What Use is a UPS?

Posted : 10 Dec 02

Many of you might even ask what is a UPS? A UPS is an uninterruptible power supply. These work by having a battery that cuts in whenever your power cuts off or varies from the standard 240V supply. I have had several people recently (both Mac and PC) who immediately or very soon after power surges or blackouts have had major (read expensive) problems with their computers. I have used a UPS myself for over 6 years. These aren't the sorts of things that you just put on servers but are of great use to just about anyone storing important data on a computer. How much is your data worth?

Most of you probably have surge protectors on your power boards. These are a good idea but really only offer very limited protection. They don't protect against :

Brown outs (where the voltage drops)
Blackout (no power supply at all)
Frequency variations (where the frequency varies from the normal 50Hz)
High voltage supply (where the mains power goes above 240V but not as a spike)
And several other power irregularities ...
Surge protectors really only protect you against power spikes and if the spike is big enough maybe not even then. Depends on the quality of the surge protector. If you have a $10 power board then you most likely just have a very basic surge protector. Dedicated surge protectors (generally) give you better protection but cost more.

The next step up is to have a power supply filter. This makes sure that you have 240V AC at 50Hz going into your computer and filters out all irregularities. These work well but provide no backup in the case of a blackout.

The final (and best) solution is to have a UPS. These devices provide you with power and filtering and unless the blackout goes for longer than the duration of the battery supply (generally around 5-19 minutes), you can just keep on working. Although if a blackout goes for more than a 15-30 seconds you may want to consider backing up and shutting down. They can even be setup to automatically shut down your computer if the power goes off (with appropriate software).

IBM published a white paper a few years ago indicating that the most common cause of premature hard disk failure was brownouts. Ever notice the lights dim in your room or the screen shrink on your display? That's a brownout at work. Some you may not even notice ... I don't have specific data I can quote but every computer engineer I have spoken and on line documentation from Quantum, Seagate and IBM to swears by (not at) the use of a UPS to prolong the life of your computer and hard drive.

If you are in an area where the power blacks out, surges, blinks or have a lot of electrical device problems then you may be a candidate for a UPS. Some country areas tend to get larger variation in their power supply than city users. Lower voltages are more often a problem in country areas also.

UPS's start at around $200 just in case you are wondering for a low capacity model. Higher ratings (bigger batteries) naturally cost more. The rating depends on your monitor size, computer wattage and how many accessories that you want to run on the UPS. An average system with a 17" display would likely need a $250 unit. A server or a 21" display with several accessories look to spend $350 and maybe even more.

Some UPS's are very sophisticated indeed and the price can go into the thousands but these types are typically not used for home or small business computers. The amount and type of filtering, response time to switch to battery, on line or off line are some of the jargon involved. If you have a generator in your system somewhere this will also effect the type of UPS that you use. Take for example air traffic control at an airport or in the surgery of a hospital. The consequences of a power blackout could get very exciting very quickly in such cases. UPS systems in critical places like these are coordinated with flywheels, backup generators, etc. I even worked at a place once where the electrical service team serviced and tested their backup generator during a Xmas shutdown and when they went to use it during a power outage 2 weeks later it immediately broke down. As they say, stuff happens ... You cant prepare for every eventuality but some precautions are recommended.

I have had (over the years) too many power blackouts, spikes, brownouts to even count - but because I have a UPS I can happily keep on working away. In most cases an unprotected computer will simply turn off without power and then once power has been restored it can be started again. I'm sure that many (maybe even most) of you have experienced weird things happening to your computer after a power failure. This my valued clients can be prevented. At a price of course, but then again it's only money !

Batteries in a UPS do eventually need replacing, but these are typically less than $50 every 3-5 years.

Is it worth spending $250 to protect your valuable investment? I reckon it is. And I have put my money where my mouth is too. I see problems happening every week and am continually going on site to fix problems caused by people not having a UPS protecting their equipment. Just think of the money you will save on consulting time for me to not have to come out !

Any questions pls call. And have you backed up your data today ...