Backup Power (UPS)

Power factor

Electric systems that operate inefficiently can rack up hefty additional charges from utility companies ── fees that many customers don’t even realize they are paying. Determine if you are being assessed for power factor charges and discover how to reap energy savings by improving your system’s efficiency.

What is power factor?

Power factor (PF) is the ratio of working power (kW) to apparent power (kVA). Power factor is expressed as a dimensionless number between 0 and 1.0; it is a representation of how efficiently power is being drawn from the grid. A high ratio indicates a very efficient electrical system, while a low power factor denotes a poor utilization of electrical power, meaning a higher proportion of current is being drawn from the utility than is necessary

What is unity power factor?

When power factor is at unity, the voltage and current waves are aligned or in phase with one another. This is expressed as a PF of 1.0

Consider Power Factor when sizing a UPS

To correctly size a UPS, it is important to understand the relationship between watts and VA. However, we must first have a brief discussion about power terminology.

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Getting maximum power for your investment

In simple terms, imagine UPS power capacity as the amount of soda in a glass. The top of the glass represents the limit of apparent power the UPS will accept, or the VA. The actual liquid in the glass represents the real power of the UPS, or the Watts. Unless you desire a frothy glass of foam, you will want to maximize the actual amount of liquid in the glass. This—the Watts rating—is what you are paying for. When you are buying a UPS and sizing your equipment, pay attention to both the VA and Wattage ratings. This ensures you will get the maximum amount of power for your investment.

Eaton Unity Power Factor related UPS products

Eaton 5PX Gen 2 UPS

Eaton 9PX UPS

Eaton 9SX UPS

Eaton is an intelligent power management company dedicated to improving the quality of life and protecting the environment for people everywhere. We are guided by our commitment to do business right, to operate sustainably and to help our customers manage power ─ today and well into the future. By capitalizing on the global growth trends of electrification and digitalization, we’re accelerating the planet’s transition to renewable energy and helping to solve the world’s most urgent power management challenges.