. Battery Failures Problem: The most common problem with a UPS is the failure of its battery. Over time, batteries deteriorate and lose their ability to hold a charge, which decreases the runtime of the UPS battery backup during outages, causing UPS not to give backup. Causes: Improper maintenance, high ambient temperature, and infrequent use can accelerate battery wear, leading... https://mspwebstore.com/blog-detail/Common-UPS-Problems-and-How-APC-Systems-Solve-Them