An uninterruptible power supply/battery backup (UPS/BBU) system provides emergency power to connected equipment by supplying power from a separate source (batteries) when utility power is not available. The system may also function as a power conditioner and/or voltage regulation device. UPS/BBU systems consist of an enclosure or cabinet, the batteries, the power inverter/conditioner, a battery charger (usually integral to the inverter), and automatic and manual bypass switches.