Structure And Mode Of Operation; Transducer; Strain Gage Covering Agent - HBM C11 Montageanleitung

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STRUCTURE AND MODE OF OPERATION

5.1

Transducer

The measuring body is a steel loaded member on which strain gages (SG) are installed.
The influence of a force deforms the measuring body, so there is deformation in places
where the strain gages are installed. The SG are attached so that two are extended and
two are shortened. The strain gages are wired to form a Wheatstone bridge circuit. They
change their ohmic resistance in proportion to their change in length and so unbalance
the Wheatstone bridge. If there is an excitation voltage, the circuit produces an output
signal proportional to the change in resistance and thus also proportional to the applied
force. The strain gage arrangement is chosen to compensate, as much as possible, for
parasitic forces and moments (e.g. lateral forces and torques), as well as the effects of
temperature.
5.2

Strain gage covering agent

The force transducers have thin cover plates attached to the base to protect the SGs. In
combination with the integrated cable, the steel versions achieve equipment protection
level IP64. In order to retain the protective effect, these plates must not be removed or
damaged in any way.
C11
STRUCTURE AND MODE OF OPERATION
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