The SafePoint® rotary
paddle level switch with a self-validating design detects
and indicates material presence or absence plus it
continuously monitors its own ability to function.
This functional analysis includes verification of overall
electro-mechanical sensor health and reaction to system
input power failure, which makes the SafePoint a truly “fail-safe” level
sensor. The unit provides a relay output signal
condition if a sensor failure occurs or upon loss of
input power. The SafePoint incorporates patented
use of Hall-effect technology, dual outputs to indicate
both material presence and unit health, and microcontroller
technology to continuously protect bulk solids processing
and storage from the consequences of unknown sensor
failure.
The hazardous location model
of the SafePoint is a practical solution for indoor
grain hoppers and bins or other confined storage
areas that may contain high levels of potentially
explosive dust.
Other features of the SafePoint bin level switch include
its rugged construction, twist On/Off cover for bolt
free removal, motor shut-off when paddle becomes impeded
to maximize motor life, and local status indicating
light (except hazardous location model).
For more information, please visit
www.monitortech.com or call 1-800-601-5953 (US/CAN)
or 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, reliable and practical 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.
