APC wrote ...
This note helps explain the differences between Watts and VA and explains how the terms are correctly and incorrectly used in specifying power protection equipment. Many people are confused about the distinction between the Watt and Volt-Amp (V-A) measures for UPS load sizing. Many manufacturers of UPS and load equipment add to this confusion by failing to distinguish between these measures.
get the PDF here:
http://www.apcmedia.com/salestools/SADE-5TNQYF_R0_EN.pdf
APC wrote ...
Many of the mysteries of equipment failure, downtime, software and data corruption, are the result of a problematic supply of power. There is also a common problem with describing power problems in a standard way. This white paper will describe the most common types of power disturbances, what can cause them, what they can do to your critical equipment, and how to safeguard your equipment, using the IEEE standards for describing power quality problems.
Get the PDF White Paper here:
http://www.apcmedia.com/salestools/VAVR-5WKLPK_R0_EN.pdf
