73. Make right choice for surge
By Mark Alberstat
The motherboard on our computer "fried" and we were told it was due to
power surges even though we had a surge protection device on our system.
We took the power bar/surge protector to the vendor and after some
questioning he informed us that it was only good for two power outages.
Seems strange to me. Can you enlighten me, and your other readers, on
Power outages happen, plain and simple. There is little any of us can do
about it, and if you computer is running at the time, it can become
damaged from the sudden shutdown. To prevent this, several companies have
created surge protectors and UPS (Uninterruptible Power Supply) devices.
Most, if not all, home computers should be plugged into one.
A surge protector is, a long bar with a power switch. This bar plugs into
the wall outlet and the computer and other devices plug into it. Surge
protectors guard against power spikes but little else.
There are three basic types of UPS devices: a standby (also known as an
off line), a line interactive and an on line. The cheapest, and most
widely found, is the standby UPS.
All three work on the premise that when the power cuts out, the battery in
the UPS cuts in and gives you time to shut down your computer.
The main difference between the standby and the line interactive is that
the latter monitors the voltage going through the device and can protect
your computer in "brownouts," or times when the power level dips but
doesn't actually end. When the voltage falls too low, the battery backup
takes over. Because of the regulator built into the device, this type of
UPS is thought to last longer, or at least the batteries in it do, than
the standby models that always turn on when the power drops.
The third, and most expensive type of UPS is the on line model. This
model has a large external battery that is constantly being charged. The
computer is plugged into this battery and when the power cuts out, the
battery is the piece of equipment that loses power, not the computer.
Because the battery is in constant use and always being charged, they do
have a finite life and should be checked every few months to see if they
are still holding a charge and to see how long your devices could last on
the battery alone. The battery units on most of these are good for two to
Once you have a UPS installed on your home computer, you are not
completely out of the woods. The length of time the UPS will keep your
equipment running depends on how many items you have plugged in. The more
items, the more draw on the battery and the shorter the interval the
equipment will be able to run. Although many UPS devices have several
plugs on them, you may not want to have your digital camera dock, scanner,
printer and fax machines plugged into it. The main reason for the UPS is
to give you enough time to shut down your computer in an orderly fashion.
It is a good idea to have your monitor plugged into it so you can see what
you are doing when the power fails.
Some UPS devices come with specialized software that can shut down your
computer when it senses a power interruption and also monitors the
battery's strength and charge. Often this software is for the more
sophisticated UPS, however, some of the lower-end ones now come bundled
With your home computer attached to a UPS, the power outages that may
happen this coming storm season will be less of a worry to you.
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Originally published 27 November 2005