The shifting of the motor takes the way of changing the winding connection, that is to say changing the speed of the pole by changing the number of pole pairs of the rotating magnetic field of the motor.
Two-speed motor (fan), usually low speed, sometimes the fan rotates at high speed, mainly by changing the winding connection mode of the motor coil by switching the following external control lines.
1. Two common poles of different pole pairs are embedded in the stator slot, and the connection of the stator windings of the motor is changed by switching the external control circuit to realize the change of the magnetic pole pairs;
2. Two independent windings of different pole pairs are embedded in the stator slot;
3. Two independent pole pairs of independent windings are embedded in the stator slot, and each winding can have different connections.
Two-speed motor control circuit diagram 
M8 distribution box is a kind of industrial connector. It is a device that converts a power supply or data into a shunt and outputs multiple current or data signals. General M8 distribution box refers to the line socket for M8 or M12 specifications of the distribution box. The difference between it and the ordinary socket is that the power output of the ordinary socket is only positive and negative two levels, or there is a ground wire, while the industrial distribution box, the power output is needle I/O port.
M8 Distribution Box,D-Sub Input Distribution Box,M8 distribution box 4 way, M8 Junction Box 8 port,M8 distribution box 12 way
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