Online UPS battery is constantly connected with the inverter, so its not important to have a power exchange switch. At the point when power is lost, the rectifier just drops out of the circuit and the batteries keep the stream of intensity enduring and unaltered. At the point when the power is re-established, the rectifier resumes conveying the vast majority of the heap and furthermore starts charging the batteries. However, the charging current might be constrained to keep the powerful rectifier from overheating the batteries and bubbling off the electrolyte. The most helpful favorable position of an online UPS, is its capacity to give an "electrical firewall" between the approaching utility power and touchy electronic gear.