Many people will recognize these as risks of a power outage that can damage computers, but did you know that there are actually many different types of power anomalies? If the power dips for even a quarter of a second (250 milliseconds), your computer will use up its reserves of power and abruptly shut down after only 17 milliseconds.
Types of electrical anomalies
Sags, also known as brownouts and undervoltage, are temporary decreases of voltage levels. This is a very common problem, making up a majority of the power disruptions your computer will encounter. When a sag happens, computers may not get enough voltage to power all of its components. This can cause unseen data corruption, power loss to fans, and a freezing keyboard or mouse.
Electric companies purposefully induce sags in order to deal with periods of high power demands, such as high usage of air conditioners on a hot day.
Blackouts are when all power is lost. They are typically caused by power grid equipment failure, lightning, ice, car accidents, and natural disasters. When a blackout occurs, all data in your RAM and hard drive caches is lost. If critical system files like the File Allocation Table are damaged, it may render your hard drive inoperable.
A spike, also called an impulse, is a sudden and dramatic increase in voltage usually lasting less than one millisecond. It can be caused by a lightning strike or a large section of network equipment coming online. Spikes can cause catastrophic damage to computers, often overloading power supplies and burning circuit boards.
A surge, also referred to as a transient, is a short period of increased voltage typically lasting between 8 milliseconds and 2.5 seconds. Depending on the voltage, surges can cause damage similar to that of spikes.
Noise refers to both Electro-Magnetic Interference (EMI) and Radio Frequency Interference (RFI). Electrical power is transmitted with sine waves, usually as an alternating current (AC). The usage of many electronic devices in close proximity to each other can alter the pattern of these waves. When this occurs, it can result in overheating, data loss, and distorted audio or video.
Frequency shifts, also known as harmonic distortion, usually happen when lighting equipment shifts the sine wave frequency to something other than the standard 60 Hertz. This can result in the overheating of electrical wiring and power supply errors leading to unscheduled shut downs.
Preventing Damage
Surge protectors are the easiest and most affordable way to provide your equipment with an immediate layer of protection. When buying a surge protector, you want a high amount of joules and low let-through voltage.
Joules are basically how much energy the device can absorb over its lifetime. Let-through voltage is how much voltage is passed on to connected devices when the surge protector is hit with a 6,000-volt surge.
The best surge protectors will even have outlets for phone, TV, and USB cables. All of those cable types can be damaged from power surges. Just make sure you aren’t getting a power strip string only, which is simply an extension of a wall outlet and offers no protection.
For the best protection you will need an uninterruptible power supply (UPS). These power supplies will provide power to your equipment whenever it sags or stops completely. Most small power supplies will keep your computer running for about 10 minutes or just network equipment for about an hour. Having enough time to properly shut down your equipment can mean all the difference when it comes to saving your data and hardware.