Power Protection - The UPS

Why do I need power protection?

Many people are under the misconception that a personal computer is just the same as any other domestic appliance such as a TV and have little comprehension of the complex electronics that enable it to function. We've all heard of TV's or similar having been blown up by a lightning strike or similar, but the stark reality is that they are many times more sensitive than this. You will all have noticed the lights flicker on occasion and thought nothing of it as everything seems to be ok afterwards and total power cuts in the UK are, thankfully, only very rare.

Personal computers are very sensitive to spikes, surges and brownouts and these events can cause irrepairable damage to them. More often however, no apparent damage is done but files may be corrupted and may this may not become apparant until long after the event particularly in large datafiles such as accounts and databases. Modern operating systems can often repair some of this damage but it's a ticking bomb and one day you won't be so lucky!

What can be done to protect against this damage?

There are various products on the market at a range of prices to help safeguard against power disruptions. Spike or surge supressors are a bare minimum and can remove significant spikes. Surges and spikes tend to burn out sensitive electronic componants by over-voltage which usually results in obvious damage and is easily diagnosed.

More sinister damage (and harder to trace) is caused by voltage failure - less so all out power-cuts but extended brownouts. These are where the power remains on but the voltage drops by significant levels. The low voltages on computer boards can easily be maintained by modern computer power supplies so the computer usually continues to function but the 12 volt DC supply that feeds motors such as hard disks can easily drop in voltage. The result of this on a DC motor is reduced spin speed and if the computer is writing to the disk the data no longer fits into the space it should and instead over-writes adjoining 'sectors' - thus destroying other data. This type of event can be prevented by use of a UPS (Uninterruptable Power Supply). The UPS is a complex array of electronics and sensors and an internal battery - the mains voltage keeps the battery charged and electronics create a smoothed and constant output voltage - even when the power is removed completely! Almost all spikes, surges and brownouts are also removed. The time for which the computer can be run on the UPS battery will depend on the VA Rating of the UPS and the amount of load (wattage) of the connected equipment. 10-15 minutes is usually adequate but remember like all batteries, the amount of charge they hold deteriorates over time so is always pays to allow a little extra. A 500VA UPS is usually sufficient to run a single desktop PC. For heavier demands such as servers etc a higher rating is required.

Wiring Installation

This one escapes most people's attention but a good certificated wiring installation is just as important. Bad earthing, deteriorated cabling, loose connetions etc can all contribute to power problems. We can recommend electricians to undertake testing for you if you require help with this.