January 2010: HMI2 Operator
Interface Control Console
Introduces Latest Generation Operator Interface For
The Silo Patrol®
Monitor Technologies, LLC
is proud to announce the new HMI2 which
is the latest generation in operator interface for
the SiloPatrol® SE cable-based “smart” sensor
inventory management system. The optional HMI2 features
two sensor networks that provide operator interface
for up to 32 SiloPatrol level sensors. The HMI2 also
contains a universal AC power supply that supports
an input voltage of 100-240V AC.
The multi-functional HMI2 controls the SiloPatrol® SE
SMU “smart” sensors, displays measured and calculated data and performs/displays
system and sensor diagnostic messages. The HMI2 can be programmed
to operate the SMU sensors manually, automatically or allow for both.
The display is back-lit for visibility in low-light conditions and can show data
in English or Metric units including feet, meters, pounds, kilograms, cubic feet,
cubic meters, U.S./British bushels, gallons, liters, tons, and metric tonnes.
The combination of the HMI2 and the SiloPatrol® SE
cable-based bin level sensor provides an intuitive and versatile inventory management
system for a variety of bulk solid, powder, pellet, granular, slurry, and some
liquid applications. Additionally, when needed, auxiliary relay and/or
analog outputs can be incorporated into the system by using the optional Auxiliary
Output Enclosure (AOE).
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
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,
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
Principle of Operation for the TrueCap RF Capacitance Level
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.