What does a blue tower beacon indicate?

A blue tower beacon is typically used in electrical systems and switchgear applications to convey specific operational statuses. When a blue beacon is illuminated, it signifies a Dead Bus condition. This is particularly critical in power distribution systems, indicating that the busbars aren't energized and that there is no power available at that location.

Understanding the importance of this signal is essential because a Dead Bus condition needs immediate attention to ensure safety and proper functioning of electrical systems. Personnel and operators must recognize this alert to take appropriate action, such as resetting or troubleshooting the system to restore power.

Other options, while relevant in different contexts, do not appropriately match the indication given by a blue tower beacon. For example, standby mode or operational generators might be indicated by different colored beacons or signals in the system. The control circuits being active is also denoted differently, since active control signals are not necessarily tied to an alerting status like a Dead Bus condition.