Funny thing how things work out time-wise: I had a discussion yesterday on the very topic during re-audit for ISO 9001.
In basic terms, verification in metrology is a very slimmed down calibration: For a calibration, you essentially check every range of your instrument at usually five or more spots within that range in order to determine accurracy of your instrument in each range. For a verification, you do this only at the spot where you intend to measure. So if you were to measure a nominal 7.2V source, you'd compare the reading of your meter with your, say, known good 7.5V reference instead of doing a full calibration of the meter. It doesn't tell you anything about, say, the offset error of your meter, or how big the deviation is at the 1000V range, it just tells you if your meter meets requirements of the one measurement you intend to do. So, in order to determine whether or not your chinese voltage reference meets its specs, you'd check your meter against, say, the well-characterized LTZ1000A you happen to have in your lab. Strictly speaking, you still have to do it as carefully as you would do a real calibration, taking all known effects into account, but it's still much less time-consuming than a full calibration as you check only one single point instead of all possible ranges with five points each. Does this help answer your questions or did I just bring up more questions than answers? best regards, Florian Am Wed, 3 Jun 2020 09:58:59 +0100 schrieb "Dr. David Kirkby" <[email protected]>: > I am trying to work out what the BIPM definition of verification means > > https://jcgm.bipm.org/vim/en/2.44.html > > “ provision of objective evidence that a given item fulfils specified > requirements” > > Let’s assume that I wanted to verify if the voltage reference meets > the Chinese specifications. Would consulting the 3457A manual and > voltage reference specifications, to determine if the meter is good > be considered verification? > > Or does verification only apply to an instrument? For example > comparing the 3457A to a Fluke voltage reference? > > The one sentence definition in VIM leaves me wondering what the > intension of the entry is. > > > > _______________________________________________ volt-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/volt-nuts_lists.febo.com and follow the instructions there.
