Tecsis F9304, Руководство по эксплуатации, Страница: 18 / 28

Betriebsanleitung/Operating manual F9304
18 BD_BE 9005 a www.tecsis.de
2 Scope of delivery
Clamp-on load cell, operating manual
3 Deployment areas and usage instructions
The load cells in model series F9304 are designed for retrofitting of
overload protection units on existing cranes and hoists. The function
of the clamp-on load cell is robust and accurate monitoring of rope
forces. The premise for using of the load cell is a fixed point of the
rope, because the measurement is made on unmoved rope. The load
cells are suitable for harsh environmental conditions and tough
operational demands. They are maintenance free and can also be
installed in locations that are difficult to access. As precision
measuring devices, the load cells must be handled with care during
transportation and assembly. Shocks (e.g. colliding with a hard
surface) can also cause unexpected overloading during measuring
operation, causing permanent damage.
The limits for the permitted mechanical, thermal and electrical
loads are listed in the “technical data”. These must be complied
with.
4 Design and method of operation
4.1 Measuring element
Innovative load cell manufacturing methods using the strain gauge
principle have recently been developed. Etched wire strain gauges are
not used in this case. The entire Wheatstone bridge with the
necessary equalisation resistances and temperature compensation is
realised using a thin-film method on a metallic, pot-shaped body. The
bridge circuitry of the sensors is actively calibrated during the
manufacturing process using laser calibration. This thin-film sensor
can now be inserted into an appropriately shaped measuring spring
with the aid of a laser welding method.The welded-in thin-film sensor
and the optional electronics are sealed against moisture and dust.