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UPS Primer

This article explains the difference between Uninterruptible Power Supplies (UPS) and Power Strips.

There are 3 main types of power related devices, moving up in order of complexity:

  • Power Strip
  • PowerStrip/Surge Suppressor
  • Uninterruptible Power Supply (UPS)

Power Strips

The first and simplest is the power strip. The only function of a power strip is to increase the amount of receptacles available to plug devices into. The electric current from one wall outlet is basically rerouted to x amount of power strip outlets (normally 5).

While handy to have, use of power strips to provide PC power is bad for a number of reasons. First of all, if the power from the wall is cut off, then the power going to the strip is also cut off. All devices drawing power from it, including your PC are instantly turned off. Any work you may have had will probably be lost and you may even experience some hardware failure. Most popular hard drives spin at 7,200 revolutions per minute and require special instructions to safely "park" their read\write heads when they are turned off. Imagine the power suddenly being cut off to this device when it is spinning at full speed and doesn't have a chance to safely park the heads.

Power Strips/Surge Suppressors

A combo power strip/surge suppressor is slightly better at protecting your valuable computer components. Like a power strip, you are provided with more outlets, but unlike it, if there are any surges or spikes in the power being fed to the wall receptacle (up to 120 times a month in an average house), this device can actually stop a damaging surge from getting to your PCs delicate electronics. In addition to damaging hardware, surges can also corrupt data on your PC.

Although they may seem convenient, power strips/surge suppressors have some serious weaknesses. First of all, the surge stopping components (called Metal-Oxide Varistors (MOV)) in these types of suppressors will only protect your equipment through a few large surges and spikes. What's even worse, the fuse light can can continue to glow red as if it was still protecting your PC while it is doing anything but because of MOV breakdown.

Another weakness of power strips/surge suppressors is that they still don't give electronics the chance to safely shut down. To get this level of protection, you need to look to Uninterruptible Power Supplies.

Uninterruptible Power Supplies (UPS)

One of the most important pieces of hardware you can have for your PC is the UPS. A UPS is basically a large battery that is always on standby for a power failure. When the power goes out, the UPS kicks in and supplies a steady, though time-limited, amount of juice to the PC. The extra time you get allows you to exit out of any programs you were in, save your work and shut down the PC.

KoolGeeks strongly recommends that all users purchase a UPS for their PC setup. In the long run, you will easily recoup your investment both in the hardware life it helps to prolong, but also in the valuable data it will help you in keeping safe.

To calculate how powerful a UPS you need, you will have to do some investigating, but first a quick word about your average UPS. Most UPSs have two "groups" of plug receptacles — those that supply battery backup power/surge supression and those that supply only surge suppression. We recommend that you use the battery backup power/surge supression receptacles only for your PC and your monitor. In the event of power failure, you want to have these two units up and running so that you can then safely shut your system down. It is not essential to have power-hungry peripherals like your multimedia system playing music while you shut down. Non-essential devices such as this should go into the receptacle that provides only surge protection.

The next step is to find out how much charge the UPS needs to be able to hold to power your system. You can get this number by adding together the power usage of every device that goes into the battery backup/surge supression side of your UPS. This is where things gets a bit tricky.

First of all, UPS units are normally classified by a Volt Amperage number (ex. 500VA). However, the power needs of your devices will be expressed in Watts. The conversion is relatively easy. Once you have added up the wattage power needs of all items, multiply the total times .7 to get the VA needed. On average, a typical PC has a Power Supply Unit (PSU) rated at 450 watts. A modern LCD monitor consumes around 25 watts. To get the VA number, we add the two together and multiply the result times .7. ex. (450w + 25w) * .7 = 332.5 VA. Since manufacturers only make UPSs in industry accepted set increments (350VA, 500VA, 750VA), we will need to round our number up to the second value (500VA), so in this case, one would need a 500VA UPS to safely and effectively shut down a PC and monitor following a power outage.

If you would like to know exactly how much power each device is drawing, we highly recommend a innovative new device called a Electricity Load Meter and Monitor. This handy gadget will even do the conversion for you, allowing you to find out the exact VA needs of your UPS.