October 2010: Models SFD-2
and SFI Microwave Solids Flow Detectors
Selection
of Options Make Solids Flow Monitors Even More Versatile
From automated systems with pneumatic
lines to gravity chutes and feeders, solids flow monitors
can help to improve process performance. The Model
SFI and SFD-2 line of solids flow detectors from Monitor
Technologies, LLC provide analog or relay outputs to
indicate the flow / no-flow condition of powder and
bulk solids materials in process lines. These units
use microwave Doppler radar technology that makes them
extremely reliable. Their rugged design withstands
the rigors of the installation and process extremes.
They can assist in detecting flow problems, as well
as, enhance the level of automation at a facility like
turning a conveyor on or off. Solids flow detectors
can be used in a variety of applications including
consumer foods (cereal, sugar, cocoa, coffee), feed
milling & grain processing, chemicals & pesticides,
carbon black, coal and more.
A variety of options make these units even more versatile. For instance, a stainless
steel food grade mounting adapter with a choice of process seals is available.
Also, the optional saddle coupling provides a means of mounting the transceiver
without welding a coupling to the process line. Greg DeRudder, Monitor’s
Product Manager mentions, “The variety of available options for the SFI
and SFD-2 can assist in creating a non-intrusive, non-contact flow detection
system that provides added efficiencies to a process.” For more details,
please visit www.monitortech.com or
e-mail monitor@monitortech.com.
For more information, please visit
www.monitortech.com or call 1-800-601-5953 / 1-630-365-9403.
Monitor Technologies LLC, located
in Elburn, Illinois, is a leading manufacturer of level
measurement instrumentation, solids flow indicators,
particle emission monitors and aeration devices for
the worldwide powder and bulk solids markets. The experience
and market knowledge gained over 50 years of business
has earned Monitor a reputation for providing high
quality and reliable product solutions backed with
trusted customer service. For more information please
visit www.monitortech.com.
The TrueCap® Model MK-2
RF Capacitance point level probe is designed to provide a superior
and stable sensitivity threshold making it suitable for a variety
of powder / bulk solids and some liquid or slurry applications.
Advanced features of the Model MK-2 include: > Automatic immunity to material build-up on
the probe by its driven shield design > Push-button calibration > Enhanced temperature compensation > Maximized reliability via smart sensing algorithms
like “self-validating” fail-safe protection > Visible status LED on ordinary location units > Versatility through a variety of configuration
options including: hazardous location version, split architecture
design, quick-connect process connection, stub probe, cable extensions,
solid extensions, Nylon® probes, Ryton® - equiv. probes,
etc.
A practical application for the TrueCap would be to use this level sensor where
a residual material build-up on a different sensor would cause a false material
level indication.
Principle of Operation for the TrueCap RF Capacitance Level
Probe:
The vessel wall and the active probe element establish an impedance reference
between each other when exposed to air which has a dielectric constant of 1.
When materials with a dielectric constant greater than 1 are in close proximity
to the probe, the impedance of the sensing field between the sensor and the vessel
wall will change. Once the amount of change exceeds a threshold that was electronically
determined during the calibration process, an output relay will either be energized
or de-energized depending upon the position of the fail-safe selector on the
probe’s electronic circuit board. A change of as little as .5 pico-farad
is all that is necessary for the probe to sense the presence of material.