what is the working principle of the iron magnetic contact sensor ？

The iron metal magnetic contact sensor is a small accessory can used to monitor the state of the iron door. It is mainly divided into two parts: part with leads, which is installed on a fixed door frame, and the leads are connected to the controller; the second part does not have The lead is a magnetic body with a polarity different from that of the lead. It is installed on the movable door leaf and is aligned with the lead.

 the working principle of the iron magnetic contact sensor : There is a small reed switch in the door sensor with lead wire. When the door is not in direct contact with the wireless part (the door is open), the reed switch is normally open. The output signals of the two leads are normally open. Dry contact signal; when the door is closed, the two parts of the door magnet are facing each other, and the reed switch of the lead part is closed by the action of the magnetic field. At this time, the output signals of the two leads are normally closed dry contact signals. By switching the state of the door sensor, you can easily monitor whether the door is open or closed. 

Iron gate magnetic contact sensor has the characteristics of strong magnetic force, sensitive response, and easy installation. When installing, you only need to open a circular hole of corresponding size in the corresponding position of the door frame and door leaf, and then install the door magnet into the hole