Electromagnets can be divided into AC electromagnets and DC electromagnets according to the voltage of the suction coil
The use voltage of AC electromagnet is generally AC 110V / 220V, and the electrical circuit configuration is simple. AC electromagnet has large starting force and short commutation time. However, the reversing impact is large and the temperature rises during operation (the shell is equipped with heat dissipation ribs); When the valve core is stuck, the electromagnet is easy to burn out due to excessive current and poor reliability. Therefore, the switching frequency shall not exceed 30 times / min and the service life is short.
DC electromagnets generally use 12 / 24V DC voltage, so special DC power supply is required. The utility model has the advantages of small volume, reliable operation, small switching frequency of 120 times / min, small commutation impact and long service life. But the starting force is smaller than that of AC electromagnet.