What is the difference between watts and volt-amperes?

You’ll notice that specs for uninterruptible power systems seldom if ever mention watts (W), but instead speak in terms of volt-amperes (VA). Watts refer to “real power,” while volt-amperes refer to “apparent power.” Both are simply the product of voltage (V) multiplied by amperage (A). Thus, a device drawing 3 amps at 120 volts would be rated at 360 watts or 360 volt-amperes.… Read more

Your switchgear does more than just switch

The electrical distribution of power from your local utility to the individual pieces of equipment inside your datacenter, factory, or business is handled by your switchgear.

Your switchgear can be relatively simple, such as service-entrance circuit-breakers and GFCIs, but also might include highly sophisticated, digitally controlled switches that move the current demand from one source of power to another: most typically from the local utility to a UPS or to a generator depending on the circumstances.… Read more