According to control mode,following products are divided into：switch type、
integrated type and modulating type. 
Switch type input output switching value；integrated type input switching value output 4-20mA signal；modulating type input output 4-20mA signal.
According to explosion proof mode,following products are divided into：normal type and explosion proof type. 
Normal type is not explosion proof. Explosion proof type explosion proof electric motor is Exd II BT4.