Structure And Mode Of Operation; Transducer; Strain Gage Covering Agent - HBM U2B serie Montageanleitung

Structure and mode of operation

4 Structure and mode of operation
4.1

Transducer

The measuring body is a stainless steel loaded member on which strain gages
(SG) are installed. The effect of a force deforms the measuring body, so that
there is strain in places where the strain gages are installed. The SGs are
attached so that four are extended and four are shortened. The strain gages
are wired to form a Wheatstone bridge circuit. The SGs change their ohmic
resistance in proportion to their change in length and so unbalance the Wheat­
stone 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.
4.2

Strain gage covering agent

The force transducers have thin cover plates welded at the base to protect the
SGs. This method provides excellent protection against environmental influ­
ences. These plates are protected by the adapter under normal use. If you
use the U2B without the adapter screwed on, make sure that you never
remove or damage the plates, as this could jeopardize the protective effect.
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A00382_03_YI0_06 HBM: public
U2B