ON-LINE UPS with VFI technology (output voltage and frequency are independent of their input values) are characterized by double energy conversion. The input mains voltage is first converted to DC and this is subsequently converted to output AC voltage. The UPS keeps the batteries charged.
Switching to the mode of powering the load from the batteries takes place without interrupting the supply of electricity. High filtering of electrical faults is achieved by double conversion. networks and stabilization of the output voltage in case of fluctuating input voltage, which ensures a high quality of the output voltage.
On-line UPS provide the highest level of load protection. Their sophisticated features and overall power protection make them suitable for critical loads in banking, healthcare, telecommunications, transportation, control rooms, medium and large data centers.