ENERGYMANAGEMENT BY DARLENE BREMER
“The cost of power quality issues
worldwide is estimated to be as high as
$400 billion a year,” he said.
Some PQ experts don’t agree with
those numbers, but it’s true that energy
consumption and PQ is of great concern
to end-users as they try to increase competitiveness and save as much as possible.
That concern is warranted. According to
the U. S. Energy Information Association
(EIA), total energy consumption is estimated to reach 114.512 quadrillion British
thermal units (Btus) in the United States
by 2035, which is about a 20 percent
increase from current levels.
Data communications, building automation and higher speed transmission
of every kind of data are dependent on
the availability, affordability and quality
of power. Therefore, electrical contractors can seize the opportunity to test and
measure PQ and consumption, and ultimately offer solutions to end-users.
PQ instruments measure the voltage and
current feeding an electrical load, section
of a building or entire facility, according
to Wade Thompson, product specialist
at Fluke Corp., Everett, Wash. PQ can be
measured at different points to identify
the power component that is corrupted
or causing trouble to the load.
“The power fed to loads directly
impacts their health,” he said. “Main-
taining healthy power quality helps avoid
situations such as the slow degradation
of equipment; PLC [programmable
logic controller] resets; the malfunction
of electronics; breaker tripping; and, in
extreme situations, overheating, smoke
Energy instruments also examine
voltage and current but intend to deter-
mine how much is being consumed. That
data can help a facility manager establish
costs based on the energy that depart-
ments, tenants or particular pieces of
equipment actually consume.
“Any energy-conservation program
requires facts, baselines and goals to
determine success,” Thompson said.
Although both PQ and energy instruments measure voltage and current, they
require different resolutions and accura-cies. Energy meters, which compute watts,
volt-amperes, volt-amperes reactive and
power factors, require accuracy. Typically,
they also do not have PQ capabilities.
On the other hand, most PQ meters
measure time periods as short as milliseconds and microseconds, and, although
most of them have the accuracy to measure energy, they are not certified to do so.
“The objective of power quality
meters is to get an idea of the compatibility of the power source to the load being
measured and to look for sags, swells,
transients and harmonics to assess the
quality of the electrical service,” said Ross
Ignall, director of product management
at Dranetz Technologies, Edison, N.J.
PQ and energy instruments also have
a role in building safety.
“Power quality instruments diagnose
problems stemming from an electrical
systems’ loose connections, grounding
and other components, helping to ensure
overall building safety,” Thompson said.
PQ instruments can also be used to
ensure that the power supply and utility
service are operating within designed
parameters, which will help to avoid any
possibility of overheating, overdrawing
of electricity or other safety issues.
“Energy instruments, in general, can
determine whether equipment or circuits are operating within capacity to
avoid overheating,” Ignall said.
For the contractor
Low-cost, high-performance devices
are available to establish, measure and
record PQ in every installation, from residential to heavy industrial applications.
“For the contractor, power quality
monitoring means offering customers a
new value-added service that will drive
revenue and increase customer satisfaction by isolating problems before they
occur,” Forthaus said.
Load studies and other PQ and energy
measurements enable electrical contractors to go beyond data collection and
make recommendations, Thompson said.
“Any contractor interested in building
long-term, service-related relationships
with customers can use load studies to
demonstrate where a facility has infrastructure load or power quality issues
that could affect operational efficiency
or safety,” he said.
There have been real changes to PQ
instruments over the last three years, said
Leah Friberg, global manager of educa-
tion and industry relations, Fluke Corp.
“Models have become more fail-safe
to use and ensure more reliable results,”
Although newer instruments are
easier to use, higher end tools can still be
more complicated and require training.
As more sensitive electronics and
computer-based components enter every
facet of life, more electricity is being
used. The loads themselves may corrupt
power in the way that they operate.
“Power quality will become increasingly more challenging as we create
these more sophisticated loads,” Thompson said.
Got a Problem?
Power quality and energy instruments
AN ESTIMATED 3 PERCENT of every sales dollar in the United States is spent on
solving power quality (PQ) problems, according to Christopher Forthaus, senior
product manager, test division, Ideal Industries Inc., Sycamore, Ill.
BREMER, a freelance writer based in Solomons, Md., contributes frequently to ELECTRICAL
CONTRACTOR. She can be reached at 410.610.7164 and firstname.lastname@example.org. FL