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INSTRUMENTATION

the machinery that makes this stuff has
constantly gotten tighter and tighter and
tighter. The tolerances have tightened up,
so that you get more throughput out of
the machinery. You get your money back
faster, the ROI. The gap measurements
that you're making in the cutting and
sewing machinery are becoming tighter
and tighter also. And these are tied directly to quality.
In this case, as an example, if we take
a typical carding machine and want it
to run in optimal performance, the tolerances, if they can be maintained, will
produce the best throughput of the material from the machine, at the highest quality. in this particular case, considering the
wireless functionality, sometimes you've
got to make high tolerance gap
measurements and you just
can't get in there.
It used to present an impossible situation, where you
can't make the measurement
because it's dangerous to address the point of measurement. You can't get fingers in
there. You can get a probe tip
ripped off, or you can't get a
tool in there because it would
snag on a rotating surface and
tear the tool out of your hand.
There's a variety of measurements that are out there like
this, where you want to make
a high tolerance measurement
and you just can't get ordinary tools in
there.
Sometimes, the measurement needs to
be in a hazardous environment such as
exposed moving machinery or poor airquality environments. It can be perhaps a
type of environment that the traditional
measurement tools are not suited for. The
surface can be magnetized, or it can be an
uneven surface. So, all those things may
make the options of how else you would
be able to measure it very limited. In the
case of the carding machine, ripping wires
in the machines,
In this application, the traditional way
of measuring these things, other than
shutting the machines down on regular
intervals to take measurements, was with
Eddy current probes. Well, because you

have spaces between these ripping wires,
the Eddy current will not flow into the
surface and make a precise measurement.
Whereas capacitance being electrodynamic in nature with an electric field-
rather than a magnetic field-allows the
wireless capacitive-gap sensor to make
the measurement.

operational tolerances within a process
allows for a feedback loop to adjust that
tolerance on the fly. This improves performance, reduces wear, vibration, and
thermal loads, while increasing system
operational lifetime and reliability. A
wireless capacitive-gap sensor gives engineers the ability to create such systems.

Predictive maintenance

Scaling becomes possible

Another example of an application where
clearances are critical is in gas-turbine
engines for power generation. In rotating
turbine applications there is an output
mechanism called a vane, and there's no
easy way to make the measurement of the
vane position. A wireless capacitive-gap
sensor could measure that position.

Micron-level measurement in difficult
to access environments was just something commonly accepted that you just
couldn't do. In many other industrial
applications besides carding machines,
where you need to deploy dozens-if not
hundreds-of these sensors, not only was
it cost-prohibitive, but you just couldn't
reliably get the resolution you
needed to make it even worthwhile. Self-contained wireless
probes using a capacitance
based noncontact method,
makes real-time measurement
taking feasible with miniature,
self-contained capacitance
probes to make micron level
measurements.

Looking forward

A key enabler here is predictive maintenance, where it may be very difficult to
put a sensor into critical locations in a
system, in this case-to determine a valve
position. This applies to a multitude of
applications, because once machinery
has the ability to notice out of tolerance
condition poor performance, it can trigger
a preventive maintenance action.
Issues like bearing wear on rotating
mechanisms, where you have a bearing
and there are two surfaces on the bearing, you can't hook a wire to it because
it's going to get wrapped around the axle.
A wireless noncontact sensor is ideal for
such situations.
The ability for a machine to look inside of itself while operating saves both
money and effort. Knowing in real-time

Advanced remote wireless
sensing is a force-enabler for
next-generation automation
functionality, as it enables
the system to maintain operational tolerances more precisely and with no downtime. Increased
precision in an electromechanical system
delivers multiple advantages, each with
their own cascade of peripheral benefits.
Smoother, faster, safer, and more reliable industrial systems run cooler, have
less downtime, operate more efficiently, and are more reliable, as predictive
maintenance significantly reduces the
chances of catastrophic failure in any
operational process. Wireless capacitivegap sensor technology and its application
can help create these advanced "selfaware" solutions.
RELATED ARTICLES:

"Bringing Mechanical Probing Out of the
Stone Age", www.evaluationengineering.
com/13000162

AUGUST 2020 EVALUATIONENGINEERING.COM

http://www.evaluationengineering.com/13000162 http://www.EVALUATIONENGINEERING.COM

Evaulation_Engineering_August_2020

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