Cam controllers on lifting crane machines

The cam controller realizes the forward and reverse directions of the motor through the closing sequence of its power contacts.

When the cam controller is used, the electromagnetic coil of the actuator is connected to the stator line on the motor, and it is powered  on and off at the same time as the motor. The master controller is matched with the magnetic control panel to become a complete control system. The commands issued by the master controller are realized by the corresponding contactors on the magnetic control panel to start, brake and adjust the speed and reversal.

The master controller often works with two kinds of  magnetic control panels, one is the PQR9A type and the other is the PQY type. The former master controller is 6~0~6 gears, and the latter is 3~0~3 gears. There is no big difference between the two controllers and the cam controller, it is the difference in the position of the handle.

Double girder gantry crane

Single girder overhead crane