IG746

The 4 channel loop detector IG746 is used for signal output in traffic light installations via switching outputs and CAN bus as well as for traffic counting.

FUNCTIONAL DESCRIPTION:

The CAN protocol is specifically designed for traffic control applications. Standard data contents are e. g. detection status, error status and detection edges with occupancy time respectifly time gap. In double loop systems additional data as vehicle speed, length and direction are transmitted. Via the CAN bus interface the full parameterization of the detector is also possible.

The detector processes the loops one after the other in a predetermined sequence (multiplex mode); i.e. there is always only one loop switched as inductance L to the LC oscillating circuit of the detector. Since there is always only current flow through one loop, the channels of a detector cannot interfere with each other.

If a metallic object is located within the range of action of the connected induction loop, the frequency of the LC oscillator also changes owing to reduction in the loop inductance. This change is determined by the detector evaluation circuit and, if the turn-on threshold is exceeded, a busy signal occurs on the switching outputs of the channel (electronic relay and open collector). Different output functions, e.g. presence signal and pulse signal are possible.