Hi everyone, I wanted to share my recent experience with my APC Smart-UPS Modular (SUM3000RMXLI2U). It’s been a reliable unit for protecting my desktop setup from power outages, but recently I encountered an unexpected issue after a circuit breaker trip in my house. The UPS suddenly went dead and wouldn’t turn on, even after resetting the circuit.
I started by checking the batteries, which were fine, and noticed that the unit was unresponsive to the front panel controls. The inverter module only produced a single click, with no fans, beeps, or lights. When plugged in, the unit supplied power via bypass but wouldn’t charge the batteries.
After some research and testing, I removed the power module and top cover for a closer inspection. I probed the connectors and noticed some unusual voltage readings on the battery pins. This led me to suspect a failure in the inverter module or the brain board.
With my experience in electronics, I decided to test further with a DMM and oscilloscope. I found that the battery voltage was inconsistent and fluctuating, which suggested a problem with the module’s power regulation. I’m now considering sourcing replacement components or reaching out to APC support for assistance.
If anyone has encountered a similar issue or has insights, I’d greatly appreciate your input! I’m determined to resolve this and get my UPS back to full functionality. Thanks for your help!