How often do I need to make the connection?
Connecting measurement equipment: when and how?

The question of connecting measuring instruments is obviously essential. Instruments can drift (or be damaged), and what was true yesterday may no longer be true today... Since the metrological traceability of measurement results must be guaranteed for each instrument, including over time, it is essential to check the condition of instruments periodically.

Historically, Legal Metrology initiated this practice by establishing calendar periods for each instrument family. While this strategy is understandable when it comes to guaranteeing fair trade, it is more open to criticism when it comes to demonstrating functionality. Indeed, the butcher's scales can drift in either direction (to the advantage of the merchant or the customer), and the risks are thus shared, without being very consequential. What's more, as the periodicity is set by the State, it's the same in...