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Sensing
the
strain
Robin Shepherdson,
Scale-Tron,
discusses
the importance of
using the right sensor
for silo strain-gauging
and level measurement
applications.
Introduction
There have been many recent developments in measuring
silo inventory by weight, a task that is becoming increasingly
digitised. Sensors bolted onto the silo support structure produce
a measurable voltage that can be converted to digital form and
displayed as a single reading: a series of bar graphs for a number
of vessels or a trend graph for a single silo. This enables a user
to determine the best time for filling, so that the company never
runs out of material and never overfills a silo, which could create
an environmental hazard. It also enables the user to measure each
delivery and detect shortages due to fraud.
Developments in sensor technology
It used to be that strain-gauges had to be welded onto the vessel
legs with a special welder; however, sensors can now be simply
bolted onto the leg or skirt surface. These are compensated to
give neutral output when bolted to structural steel, but many