What are they?
Brownouts are periods of low voltage in utility lines that can cause lights to dim and equipment to fail. Also known as voltage sags, this is the most common power problem, accounting for up to 87% of all power disturbances.
Where do they come from ?
Overburdened utilities sometimes reduce their voltage output to deal with high power. Recent statistics show that the US population tries to pull an average of 5% more than the utility companies can provide. The demand for power is rapidly increasing, but the supply of power is not. Damage to electrical lines and other factors can also cause utility brownouts. Locally, equipment that draws massive amounts of power such as motors, air conditioners, etc. that can cause momentary brownouts to occur. Undervoltages are often followed by overvoltages - "spikes" - which are also damaging to computer components and data.
What do they do?
Voltage variation can be the most damaging power problem to threaten equipment. All electronic devices expect to receive a steady voltage (120 VAC in North America) in order to operate correctly. Brownouts place undue strain on power supplies and other internal components, forcing them to work harder in order to function. Extended brownouts can destroy electrical components and cause data glitches and hardware failure.
What can be done?
Surge suppressors do only 1/2 the job. Line conditioners and Uninterruptible Power Supplies (UPS) are the best defense against both voltage problems. Designed to regulate both over and under voltages, Line Conditioners provide three separate levels of voltage correction. Adjusting computer-grade AC power meeting ANSI C84.1 specifications.