We get lots of questions about the difference between “Offline”, “LineInteractive – Step Wave”, Line Interactive – Sine Wave” and “On Line” Here are a few notes to help you along.
Offline means that the output of the UPS is dependentupon the input supply, for both frequency and voltage. Whatever is supplied tothe input of the UPS, is what will be fed out of the UPS. This is the lowestlevel of protection, this is purely battery backup only.
Line interactive means the output of the UPS isindependent of the input voltage, so the UPS can change the input voltagesupply to ensure that the output voltage remains stable. Line interactiveoutput frequency will be the same as what is fed by the mains input.
Online UPS are independent of both input frequency andvoltage. Irrespective of the supply, a true online UPS will ensure a stableoutput voltage...