle clears the gate. The electronics unit applies alternating current electrical energy onto the wire loops at frequencies between 10 khz to 200 khz. Loops are used to stop or reverse a moving gate to allow free exit from or entrance to a site or as an arming loop to allow entrance.

Vehicle detection loops called inductive loop traffic detectors can detect vehicles passing or arriving at a certain point for instance approaching a traffic light or in motorway traffic.