Online Uninterruptible Power Supply System is equipped with batteries that are always connected to the inverter, so that no power transfer switches are necessary. The Uninterruptible Power Supply System is designed in such a way that when a power loss occurs, the rectifier simply drops out of the circuit and the batteries keep the power steady and unchanged. The Uninterruptible Power Supply System is made using quality grade material. Online Uninterruptible Power Supply System offers effective performance and ensures long functional life.