Bypass circuit [t-head2-pg]

After completion of the acceleration phase (full mains voltage reached), the soft starter M4 actuates the bypass contactor. Thus, the motor is directly connected with the mains.

Advantage:

The bypass contactor is now switched to a no-load state and can therefore be AC-1 rated.

If an immediate voltage switch-off is required due to an emergency stop the bypass contactor must also switch the motor load. In this case it must be AC-3 rated.

Actuation [t-head3]

Emergency-Stop

S1: Off (unguided deceleration)

S2: On

Enable

Soft start/soft stop