Most technology depends on a clean, uninterrupted supply of
Unfortunately, inconsistencies in your electrical supply or a sudden
complete loss of power can cause major damage to computer systems and
other sensitive equipment. This month we investigate power problems and
the devices that are essential for protecting your technology
Electrical supply is subjected to ‘brownouts’, surges and even complete
outages. ‘Brownouts’ are momentary slumps in supply, to a level under
100 volts. They are normally caused by ‘heavy use’ devices (e.g. motors,
compressors, air conditioners and laser printers) being turned on,
creating a momentary drain on the power supply. Brownouts can affect a
computer even if the voltage dip cannot be ‘seen’ (e.g. the lights in
the room dimming). And if they don’t crash your PC, they can cause
stresses that can shorten the life of its components.
Surges of power often follow brownouts as the power rebounds back to
normal, and can have similar effects caused by too much voltage.
Complete outages are most common in suburban areas where lines are hung
on poles that are exposed to lightening.
Surge/power filters or protectors
are designed to ‘fail’ and cut the offending power supply before it
damages your equipment. A direct lightning strike or similar condition
will destroy any surge/power filter, but it will indicate that it has
lost protection and may still have some protection in reserve until it
can be replaced. A surge/power filter is designed to ‘self-sacrifice’
itself, and is low cost compared to some other alternatives.
An Uninterruptible Power Supply (UPS) sits between your
power outlet and your electronic device,
providing backup power from its batteries when the mains supply fails.
This gives you time to safely save open files and initiate the
computer’s shutdown process.
Additionally, most UPS’ regulate the power that comes from the wall,
eliminating sags, spikes, noise, and other electrical interference that
can damage equipment and data or interrupt operations.
If I have a UPS, do I need surge protection?
Yes - International standards don’t require UPS’ to have surge
protection, so they don’t have a high level of protection as this would
increase their cost and make them uncompetitive. They are designed to
handle the end of a major surge, not the whole surge itself, so the UPS
device itself also needs adequate protection from surges. It’s much
cheaper to replace your failed surge protector than your fried UPS.
How long can things run on a UPS during a blackout?
Well, there is no standard answer, as UPS solutions are available to
support devices from anywhere from five minutes to two days. There are
also several types of UPS, namely Standby, Line-interactive,
and On-line, which have different features (and associated
costs). Typically, you should plan on enough run time to allow you to
save any open files and safely shutdown your system.
In many cases, power protection can be justified by looking at the
consequences of not having it. Several hours of professional work can be
lost with just one brownout, due to a computer crashing before the work
can be saved to disk. The consequences can be even more devastating if
the power interruption physically damages the saved, historical data on
the computer’s disk. This can cause a business to suffer expensive
setbacks in terms of time and disruption, even if the data can be
restored from a recent backup.
Talk to your local Computer Troubleshooter about how power protection
can help to prevent you from losing valuable time and money.