When the lights go out...
- Protecting your computer from unreliable power supply
how unreliable power affects your computer
Your computer, like any machine containing a microprocessor (VCR, microwave etc) relies on a particular level of electrical power.
If the power supply is not reliable (‘spikes’, ‘flickers’, ‘browns out’, ‘cuts out’ etc), then your CPU (Central Processing Unit) cannot do its job.
I once had the dubious experience of seeing someone who had just been through ‘electric shock therapy’ (ECT - electro-convulsive therapy).
Yes, it is still done to people, not just to computers.
This lady couldn’t remember her name, couldn’t stand up and couldn’t speak properly.
Your computer’s central processor can’t function, either, when instead of getting the level of electricity it uses to carry information (the level stated on the wall socket), it gets cut off (often with a ‘spike’), gets non-standard levels of power (‘flickers’, ‘brown-outs’) or sudden jolts of high-level electricity (‘spikes’).
Depending on the level of disruption, afterwards:
- all unsaved work will be gone; you will have to do it again
- any file open at the time can be damaged, even if it has been saved;
you will not be able to use that damaged file, so unless you have a backup copy of this file, you have lost the whole thing
- any program open at the time can be damaged;
it will cause problems for you and for your operating system until it is completely reinstalled from the original disks
- in fact any file or program on any disk in a disk drive connected to the power at that time, can be damaged;
you won't enjoy finding out which ones have been
- your operating system (Windows, Macintosh, Unix, OS/3) is always open when the computer is in use, and any part of that system software can be damaged;
you will have problems with the computer which will be very difficult to track down, until you do a complete clean install of your operating system from the original disks
- if there is an internal fuse in any part of your computer system
(external transformer, monitor, CPU 'box', CD-drive, modem, speakers, printer, scanner),
it can have blown in order to protect the delicate circuitry;
this part of your system will not work again until a qualified computer technician has identified and replaced the specialised fuse
- any part of your computer system (as above) without a fuse may have damage anywhere in its incredibly complex and microscopic electronics;
without an electron microscope and a year in research, even your qualified technician isn't going to be able to trace which tiny, essential piece has been 'fried' by the irregular power;
you then have to replace whole circuit 'boards';
since the price of the processor board is probably most of the cost of the whole unit, it's worth looking around to see if you'll get a better deal replacing the unit itself (modem, printer, CPU box etc.)
- modems are especially at risk, not only during thunderstorms (because a modem is connected to the computer, the power if it's external and the phone lines), but also if they are carted around and plugged into different power outlets in different locations;
if you use a modem, you've probably already seen what low phone-line quality does to your downloads... you really don't want to see what a casual power surge does to its insides (only once, of course)
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What can I do?
I have no doubt that computer-users in the Riverland have a fair idea of what uninterrupted and efficient computer use means to them.
Those of us with laptops thanked God the compact and expensive piece of machinery wasn’t plugged into the ‘mains’ (gives a whole new meaning to ‘mainlining’, doesn’t it?), kissed the battery (carefully, on the outside) and kept on working for a couple of hours.
What you can do (apart from examining the contract between you and your electricity provider) starts with the ‘spike’ and goes as far as having your own backup electricity supply.
It depends on what you want.
I don’t want my computer equipment to be damaged.
Then you need to make sure that your computer, and any peripherals (printer, 'Zip' drive, CD-drive, modem etc.) are always plugged into surge protection.
A good quality surge-protector (and you can get them built into a plugboard) does not allow a damaging level of electricity to pass through.
It contains a semi-conductor, which absorbs any dangerous levels of power, up to a point when it simply burns out (hopefully without damaging the equipment).
When a surge-protector 'burns out', it leaves a gap that separates the power surge from your computer.
Like a fuse, it has died in a good cause, protecting your equipment, and you then need to get another one.
A low quality surge-protector is not a good deal.
It may in fact just melt down into a bit of wiring, allowing anything and everything through to your equipment.
I want to be able to save my work, quit my programs, shut my computer down properly and turn it off, so no software or data can be lost or damaged.
Then (in addition to surge protection) you need a UPS (Uninterruptable Power Supply).
The UPS has a battery which stores energy while the power is on.
If a power cut occurs, the UPS smoothly switches over to providing power off its battery.
A basic UPS battery will give you enough time after the power cuts out to put everything away.
A UPS can also protect you from irregular power, 'flicks' or 'brown-outs', where the power doesn't simply cut out, it goes up and down.
The UPS, set up appropriately, can filter the power to your computer equipment, buffering the computer from the ups and downs of unreliable power supply, so the functional (working, non-damaging) level of current is maintained.
You buy a UPS according to how many amps (ampères, A) of current it can handle and how long (in hours) its battery will last.
UPS are rated in amp hours (Ah).
For more information on Uninterruptable Power Supplies, check your requirements with your qualified computer technician, and then talk to a qualified electrician.
A quick search at the Australian search engine, Anzwers, found the following websites in Australia which offer information about UPS:
Exair
Maxcom
OMCS
Nulec
Netlink
and others under Yahoo's Categories
I need to be able to keep on using my equipment, 24 hours a day.
Then you need a standby generator (e.g. petrol-driven), at a rating which will support howevermuch equipment you want to run.
This is not a small or simple job.
You want guaranteed continuity of power supply, regardless of the behaviour of your contracted power supplier.
And you want it in order to run very sensitive and delicate equipment.
This means that you need to work out, with your qualified computer technician and qualified electrician, what kind of generator and UPS you would need set up, and how you would need them set up, so that:
- the UPS handles the power going up and down
- the UPS switches smoothly over to its battery when the power cuts out
- the generator starts up when the UPS' battery is low
- the UPS and the generator then link smoothly together
- and the generator is kept fuelled
- so power is maintained to your equipment, at the right level, at all times
This article on protection against unreliable power supply also applies to any essential electrical equipment, some of which may not be as vulnerable to data-loss and damage as anything containing a microprocessor, but none of which is much use to us when the lights go out.
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clytie@riverland.net.au
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