Why are backup AC generators often included in commercial AC UPS and DC power systems?

Backup AC generators are included in commercial AC Uninterruptible Power Supplies (UPS) and DC power systems primarily to ensure a continuous and reliable power supply during extended utility outages. When a utility interruption occurs, the UPS can provide immediate power to critical equipment. However, this is typically limited by the battery capacity.

In scenarios where the outage is prolonged, a backup AC generator acts as a vital resource to maintain power. It allows the system to switch from battery power to generator power seamlessly, thereby extending the uptime of essential operations and protecting sensitive equipment from potential damage that might occur due to a loss of power.

This setup ensures that businesses can continue their operations without interruption, avoiding potential losses due to downtime. Therefore, including backup AC generators is crucial for maintaining system reliability and operational resilience in commercial power systems.