Digital weighing scales

This page covers digital kitchen and bathroom scales. Digital luggage scales follow the same principles of operation.

Summary

There isn't much to go wrong inside digital weighing scales apart from physical problems which should be visible on close inspection. Nevertheless, their principles of operation is interesting, and an understanding will help diagnose any faults which aren't visually obvious.

Principles of operation

A resistive strain gauge.
A bar-type full bridge load cell.
A half-bridge load cell - top.
A half-bridge load cell - bottom.


See Getting Stated with Load Cells.