You know you need to back up your electronics, but how much back up do you really need? Unfortunately, the most difficult part in buying a UPS is determining how much UPS is right for you.

Determining power consumption

• Make sure that all the devices you need on battery backup are located in close proximity to each other.

• Check each device for its current rating in amps. (Usually located on a label or plaque near the power cord. For PC power supplies, you may need to open your computer case.)

• Multiply the current ratings by 120 (the voltage rating of the wall outlet)

The figures you have just calculated are the maximum power needs (in Watts) of the devices you are looking to protect.

Say your computer draws 2 Amps, and your monitor draws 1 Amp: 120V x 3A = 360W

UPS’s are usually rated in Volt Amps (VA) which is not the same as Watts. Our UPS’s are rated from power factor of .6 (60% of the VA rating is what you can assume the UPS will provide in Wattage) to a power factor of .9 and over in our high end products.

We suggest that you be very conservative in your estimate of power draw on your UPS, as you will undoubtedly add more devices that you will want to protect in the future, and as batteries age, the power output can drop.

Take the example above, where the computer and monitor draw 360W. Our 700VA standby unit has a power factor of .6 (420W). With new batteries, this unit will continue to power that load for 4 minutes. Our 750VA Line-interactive unit has a power factor of .67 (503W). In contrast, with new batteries, this unit will continue to power that load for approximately 12 minutes.

Depending on the conditions of utility power in your area, and how important it is to keep power to the devices you plan to protect, can help you determine just how much UPS you really need.