Specifications

Understanding Power Quality
What is Power Quality?
Industry relies on power quality,yet lack of reliable power can lead to substantial problems.
Power quality is,in essence,powering and grounding sensitive electronic equipment in the
manner that is suitable for its operation.Power quality problems arise when there is a differ-
ence between the quality of power supplied and the quality of power required for reliable load
equipment operation.The electronics age has unveiled two apparent truths about power:
• Utilities cannot provide the clean and consistent power that sensitive electronic equipment
demands.
• Computer or communications customers are ultimately responsible for the safe operation
of their equipment.
You may be surprised to learn that while the power supplied by local utility companies is
sufficient to run components such as lights and television sets,it is not suitable for sensitive
electronic equipment such as computers and servers.
What is the Real Impact of Power Quality Problems?
The financial impact of power quality problems can be astronomical.It is estimated that “dirty
power”and associated momentary disturbances in transmission can cost industry in lost pro-
duction and equipment damage between $3 billion and $5 billion per year.
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The real effects of
system downtime,including lost data and business opportunities,can be immeasurable.
According to a survey by the Business Communications Co.,downtime costs are estimated
between $1,000 per hour and more than $78,000 per hour.Some studies raise this estimate
to $500,000 per hour.
On an even more serious note, research has shown that only 43% of businesses suffering a
substantial power disaster ever recover sufficiently to resume business,according to the
National Archives and Records Administration in Washington,DC.
Every data processing professional knows the risk of hardware damage resulting from a major
disaster.But the truth is that everyday dirty power poses a far greater risk to processing systems
because there’s no way to get rid of dirty power without power protection equipment.Power
problems alone account for 45% of computer data loss,according to Contingency Research
Inc.Equipment that utilizes adequate power protection will experience less downtime.
Although this information emphasizes power quality in the United States,foreign power is
generally more erratic and therefore more damaging than that in the U.S.
What are the Causes of Power Problems?
Only 35% of power problems are generated outside the home or office by events such as
lightning,utility grid switching,mis-wiring,etc.Almost all electrical surges or transient volt-
age activity are generated within the home or business.
Sags are the most common disturbance at a typical computer site (72.1%),followed by surges
(15.8%) and spikes (8.1%).Four out of five computer crashes and communications problems
are caused by deep sags and not power outages and blackouts.
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1
Information Week,January 8,1998.
2
Business Communications Co., 1998.
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