Asynchronous motor controller CM 54-D

three-phasewith speed control

The CM 54-D unit simplifies control and movements in three-speed motors reducing the system to a minimum of 2 double pushbuttons or handler. The CM 54-D unit includes five inputs for the speed, turning direction and limiter signals, and four power outputs to act on the contactors. Between these inputs and outputs there is a microprocessor system that manages any three-speed motor movement, also including limiter management and action. The inputs and the outputs are galvanically isolated. The CM 54-D unit responds to any control unit, be it pushbuttons or handler, carrying out accelerations, decelerations and timing functions as programmed. Furthermore, the CM 54-D unit includes several operating modes that are user selectable from the microswitches located inside the unit. Control of 2/3 speed or Dahlander motors in tower and overhead cranes in hoisting, turning, trolley and traverse movements. Work sequences Basically, the CM 54-D unit times the input from the speed contactors to pass from 1st to 2nd and 2nd to 3rd gear, preventing any change in movement until the programmed time has elapsed "acceleration and deceleration time". For example, if the "acceleration and deceleration time" is 1.5 s and you wish to pass from standby to 3rd gear, the contactors will come in according to the following sequence: the first gear contactor will come in immediately, the second gear contactor will come in after 1.5 s and the third gear contact will come in after another 1.5 s.