I seriously don't recommended using it (at least without doing some researches first). Many UPS units are optimized for 50%-80% load. If you put a very light l

I seriously don't recommended using it (at least without doing some researches first). Many UPS units are optimized for 50%-80% load. If you put a very light load on an office UPS, like a lamp, a modem or a Raspberry Pi, some UPS's inverter will drain itself quicker before the load even drains battery. Some UPS have a light-load powersave feature, they don't even activate themselves when there's little load. Also, most office UPS is designed for short loss of power, not as a longterm battery-backup, so it will keep beeping until it's dead. Depending on what the OP is trying to do, this may be unacceptable. Due to the above problems. If I chose to use a 110/220 V UPS, I would at least try finding one designed to supply backup power to routers and modems to ensure that they don't have this problem.