Abstract: A system capable of identifying various possible technical malfunctions with an uninterruptible power supply system by detecting AC ripple on a power bus of the UPS system. A battery monitor is positioned on the terminal posts of one or more batteries of the UPS system. The monitor, since it is connected with the power bus, is configured to measure and/or record AC ripple on the power bus. At the monitor or by way of communicating the AC ripple to a remote database and server, excessive ripple changes may generate an alert when such changes exceed a threshold or may be viewed through a graphical user interface.