I am doing some research into repeatability practices, requirements, etc. There are six subsections to ISO 5725, each pretty expensive. Can anyone either recommend which of those subsections are really beneficial to study about requirements for calibration-related repeatability requirements, or suggest a resource to get hold of any of the important subsections?
Search: G110 - Guidance on Uncertainty Budgets for
Electrical Parameters
I have G110 (and most everything out there). But not ISO 5725. I am trying to nail down some definitive rules regarding the methods to be used for calculating uncertainty contribution from Repeatability. There are a few schools of thought on it, which I really don't want to get into detail here about. ISO 5725 is a reference the GUM directs you to in this matter. Even GUM Supplement 1 (the one that covers various statistical methods), doesn't give clear direction.
Trying not to be too specific on this. I will just say that a couple of the methods give pretty different numbers in M.U. based on sample size. Even in GUM Supplement 1, there is a note about how using one method can give too high numbers and another can give too low numbers, but does not say which is more correct. Seems like the rules are broad enough that you can pick from among legitimate methods, put it in your policy, and defend it.
Send me your email address, and I'll send you original ISO 17025 clauses.