Star-delta-starters are employed with asynchronous motors of 4 kW and larger to prevent excessive startup currents. Unlike hand-operated star-delta-starters these starters either have their own logic controller or can be operated manually, so that the starting time can be optimized for every application.
Starting is implemented by means of a contactor controller, a special time relay (KLIBO-Star-Delta-Brake-Timer), and an integrated overload relay. High operational reliability is achieved by observing important switching sequences and locking the controls.
The switching time should be set in such a way that 80% of nominal speed are achieved when the switch-over from star to delta takes place. A motor suited for star-delta must have a voltage rating of 380 V /660 V or delta 380 V. Six external winding terminals are necessary to connect such motors.
Star-delta-starters are used in machine tools, wood processing machines, compressors etc. These starters may be equipped with our new brake controls (see Option “electronic brakes”).