Structure And Mode Of Operation; Force Transducer Operation; Sg Covering Agent - HBM C15 Bedienungsanleitung

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Structure and mode of operation

5.1

Force transducer operation

The measuring element is a steel loaded member made of steel (for nominal
(rated) forces from 25 kN) or high-strength aluminum (for nominal (rated)
forces up to 10 kN) to which strain gages (SG) are applied. The SGs for each
measuring circuit are installed so that four extend and four shorten when a
force acts on the transducer.
Each strain gage changes its ohmic resistance in proportion to its change in
length and so misaligns the Wheatstone bridge. If bridge excitation voltage is
present, the circuit produces an output signal proportional to the change in re­
sistance and therefore also proportional to the applied force. The SGs are ar­
ranged such that parasitic forces or torques and temperature effects are com­
pensated as much as possible.
5.2

SG covering agent

To protect the SGs, the force transducers have thin cover plates that are
welded on at the top and bottom (steel versions, nominal (rated) forces from
10 kN) or glued (aluminum versions, nominal (rated) forces up to and including
10 kN). This procedure offers the SGs a high level of protection against envi­
ronmental influences.
In order to retain their protective effect, these plates must not be damaged in
any way.
C15
A05091_01_YCI_02 HBM: public
Structure and mode of operation
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