When a blue tower beacon is lit, what condition is present?

A blue tower beacon typically indicates a specific operating condition in electrical switchgear systems, often associated with safety and maintenance notifications. When the blue tower beacon is lit, it usually signals a "Dead Bus" condition. This means that a portion of the electrical system, specifically the bus, is de-energized and not carrying any electrical load. The alert serves an essential purpose: it informs operators and maintenance personnel that the area is safe from electric power but requires precautions for work or other activities.

This indication is vital for ensuring safety protocols are followed when maintenance is performed on switchgear or related equipment. It allows technicians to proceed with confidence that the system is not live, thus helping to prevent accidents.

Other conditions such as normal operational conditions, low load conditions, or maintenance required might trigger different indicators (like green or yellow lights), which do not imply that the system is entirely de-energized. The blue beacon specifically is associated with the safety and readiness to work on the dead bus.