POWER January 2011 - 16

plans were able to allow for transformer
replacement before the occurrence of a
catastrophic failure. Exelon's experience,
as well as that of other power utilities
across the grid, has spawned a report by
the Institute of Nuclear Power Operations
(INPO) of Atlanta, Georgia, that
recommends that performance monitoring
and trending be applied to all
large transformers in order to establish
a baseline for transformer maintenance
strategies.
In the case of dissolved gas monitoring,
INPO recommends that online
continuous monitoring be used.
That conclusion has been echoed by
the Electric Power Research Institute,
which has been funding research on online
transformer monitoring since the
early 1990s.
Extending Exelon's Online
Monitoring Programs
Exelon's positive experience with online
transformer oil monitoring has caused
the company to make remote online monitoring
one of the main foundations of
its maintenance effort, and the company
has begun to explore the monitoring of
its other distribution assets. For example,
the company has begun installing
online monitors on its transformer bushings
that will take measurements and be
able to detect the presence of dangerous
conditions without first requiring that
the system be taken offline.
These experiences at Exelon show
that online monitoring enables improvements
in reliability and safety and has a
proven return on investment as well.
-Contributed by Ismael Rivera, transformer
and switchyard system manager
for Exelon Corp.
Selecting a Specialty
Accumulator
Sudden bumps and shocks are great fun
when you are off-roading or are riding on
a rollercoaster. But when you are operating
a piece of equipment, you want it to
be running as smoothly as a Cadillac rolling
down the interstate. Sudden changes
in pressure produce vibration, cavitation,
and water hammer and generally lower the
lifespan and reliability of fluid systems.
The basic problem with pressurized
fluid systems is that liquids are
not compressible. There will always be
changes in pressure and flow brought
about by such things as the opening
and closing of valves, restrictions in
piping, or the action of a reciprocating
or rotary pump. Because those pressure
January 2011 | POWER
 Long life (hardened steel) coal
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 Standard manual operation, or
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After
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(800)-614-1259 www.combustiontc.com
CIRCLE 7 ON READER SERVICE CARD
15
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POWER January 2011

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