Battery Backup Guide

Battery Backup

An uninterruptible power supply, or UPS, is a device or system that maintains a continuous supply of electric power to certain essential equipment that must not be shut down unexpectedly.

The equipment is inserted between a primary power source, such as a commercial utility, and the primary power input of equipment to be protected, for the purpose of eliminating the effects of a temporary power outage and transient anomalies. They are generally associated with telecommunications equipment, computer systems, and other facilities such as airport landing systems and air traffic control systems where even brief commercial power interruptions could cause injuries or fatalities, serious business disruption or data loss.

Historically a UPS was likely to be used in areas where the power supply is interrupted frequently (such as third world countries and some rural areas in first world countries). However that view has been changing in recent years as the number of instances of blackouts continues to increase. In North America in particular, the electrical grid is under increasing strain particularly during heavy demand periods such as summer when air conditioning use is at its highest.

In order to prevent blackouts, electrical utilities will, from time to time, use a process called load shedding. This reduces the amount of power being sent to the consumers but does not eliminate it entirely. This drop in voltage is also sometimes called a voltage sag or a brownout. A UPS will also protect equipment upon the occurrence of a brownout by using its internal batteries to correct the drop in voltage. The single biggest event that brought attention to the need for UPS power backup units was the 2003 North America blackout in the north-eastern US and eastern Canada.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Uninterruptible power supply"