All force transducers and load cells are precision mechanical devices, even if their external and sometimes quite robust shape often does not suggest this.

They consist of a steel or aluminum spring body of various designs. The force to be measured deforms the spring body in the elastic range of the stress-strain diagram (Hooke's straight line). This deformation serves as a measured variable for indirect determination of the acting force in the application.

The first factor influencing the measuring accuracy is therefore the spring body itself, as it represents the counterforce to the measuring force. Unfortunately, the external shape of a force transducer as a "clumsy steel or aluminum block or bolt" does not encourage careful handling, especially during installation. It is hard to imagine that any bumps, knocks, nicks or abrasions will lead to a permanent loss of quality that could have a direct impact on the future measurement result. Force transducers that are used as "hinge pins" in crane arms, connecting rods or similar for measurement purposes must always slide smoothly, as otherwise undefined forces can arise that momentarily or permanently falsify the measurement result. During installation, position corrections by hammer blows or other force effects on the force transducer are therefore prohibited.

The second component of a force transducer is a transducer that generates an electrical signal from the mechanical deformation of the spring body. In most cases, very thin foil resistors (strain gages) are used as transducers, which are bonded to specific points on the measuring body and connected to form a Wheatstone bridge. These bonding points are encapsulated with an elastic substance in order to offer the greatest possible protection against mechanical and chemical influences. These encapsulated areas must not be damaged or used to apply force, as this would otherwise destroy the function or lead to measurement inaccuracies and also facilitate the penetration of water, alkalis or other substances within a very short time.

Knowledge of these correlations alone can make a significant contribution to the VELOMAT force transducers achieving a longer service life in practice.

If you have any questions or comments, please do not hesitate to contact us.