What does the term 'phase rotation' refer to in electrical systems?

Phase rotation refers to the specific order in which the phases of a three-phase electrical system are arranged and connected. In a three-phase system, there are typically three individual conductors, each representing a phase (often labeled as phase A, phase B, and phase C). The sequence in which these phases energize during each cycle determines the direction of rotation in motors and other equipment connected to the system.

Correct phase rotation ensures that three-phase motors and systems operate efficiently and as intended. If the phase rotation is incorrect, it can lead to motors running in reverse, which can cause mechanical stress or damage to equipment, as well as affect system stability.

Understanding phase rotation is critical for ensuring proper operation in three-phase power systems and for the safe and effective commissioning of machinery and electrical devices. The concept is foundational for electrical technicians and engineers working with complex electrical systems.