Most inductive loop vehicle detectors work by sensing the change in the earths electormagnetic field when a mass of metal (your car, motorcycle or bike) moves through it. the square cuts in the road is where they lay wire to form an inductor...this inductor is part of a tuned circuit that can detect this change in the earths field.
There are several different types of loops, some are specifically wound in both tuns and geometry to detect certain types of vehicles (cars, motorcycles, bicycles, etc)
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Most inductive loop vehicle detectors work by sensing the change in the earths electormagnetic field when a mass of metal (your car, motorcycle or bike) moves through it. the square cuts in the road is where they lay wire to form an inductor...this inductor is part of a tuned circuit that can detect this change in the earths field. There are several different types of loops, some are specifically wound in both tuns and geometry to detect certain types of vehicles (cars, motorcycles, bicycles, etc)