ABB rotary handles are essentially a switch that can be used to control different circuit operations using rotation. They are an isolation control accessory and can be used together with devices, to help achieve specific functions.
An example of where a rotary handle can be used effectively is in conjunction with an MCCB. An MCCB has three main functions, protection against overload, switching a circuit on and off and protection against electrical faults. A regular handle/switch wouldnt allow the MCCB to achieve these functions as interruption of large currents during faults can cause sparks. This is where the use of a rotary handle is the much safer choice. When used with an MCCB, an ABB rotary handle gives a clear visual indication of the three positions, on, off and trip, offering safety and simplicity for the user. When used in conjunction with an MCCB, a rotary handle allows switching of the breaker behind a closed door, compartment isolation before entry and door interlocking.