An Uninterruptible Power Supply (UPS) is an electrical device that provides emergency power to a connected load when the main power source fails. It's more than just a battery backup, as it also conditions the incoming power to protect equipment from various electrical anomalies. The core function of a UPS is to bridge the gap between a power outage and the activation of a standby generator or to provide enough time for a safe shutdown of sensitive equipment. . There are three main types of UPS systems: standby (offline), line-interactive, and online double-conversion. The online double-conversion model offers the highest level of protection by continuously converting incoming AC power to DC and then back to AC, ensuring a constant and clean power supply with zero transfer time during an outage.