How to protect computer from power outage?


We often get asked ‘How to protect computer from power outage?’ Use a UPS (Uninterruptible Power Supply).

Let’s dive into the details

No matter where you are or what you’re doing, if your computer suddenly turns off for no apparent reason it can be very disconcerting. While this issue may seem like only a minor nuisance at first if left unchecked could cause significant damage to sensitive data stored on your hard disk drive (HDD). Within minutes after powering down your system, files can begin corrupting which renders them unreadable. If these corrupted files contain photos or other important documents, they may be gone forever.

Knowing how to protect your computer from sudden power loss can help prevent many headaches down the road.

Fortunately, there are a few things you can do to shield it from an untimely demise.

The first thing you should do is install an Uninterruptible Power Supply (UPS) device.

What is a UPS (Uninterruptible Power Supply)?

An Uninterruptible Power Supply (UPS) is a power supply that can provide protection from unexpected power outages. It does this by monitoring the input line voltage and responding when there is an imminent loss of power. A UPS system uses batteries, an inverter, or both to supply uninterrupted electrical power in the event of utility-supply failure or fluctuation.

A UPS ensures that no matter what happens to the power supply coming into your home, whether it be through natural or unnatural causes, electricity will still flow uninterrupted to your PC. These units are equipped with batteries that kick in automatically if irregularities are detected by its sensors.

The use of an uninterruptible power supply (UPS) with a battery backup can be used to protect your equipment from a short-term power outage or lightning strike. An Uninterruptible Power Supply communicates with the connected equipment by monitoring the electrical noise on the line, thus it has a chance to gracefully shut down before a hard reset is necessary. But all UPSes have a limited amount of time they can keep your system on without being connected to AC power, so you’ll need additional battery backup if the outage lasts longer than that.

Surge protectors vs UPS

Surge protectors are designed to regulate power surges within your home and do so by safely passing an excess voltage through its components to the ground wire. If there is too much electricity flowing through the device, one of its fuses will “blow” (or melt) in order to prevent damage from occurring to your system. Note: A direct lightning strike on your house or apartment is not protected against only surge protectors – they will not stop that kind of current flow!

What is a limitation of a UPS?

The most important thing to remember is that these devices do not protect against electrical fires or burns. It’s always best to protect yourself by keeping your PC on a desk rather than underneath it, placing computers so they do not overheat, and keeping them at least three feet away from other electronics for optimal ventilation. These precautions help ensure proper airflow around the components so they do not become overheated and combustible. Finally, you can buy special surge-protected power bars for multi-plug devices such as televisions, microwaves, etc… which can be very effective in protecting your computer and home against power surges.

How does a UPS work?

A UPS contains capacitors that charge when current flows into them from the mains socket. During normal operation, the capacitors supply current to the connected equipment. When a mains failure occurs, all of the equipment connected to the UPS will be switched off and disconnected from the mains supply. The battery within the UPS then supplies current to your system until it is exhausted or a normal electrical supply is restored, at which point switching over back to AC mains power takes place automatically without any intervention from you.


UPS makes good surge protectors as well as gives short-term backup protection during power failures. In some cases, however, more extensive protection can be provided by plugging PCs into their own protected ring main. This is known as an ‘Uninterruptible Network’ or UPN and provides guaranteed shutdown of specific machines in the event of an extended power failure.

This is a system for protecting servers, modems, and other systems from a complete power-down. An uninterrupted power supply can be seen as a backup battery that keeps the electrical current going to the PC during the brief period when the power fails during blackouts. There are ‘line interactive’ UPS models that have transformers capable of accepting large voltage drop from your building wiring, decreasing by half or more any substantial sag in the incoming mains supply. When this happens, instead of taking 3600 watts from your mains supply it takes 1800 watts for an extended period without dropping out. These kinds of models have better features than basic line backups but they often cost more as well.


Types of UPSs

Some UPS devices allow you to specify a window of time permitting power failure to occur before automatically shutting down. This may be useful if you are using your PC for messaging since it will allow time for the program to save its files and shut down properly, or for a database application that needs to clean up its database.

Other UPS devices have ‘true online’ power sources, meaning they can accept large surges from your main power source without themselves requiring a surge protector. If the main voltage fails but an overvoltage circuit remains intact, they can continue providing power throughout the blackout period provided by batteries only until the inverter overheats and shuts off. In this case, it is important to install a suitable surge protector on all incoming AC wiring inside your building. With these models, you need not worry about installing an expensive surge protector on the incoming line or about using fuses with enough capacity to withstand extremely high current levels. Most UPS models will continue to provide their basic protection (battery backup) even when connected to an overvoltage circuit; in this case, they will simply shut down when the batteries are exhausted after a few minutes or hours of non-operation. However, if during this brief breakdown period the battery charger was triggered by mains power (from lightning) to recharge its batteries, anything connected to it – including computers – would be fried beyond repair since there would be no way for the inverter circuitry or external components to detect that mains power was absent and stop charging.

Importance of using a UPS for your business

UPS can provide sufficient power to keep most business-critical systems running for a short period of time until the power is restored. If there is a blackout, your computer and network will continue to run normally and you won’t be losing any work or data. Another advantage to using a UPS is that it protects sensitive equipment from any voltage spikes or surges which could otherwise damage them causing costly pc repairs later on. A sudden loss of energy supply could provoke all types of problems such as computers freezing up, lines breaking down, applications failing and many more technical issues that would take hours to fix.

What are recommended brands for a UPS?

  1. Eaton
  2. APC
  3. CyberPower

Optional Tip

Another useful trick that some people employ is unplugging their PC completely when it’s not in use for extended periods of time… this is a good practice if you’re an avid gamer as the computer will not accidentally “wake up” from standby mode and suffer damage as a result.


In computers, a UPS protects hardware from damage caused by power outage and improper shutdowns. It allows a computer to shut down gracefully when utility power fails. A UPS may also include a surge protector in which case it will typically suppress all normal house wiring voltages. On large systems, the devices are typically rack-mounted for convenience, if not permanently installed within an equipment rack.

I am a computer engineer holding a bachelor's degree in Computer Science, complemented by a Master's in Business Administration from University of Strathclyde, Scotland. I currently work as a Senior IT Consultant in Melbourne, Australia. With over 15 years of...