UPS the basics

VFI Voltage and Frequency Independent

As in the above line, VFI is an acronym for Voltage and Frequency Independent. It is sometimes the name given to the otherwise known online double conversion or dual conversion or simply online UPS technology.

This technology is the highest form of protection thanks to the creation of the output voltage and frequency from the UPS systems inverter. The inverter converts DC power back to AC and is the second conversion process within this type of UPS, following the rectifier which converts AC to DC.

For offline and line-interactive technology, they also have naming conventions which follow suit. These are VFD or Voltage and Frequency Dependent and VI or Voltage Independent, respectively. Where the line-interactive UPS smooths out voltage fluctuations making the output voltage independent of the input, offline tracks the input for both frequency and voltage.

Don’t let naming conventions confuse your decision making when it comes to UPS procurement.

VFI = Online
VI = Line-Interactive
VFD = Offline

For more help and understanding of what’s what with regard to UPS, get in touch with the team today!