Features automatic weapons such magnetic switch circuit is very simple, reliable, low failure rate, good versatility, can be used to output the performance or can be converted
into mechanical displacement of the occasion. (2) is a circuit diagram using the Hall switch (SH) magnetron devices. When the magnet away from the Hall switch circuit, due to the positive effect of the fixed bias magnet, the Hall switch circuit is turned on, the output is low, the thyristor is turned off, AC contactor KM release. While the magnet is moving into sensitive areas Hall switch when in the reverse magnetic field whose output suddenly promoted to the high level, by making the diode VD VT conduction, KM pull. Adjust RP1 and RP2, can take into account the sensitivity and reliable offerings (to prevent false triggering VT). Figure 18-29b is in magnetron device using reed (KP) is. When the magnet away from the KR, KR contacts open, transistor is turned off, the relay is KD released. In the magnet close to the KP, KP contact closure, KD suction units, relay contacts KD string controlled electrical equipment control system circuit, so the movement of the magnet and its location determines the working status of the device.. (3) analysis of the circuit shown in circles 18-29, KD if the relay coil current is small, or low voltage electrical equipment, current is very small, it can be directly connected in series with the reed pipe, with less than other components. Reed contacts generally small capacity, control large capacity of the load resistance, we must use transistors, relay embroidery, or the like contactor thyristor as voltage, current, or persuade amplifying. Since the thyristor gate voltage is low, current is very small, therefore, the reed switch connected to the thyristor control pole circuit required, electrical equipment connected to the thyristor main road in the pigsty, which is a better solution.