UPS sizing is generally expressed in VA (apparent power) and Watts (real power). Power Factor is the ratio of the two. UPSs must be sized with both numbers taken into consideration.  While Watts expresses the real power that is being consumed, VA also expresses the maximum current value allowed. If either of these parameters are exceeded, the UPS will become overloaded. The relationship between Apparent Power and Real Power can be illustrated using the mug of beer picture below, showing that the more KW you have, the better the value.

The UPSs of old may have had only a .8PF, meaning that a 20KVA UPS was only capable of providing 16KW of real power. Today Power Factor Corrected IT load equipment have much higher watt values (kW=kVA) than previous generations of IT equipment, making the need for UPS systems with higher watt level capabilities all the more important. Today’s UPS systems with 1.0PF means that kVA is equal to KW of real power, increasing the real power output of the UPS by 25%.

XPC offers several unity power products:



Xtreme Power E90; Three-phase, 208/120 UPS

Visit the E90 product page to learn more:






Xtreme Power T91; Single Phase, 120 or 230V UPS

Visit the T91 product page to learn more:





Xtreme Power M90S; Modular Online, 208/230V UPS

Visit the M90S introduction page to learn more:






Future Unity Power Factor Products

        P91                                  TX91