Calibration certificates are not magic tokens that shield you from the possibility that your instrument may malfunction. Your test instrument is always part of the circuit and you always have to consider that the instrument may have a fresh or previously unknown defect. For a concrete example, if I observed an unexpected reading using my Fluke 27 (obviously quite old) I would assess the probability of the meter having a problem as extremely low, the possibilty of an issue with the test leads or setup as worth a look and the likeliehood that the anomalous reading is, in fact, correct as pretty high. An 11-month old calibration certficiate stuck on the back wouldn't move the needle on my expectations. Now I have the means to check it myself, something I think every critical use should require.
Of course, but if the instrument literally hasn't been checked in years, as if often the case with "that office multimeter in the drawer" in most companies, you should honestly automatically get a second one and check if the measurement is anywhere close. If you calibrate all instruments on a yearly basis, you at least have some certainty that it passed a fairly thorough functionality check at some point in the last year.
Personally I think the key here is generally to not use other people's instruments and to not let them use yours.
I have yet to see a place where everyone gets their own equipment.
That freshly calibrated $5K LCR meter might have just been used by some idiot to test a charged reservoir capacitor in an SMPS. The sticker won't protect it.
But that doesn't change the fact that having mystery instruments that are never checked around the office is a great way to make mistakes, and a good cal lab will in fact make sure that everything is within spec over the entire range of each instrument that passes through their hands. So they have a tendency to catch things that you might not find as easily.
Risk of what? Are you calibrating everything just so you can always assume the any measurement made in your facility is made by an in-calibration instrument? I suppose that could mitigate certain risks. But part of any calibration program is remediation--when an instrument comes back with an OOT (out of tolerance) report. If you have 100 bench meters in your facility and you don't keep track of who measured what with which one, just one of them coming back OOT means everything you've done for the past year is suspect.
Various fuck ups that happen in industrial environments: Say Josh from the office takes their multimeter to the production line to check out the first batch of a new product and leaves it there, one of the guys in manufacturing takes it and starts using it to do verification measurements on the products that were rejected by the automated system. If that meter was calibrated and the guy in manufacturing does that, whoopsie but not too big of a concern really, remember everyone why you shouldn't do that. Now repeat that with an uncalibrated meter, and you were checking if a heating element was within spec, congrats massive financial consequences since you now get to recall products. So yes, it's really just part of risk mitigation, I don't get why you guys seem to think it must be some sort of absolute defence against measurement fuck ups, but it's part of a multi-layered risk mitigation strategy.
As others have said, it is usually a matter of risk mitigation and uncertainty tracking.
In my experience, the decision of implementing a company-wide mandatory calibration of equipment depends a lot on the size of the facilty, as larger environments will have people with a wide variety of expertise and inclination to follow procedure. In smaller facilities there is much more control over the user base of such equipment, thus some leeway tends to exist. In these cases the risk mitigation is prevalent.
Also, uncalibrated equipment has no place at any station or bench that performs parameter characterization that will be published (either internally or externally). In this case the uncertainty tracking is prevalent. On the other stations it might be a mixed bag due to practicality and cost.
One aspect that tends to fall between the two scenarios above is when a unit returned from the field needs to be checked (failure analysis). This usually is tested first at the general station for evaluation and might get back to the fully characterized station depending on the severity, size of customer, etc. This is where having calibration across the board can be beneficial and mitigate risk.
Taking back to the original subject of the thread, in any professional circumstance the calibration will be needed at a certain point and some types of equipment will require a complete manufacturer's calibration amd evaluation. So, it is still naïve to imagine this carries no value or does not contribute to the retail price.
Exactly, we have 1500+ people on site frequently at the same time from all walks of life, so you can't assume knowledge or expertise from everyone on every single topic. And there's honestly no way to keep tools contained to particular areas, folks will just forget or misplace things, and not everyone who uses the tool will be able to identify everything that could be wrong with it. It also means we don't need two separate inventory systems for instruments, which apparently also makes it less of a headache to handle for some of the administrative departments.
I can't imagine taking my linear adjustable power supply with analog meters in to make sure it is in calibration.
Yep, it's sometimes ridiculous, but the nice thing is that they also tend to do things like replace oxidized terminals while they're in for calibration.
Are you an arse, or is common courtesy really such a foreign concept to you?
If you can't make your points without resorting to insults, I put it to you that it is your calibration that is at fault.
Common courtesy is also not repeating yourself twenty times while failing to understand that the economics of such operations differ greatly for large enterprises when compared to your home lab or a company with ten people.
That's when you have a choice. When you work in a regulated industry, you are just required to do it, you don't have a say, and it turns out fine (if expensive).
I worked in the medical field at two different companies, both were wild and loose with it compared to a consumer goods manufacturer, which is honestly quite surprising if you think about it. Though the latter probably learned about instrument calibration and maintenance practices things through expensive lessons.
But yeah, to get back to the original topic, if you have enough cash at hand in a professional environment, purchasing the more expensive instrument is often surprisingly economical. You just got to be sure you're doing it for the right reasons and don't have idiots ordering expensive things for the sake of prestige, and I've run into the latter type of colleague multiple times as well.
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