• Preface
  Preface
  
• Contents
  Contents
  
• Introduction
  Introduction
  
• Electrical Basics
  Voltage, Current and RMS
  
  Impedance
  
  Power
  
• Types of UPS
  Types of UPS
  
  Online Double Conversion UPS Systems
  
  Line Interactive UPS Systems
  
  Offline UPS Systems
  
  Sinewave Systems
  
  Squarewave Systems
  
  UPS Operation Demo
  
  EN62040-3 UPS Classification
  
• Types of Power Problems
  Types of Power Problems
  
  Black Outs
  
  Brown Outs
  
  White Outs
  
  Transients and Surges
  
• More Electrics
  Power Factor
  

So, what is an Uninterruptible Power Supply, or more commonly referred to as a UPS System?

In it's simplest form a UPS is a device that converts stored energy into electrical energy to provide power continuity in the event of the utility voltage changing to unsafe levels (either too high, too low or non-existent).

The energy storage is usually in the form of lead acid batteries, however this is not always the case. Recent developments have introduced fuel cells as energy storage, mechanical systems such as flywheels, compressed air, and ultra-capacitors to name a few. However, by far the most common storage mechanism is Valve Regulated Sealed Lead Acid Batteries (VRSLA). This is what we will concentrate on in this site.

However, that is not all a UPS does. There are many problems that can occur on the mains supply which can cause disruption to your electrical equipment, not all of which are as obvious as a power cut. We'll go into some of these problems later and explain how each type of UPS is designed to provide protection against such events.

Although, we've kept the technical stuff to a minimum there are some terms that you'll need to know, so we'll start with a brief introduction of simple electricity.