This uninterruptible power supply (UPS) controller UB10.242 is an addition to standard 24 V power supplies to bridge power failures of remote or emergency systems which must be kept fully in operation for e.g. 72 hr. The DC-UPS includes an internal temperature sensor and a professional battery management system which charges and monitors the battery to achieve the longest battery service life as well as many diagnostic functions that ensure a reliable operation of the entire system. A unique feature of the UB10 series is that only one 12 V battery is required to buffer the 24 V output. This makes matching batteries unnecessary and allows a precise battery charging and testing.