1. Frequent defects in the material and its application

Assembly faults

Once you've chosen and installed your measuring chain, you're often confronted with problems you didn't realize you had. Serious damage, usually visible, is not the most dangerous. For example, an inspection may reveal a cracked glass envelope resulting from rough handling. The same rough handling will not have had any visible consequences on the metal casing of a resistor, which will nonetheless give false readings. From this point of view, it would undoubtedly be preferable to use instruments whose fragility is obvious at first glance, to avoid forgetting certain handling precautions.

In a liquid expansion thermometer, an error may be due to the non-uniformity of the cross-section of the capillary [R 2530] ....