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Power Surges and Spikes


What are They?

Power surges are an increase in the voltage that powers
electrical equipment. Surges often go unnoticed, often
lasting only 1/20th of a second, but they are much more common and
destructive than you might think. According to recent
studies, electrical equipment is constantly experiencing surges of
varying power. Some of them can be absorbed by a power supply
while others can only be handled by a quality surge
suppressor. The most destructive power surges will wipe out
anything that gets in their way!

Where do they come from ?

In this power-hungry computer age, utility power systems are
often pushed beyond their capacity, resulting in unstable,
unreliable power for consumers. Overburdened power grids can
generate powerful surges as they switch between sources or generate
“rolling surges” when power is momentarily disrupted. Local
sources can also generate surges (such as a motor starting, or a
fuse blowing out).

What about Lightning?

Lightning can generate a spectacular surge along any conductive
line to destroy everything in its path. No matter what
manufacturers may claim, no surge suppressor in the world can
survive a direct lightning strike.
However, with quality
equipment the surge suppressor will take the hit – ending up melted
– but the equipment it protects will not be affected.

Choosing the Right Level of Protection

Joule Ratings: The bigger, the better! Joule
ratings measure a surge suppressors ability to absorb surges.

  • 200 Joules: Basic Protection
  • 400 Joules: Good Protection
  • 600+ Joules: Excellent Protection

Surge Amp Ratings: Higher ratings offer more
protection. Amp levels are another important factor in
determining surge strength. Look for the highest amp
protection levels available.

UL 1449 Voltage Let-Through Ratings: Underwriter
Laboratories tests each surge suppressor and rates them according
to the amount of voltage they let-through to connected
equipment. The lower the let-through voltage, the better the
surge suppressor is. UL established the 330 volt let-through
as the benchmark because lower ratings added no real benefits to
equipment protection, while surge components, forced to work
harder, failed prematurely. Be wary of manufacturers claiming
lower let-through ratings.