Author Topic: Kiss Analog butthurt over Dave getting free stuff  (Read 10609 times)

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Offline nctnico

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #50 on: November 24, 2023, 04:42:20 pm »
Don't forget calibration is not just about accuracy of measurements but also means subjecting an instrument to a (limited) functional test.
I would say it's pretty much a full on functional test.
Nope. There is so much going on in modern digital / software driven test equipment that a full functional test is not feasible for a calibration lab. You'll only know if the hardware works and the software up to a basic functional level.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline joeqsmith

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #51 on: November 24, 2023, 06:07:56 pm »
Don't forget calibration is not just about accuracy of measurements but also means subjecting an instrument to a (limited) functional test.
I would say it's pretty much a full on functional test.
Nope. There is so much going on in modern digital / software driven test equipment that a full functional test is not feasible for a calibration lab. You'll only know if the hardware works and the software up to a basic functional level.
If I knew something worked, it would be the end of the discussion.   That word "works" seems to have taken on many meanings.   For an ebay seller it may suggest they plugged in the device and no smoke came out.  To me, in the context of this discussion, it means the instrument meets all the manufactures stated specs.  Calibration is proof of that.   I'm not suggesting that all calibration houses provide the same service. 

I have had a couple of cases dealing with third party cal houses worth mentioning.  In one case, they were using a calibrator that was not up to the task.  Talking with Fluke, they had a system that could do the job but this company did not want to invest the $$$.   Reports are important as the cal house will supply such details.     

Another case we had a third party calibrate a non-working system.  It magically came back in the same non-working condition with a calibration tag on it.  In this case, seems their definition of works was a bit lacking.  This may be what you are running into and you may consider it acceptable.  A common one I have seen is handheld multi-meters where they were returned with a dead battery or blown fuses, but had an updated cal tag on them. 

A company who designs and manufactures their products may be better suited to re-certify them.  You can imagine that they need to verify every product that leaves the factory.  Much of this testing may already be automated.  Customers may have to pay a premium for that service.   

Offline bdunham7

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #52 on: November 24, 2023, 06:55:50 pm »
Nope. There is so much going on in modern digital / software driven test equipment that a full functional test is not feasible for a calibration lab. You'll only know if the hardware works and the software up to a basic functional level.

A well though out OEM calibration and performance test procedure can identify the vast majority of shortcomings without actually measuring a response at each and every possible setting.  However, I wouldn't expect the calibration process to effectively validate the firmware so testing the outcome of every possible software test seems an unreasonable goal.  IOW, if the device has a design flaw, especially in software, then I don't expect calibration to pick it up.
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 

Online zapta

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #53 on: November 24, 2023, 07:13:54 pm »
Eddie has a more democratized and less elitist approach to test equipment and I like it.

My only rant is that both Eddie and Dave seems to hoard test equipment they don't need rather than design and build stuff.
 

Offline nctnico

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #54 on: November 24, 2023, 09:23:54 pm »
Nope. There is so much going on in modern digital / software driven test equipment that a full functional test is not feasible for a calibration lab. You'll only know if the hardware works and the software up to a basic functional level.

A well though out OEM calibration and performance test procedure can identify the vast majority of shortcomings without actually measuring a response at each and every possible setting.  However, I wouldn't expect the calibration process to effectively validate the firmware so testing the outcome of every possible software test seems an unreasonable goal.  IOW, if the device has a design flaw, especially in software, then I don't expect calibration to pick it up.
Which circles back to my original statement: a calibration can also be seen as a limited functional test.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 
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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #55 on: November 24, 2023, 09:42:29 pm »
Don't forget calibration is not just about accuracy of measurements but also means subjecting an instrument to a (limited) functional test.
I would say it's pretty much a full on functional test.  Then again, I am sure we all have some horror stories when it comes to calibration houses.
For a meter it is pretty typical to have at least one test recorded against every range. But more complex instruments such as scopes only have some of their parameters verified (and/or listed as warranted in the specifications), say channel to channel crosstalk for instance being unwarranted and untested. Or bandwidth, warranted, but untested in different voltage ranges.
For the bandwidth you mentioned,  the factory tests all four channels at nine different voltage levels, not one.  Mine is an 8500A
Different scopes, different manufacturers, have different calibration record/limits/requirements. Not surprising at all.

A sticker on a product that says CALIBRATED (even if in date) is the start of assurance, not the end. Taking a blanket approach can leave the end users complacent to the details of what is inferred by "calibration" and what is actually explicit.
 

Offline joeqsmith

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #56 on: November 25, 2023, 02:08:36 am »
Don't forget calibration is not just about accuracy of measurements but also means subjecting an instrument to a (limited) functional test.
I would say it's pretty much a full on functional test.  Then again, I am sure we all have some horror stories when it comes to calibration houses.
For a meter it is pretty typical to have at least one test recorded against every range. But more complex instruments such as scopes only have some of their parameters verified (and/or listed as warranted in the specifications), say channel to channel crosstalk for instance being unwarranted and untested. Or bandwidth, warranted, but untested in different voltage ranges.
For the bandwidth you mentioned,  the factory tests all four channels at nine different voltage levels, not one.  Mine is an 8500A
Different scopes, different manufacturers, have different calibration record/limits/requirements. Not surprising at all.

A sticker on a product that says CALIBRATED (even if in date) is the start of assurance, not the end. Taking a blanket approach can leave the end users complacent to the details of what is inferred by "calibration" and what is actually explicit.

This is one reason why I request reports.  Sure they add to the cost but I can easily tell what tests were performed, what equipment was used to perform those test, when the equipment was calibrated.  Of course, how my equipment performed during each test.   

Like any other job you may contract out, it's not a commodity.  It's good to interview the company you plan to use and make sure they can provide the service you require. 

Offline .RC.

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #57 on: November 27, 2023, 08:07:54 am »
I would say it is understandable he is just upset he cannot keep up with a fella who lives in Australia that spends a good bit of time outdoors where everything tries to kill you.

The insects try to kill you, the birds try to kill you, the wombats, the dingoes, the drop bears and the endless snakes all try to kill you.  Even the trees and plants try to kill you.  Think the water is safe.  Nope, even it tries to kill you.

These companies sending stuff in for reviews, know to send it to a country where everything tries to kill you.



 

Offline Neutrion

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #58 on: November 30, 2023, 02:00:28 pm »
I would say it is understandable he is just upset he cannot keep up with a fella who lives in Australia that spends a good bit of time outdoors where everything tries to kill you.

The insects try to kill you, the birds try to kill you, the wombats, the dingoes, the drop bears and the endless snakes all try to kill you.  Even the trees and plants try to kill you.  Think the water is safe.  Nope, even it tries to kill you.

These companies sending stuff in for reviews, know to send it to a country where everything tries to kill you.

It is a miracle that Dave managed to survive into such a really old age there. I bet he is already above 30.
Probably because he has that big knife which he can use to kill things day and night.
If he would do a video about his way into the office, it would get a 18 years rating. (Because of violence of course.)He is a hero.
 
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Offline schmitt trigger

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #59 on: November 30, 2023, 04:07:45 pm »
Of course! His vehicle’s Roo Bumper has powerful lasers to blind the kangaroos before running them over.
 
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Offline AVGresponding

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #60 on: November 30, 2023, 05:59:02 pm »
Dont forget the cane toads!

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Offline HalFET

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #61 on: November 30, 2023, 11:57:19 pm »
In SMEs I saw it get bypassed, in large corporations with a working quality management system that demands paperwork, and fat chance you're getting an actual calibration certificate or traceable safety test paperwork from these cheaper manufacturers.
Sure, but how much of the test equipment in a large organisation is inside the calibration/quality system? When that sort of system is in place the equipment I would use day to day (from "A" brands) had big stickers reminding the user it was not known to be accurate and outside the calibration chain.

Does a firmware engineer really care about the voltage accuracy of a I2C bus? or just wants to check its roughly correct and the timing between bytes/messages is what was expected? Neither would that have any safety implications on the choice of instrument.

Having ready access to sufficient test equipment is better than waiting for something more than sufficient.
In our case, everything is tracked and calibration is kept up to date, even on the office multimeters that get used maybe five times a year. They don't want to run the risk of someone using an uncalibrated instrument for something critical. The liability cost of having uncalibrated instruments far exceeds the cost of calibration.
I can believe there are some businesses taking that approach to avoid people using uncalibrated equipment for a task which requires it, and the need varies wildly depending on market/regulations. Your situation seems to be the minority, if they provide sufficient equipment and its all calibrated that sounds very well supported and a nice place to work.
Actually, we're volume manufacturing consumer products and penny pinching left and right. But you're not seeing the financial side of this, when you're moving billions of EUR/USD in products each year you want to minimize your liability at the process level. Say there's a fire at a customer premise due to a product, now you have external parties going through your documentation in legal proceedings, the cost of ownership of those uncalibrated instruments is suddenly a whole lot higher in those scenarios because your internal engineering documentation is now at question. Meanwhile, getting a contract in place with the manufacturer to handle the calibration on an on-going basis, having good inventory management, ensuring no uncalibrated instruments can enter the facility through strict procurement processes, and everything that comes along with it becomes pretty cheap in those instances.

Meanwhile, when I was working in a highly specialized field with high budgets, they were penny pinching on calibrations - even though the customer explicitly demanded them.
 

Offline lezginka_kabardinka

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #62 on: December 01, 2023, 12:58:48 am »
Who on earth says “butt hurt”, apart from adolescent Americans? If you want people to take something seriously, refine your articulation.
 

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #63 on: December 01, 2023, 01:19:00 am »
In SMEs I saw it get bypassed, in large corporations with a working quality management system that demands paperwork, and fat chance you're getting an actual calibration certificate or traceable safety test paperwork from these cheaper manufacturers.
Sure, but how much of the test equipment in a large organisation is inside the calibration/quality system? When that sort of system is in place the equipment I would use day to day (from "A" brands) had big stickers reminding the user it was not known to be accurate and outside the calibration chain.

Does a firmware engineer really care about the voltage accuracy of a I2C bus? or just wants to check its roughly correct and the timing between bytes/messages is what was expected? Neither would that have any safety implications on the choice of instrument.

Having ready access to sufficient test equipment is better than waiting for something more than sufficient.
In our case, everything is tracked and calibration is kept up to date, even on the office multimeters that get used maybe five times a year. They don't want to run the risk of someone using an uncalibrated instrument for something critical. The liability cost of having uncalibrated instruments far exceeds the cost of calibration.
I can believe there are some businesses taking that approach to avoid people using uncalibrated equipment for a task which requires it, and the need varies wildly depending on market/regulations. Your situation seems to be the minority, if they provide sufficient equipment and its all calibrated that sounds very well supported and a nice place to work.
Actually, we're volume manufacturing consumer products and penny pinching left and right. But you're not seeing the financial side of this, when you're moving billions of EUR/USD in products each year you want to minimize your liability at the process level. Say there's a fire at a customer premise due to a product, now you have external parties going through your documentation in legal proceedings, the cost of ownership of those uncalibrated instruments is suddenly a whole lot higher in those scenarios because your internal engineering documentation is now at question. Meanwhile, getting a contract in place with the manufacturer to handle the calibration on an on-going basis, having good inventory management, ensuring no uncalibrated instruments can enter the facility through strict procurement processes, and everything that comes along with it becomes pretty cheap in those instances.
Thats jumping to an extreme, all the compliance and product safety work should/needs to be done with calibrated equipment. That work can even be the majority use (in hours of operation) of test equipment with things left on in production and continually used. But as the example above, there are day to day uses in R&D (as separate from manufacturing or compliance/safety) which have no need for any calibration or traceability, just some guidance/informational.

The thread has also discussed how calibration does not mean every measurement is covered, there is significant judgement/consideration required by the person using the equipment to be sure that the calibration covers their particular use. Calibration is needed in context, not just a blanket (and blind) "must calibrate all instruments that can be calibrated".... which you can have done for almost any meter/instrument even the low rent brands such. I've seen measurement tools calibrated for a single parameter within a narrow range, because that was all that was required, rather than the expense of a comprehensive calibration.
 

Offline AVGresponding

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #64 on: December 01, 2023, 04:49:08 pm »
Who on earth says “butt hurt”, apart from adolescent Americans? If you want people to take something seriously, refine your articulation.

Slang mainly stays with the generation it evolved in, though it does diffuse out a bit, and those adolescent Americans are now adults. In context the expresssion is clearly meant to indicate an immature attitude on the part of the subject of the post; a subtle distinction that perhaps escapes a non-native speaker.
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Offline CatalinaWOW

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #65 on: December 01, 2023, 05:20:35 pm »
Another reason that the big corporations stick with the big name suppliers is that they don't pay list price.  I got a brief insight into this one year when I found that my company got a major (more than 25%) kickback of total annual purchases as long as those purchases exceeded some 7 or 8 digit number.  I have no idea if or how that kickback was allocated among the business units, or how the many tax implications were handled.  Perhaps something in those unknowns made it still more attractive.

I know that the price differential between the good, but second tier folks is larger than the number mentioned, but it adds to the other factors mentioned previously.
 

Offline mendip_discovery

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #66 on: December 01, 2023, 07:08:06 pm »
I know from experience that if you spend lots the sales team can offer you better discounts. Customers willing to spend are good for sales.

On the comment about calibration, labs often can only test the elements that make the kit work. But testing the functions as a whole is a bit of a pain unless you have a known working example of what it needs to be tested on and a known failed example. This is not helped by manufacturers that keep things hidden or no manual mode so the manufacturer is where you have to go to get it calibrated fully, or even adjusted.
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Offline HalFET

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #67 on: December 01, 2023, 11:20:11 pm »
Thats jumping to an extreme, all the compliance and product safety work should/needs to be done with calibrated equipment. That work can even be the majority use (in hours of operation) of test equipment with things left on in production and continually used. But as the example above, there are day to day uses in R&D (as separate from manufacturing or compliance/safety) which have no need for any calibration or traceability, just some guidance/informational.

The thread has also discussed how calibration does not mean every measurement is covered, there is significant judgement/consideration required by the person using the equipment to be sure that the calibration covers their particular use. Calibration is needed in context, not just a blanket (and blind) "must calibrate all instruments that can be calibrated".... which you can have done for almost any meter/instrument even the low rent brands such. I've seen measurement tools calibrated for a single parameter within a narrow range, because that was all that was required, rather than the expense of a comprehensive calibration.
And where do you draw the line on product safety? Where does the accredited body draw the line? Where does the legal system draw the line? It's easy to make such statements online, but the reality is that in practice it can get very blurry. And that's without considering the cost of having to do product recalls, secondary inspections after you failed an inspection round, or the cost of having a single injured person. So no, it's really just easier and cheaper to keep everything calibrated as a large company, then there's never any discussion. And as many folks above suggested, as a large corporation you get "fleet contracts" and you ain't paying the sticker price. So yes, it's actually really just easier and cheaper to go with this approach once you get past a certain size.
 

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #68 on: December 02, 2023, 03:14:17 am »
Thats jumping to an extreme, all the compliance and product safety work should/needs to be done with calibrated equipment. That work can even be the majority use (in hours of operation) of test equipment with things left on in production and continually used. But as the example above, there are day to day uses in R&D (as separate from manufacturing or compliance/safety) which have no need for any calibration or traceability, just some guidance/informational.

The thread has also discussed how calibration does not mean every measurement is covered, there is significant judgement/consideration required by the person using the equipment to be sure that the calibration covers their particular use. Calibration is needed in context, not just a blanket (and blind) "must calibrate all instruments that can be calibrated".... which you can have done for almost any meter/instrument even the low rent brands such. I've seen measurement tools calibrated for a single parameter within a narrow range, because that was all that was required, rather than the expense of a comprehensive calibration.
And where do you draw the line on product safety? Where does the accredited body draw the line? Where does the legal system draw the line? It's easy to make such statements online, but the reality is that in practice it can get very blurry. And that's without considering the cost of having to do product recalls, secondary inspections after you failed an inspection round, or the cost of having a single injured person. So no, it's really just easier and cheaper to keep everything calibrated as a large company, then there's never any discussion.
Where have I said to use uncalibrated equipment for compliance/documentation? There are many tasks within R&D (and even in manufacturing) where there is no impact on safety or compliance, indication only. There should be no blurry for the experienced/qualified people doing such work, they should be educated well enough to be able to confidently identify what needs calibrated devices, and what the calibrations should be (not just a sticker on the front).

Gong hard on calibrating everything just in case is one way to go, it's not the best/only way to go in every situation. You're imagining some world where policy eliminates thought, which I will suggest is likely more dangerous (through people not thinking through what calibration means and applies to) than putting decision making with trustworthy people.
 

Offline HalFET

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #69 on: December 02, 2023, 08:53:19 am »
Where have I said to use uncalibrated equipment for compliance/documentation? There are many tasks within R&D (and even in manufacturing) where there is no impact on safety or compliance, indication only. There should be no blurry for the experienced/qualified people doing such work, they should be educated well enough to be able to confidently identify what needs calibrated devices, and what the calibrations should be (not just a sticker on the front).

Gong hard on calibrating everything just in case is one way to go, it's not the best/only way to go in every situation. You're imagining some world where policy eliminates thought, which I will suggest is likely more dangerous (through people not thinking through what calibration means and applies to) than putting decision making with trustworthy people.

Ok, you do a quick measurement, now you write an e-mail with the results, a colleague quickly copies something from it for some design documentation, congratulations you just have data from an uncalibrated instrument in your design documentation. So yes, it really can get quite fuzzy because people are imperfect and make small mistakes. So it's a black and white issue from a quality manager's point of view, uncalibrated instruments have no place on the work floor. And I can perfectly understand why they're doing it, the laissez-faire approach to handling instrument tracking and calibration has filled up a few graveyards over the years. This is literally the point behind quality systems, it prevents small fuck ups from becoming big fuck ups with mindless procedures to catch mistakes that'd get glanced over otherwise. And yes, it's annoying sometimes, it can be dreadful to deal with, but if you're going to do something like stick an electric heater in a plastic enclosure you damn well want those sort of processes to be in place.

And as to, "it's fine in R&D", it really isn't. I work in R&D, if something weird happens in the field it's not uncommon for us to go on location to figure out what went wrong. Having to second guess your equipment there just ain't worth the potential cost savings.
 

Offline AVGresponding

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #70 on: December 02, 2023, 09:04:11 am »
Where have I said to use uncalibrated equipment for compliance/documentation? There are many tasks within R&D (and even in manufacturing) where there is no impact on safety or compliance, indication only. There should be no blurry for the experienced/qualified people doing such work, they should be educated well enough to be able to confidently identify what needs calibrated devices, and what the calibrations should be (not just a sticker on the front).

Gong hard on calibrating everything just in case is one way to go, it's not the best/only way to go in every situation. You're imagining some world where policy eliminates thought, which I will suggest is likely more dangerous (through people not thinking through what calibration means and applies to) than putting decision making with trustworthy people.

Ok, you do a quick measurement, now you write an e-mail with the results, a colleague quickly copies something from it for some design documentation, congratulations you just have data from an uncalibrated instrument in your design documentation. So yes, it really can get quite fuzzy because people are imperfect and make small mistakes. So it's a black and white issue from a quality manager's point of view, uncalibrated instruments have no place on the work floor. And I can perfectly understand why they're doing it, the laissez-faire approach to handling instrument tracking and calibration has filled up a few graveyards over the years. This is literally the point behind quality systems, it prevents small fuck ups from becoming big fuck ups with mindless procedures to catch mistakes that'd get glanced over otherwise. And yes, it's annoying sometimes, it can be dreadful to deal with, but if you're going to do something like stick an electric heater in a plastic enclosure you damn well want those sort of processes to be in place.

And as to, "it's fine in R&D", it really isn't. I work in R&D, if something weird happens in the field it's not uncommon for us to go on location to figure out what went wrong. Having to second guess your equipment there just ain't worth the potential cost savings.

Unthinkingly and unquestioningly trusting the reading on any piece of TE just because of a cal sticker and a brand-name is also not a sensible standpoint. Without knowledge of what a sensible reading might be, in both normal and fault conditions, and why, it's just a box-ticking exercise.

A cal sticker on a premium brand doesn't guarantee accurate results, it just indicates that reasonable steps were taken to try and ensure them.
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Offline mendip_discovery

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #71 on: December 02, 2023, 02:07:26 pm »
A cal sticker on a premium brand doesn't guarantee accurate results, it just indicates that reasonable steps were taken to try and ensure them.[/color][/font][/b]
95% probability with luck.

I often suggest customers keep a standard or two they can keep around to check the kit.

With scales it a weight, the logic being it's a simple item and means you check regularly that it's still ok. It's a bit like having a resistor or a simple voltage reference about.
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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #72 on: December 02, 2023, 11:06:02 pm »
Where have I said to use uncalibrated equipment for compliance/documentation? There are many tasks within R&D (and even in manufacturing) where there is no impact on safety or compliance, indication only. There should be no blurry for the experienced/qualified people doing such work, they should be educated well enough to be able to confidently identify what needs calibrated devices, and what the calibrations should be (not just a sticker on the front).

Gong hard on calibrating everything just in case is one way to go, it's not the best/only way to go in every situation. You're imagining some world where policy eliminates thought, which I will suggest is likely more dangerous (through people not thinking through what calibration means and applies to) than putting decision making with trustworthy people.
Ok, you do a quick measurement, now you write an e-mail with the results, a colleague quickly copies something from it for some design documentation, congratulations you just have data from an uncalibrated instrument in your design documentation.
For systems I worked in, if there is documentation which requires calibration then the calibration dates+serials/identifiers are recorded against the data. Are you suggesting a quality system that assumes all items are suitable and calibrated but the chain is not auditable because the result is not linked back through traceable calibrations?

The entire point of traceable calibration is that if some discrepancy is found, every item in the chain can be checked, and resultant data produced can be marked as questionable until resolved. That should not change regardless of the percentage of calibrated equipment in circulation.
 

Offline HalFET

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #73 on: December 02, 2023, 11:20:04 pm »
Unthinkingly and unquestioningly trusting the reading on any piece of TE just because of a cal sticker and a brand-name is also not a sensible standpoint. Without knowledge of what a sensible reading might be, in both normal and fault conditions, and why, it's just a box-ticking exercise.

A cal sticker on a premium brand doesn't guarantee accurate results, it just indicates that reasonable steps were taken to try and ensure them.


Come and see, come and see, we've found another person who doesn't understand the point of calibrations! If you get an odd reading on a calibrated instrument, you have a pretty good chance that what you're measuring is the thing acting up, and not the meter. Meanwhile, if I'm working with an uncalibrated instrument I quite literally have to assume that the instrument could be the thing that's acting up, and I have to pull out a second one to get some degree of certainty. And with a calibrated instrument you can, within reason, assume that the quantity you're measuring won't deviate more than a certain percentage from the actual measured quantity, which means you can actually compare measurements from various instruments over time and have a pretty good idea about what's your measurement error and what's the actual effect you're trying to measure. If you do not understand the value of that when you're debugging or designing something, then I'm at a loss for words, it's a major time and effort saver, and as a large company it's the responsible option.

For systems I worked in, if there is documentation which requires calibration then the calibration dates+serials/identifiers are recorded against the data. Are you suggesting a quality system that assumes all items are suitable and calibrated but the chain is not auditable because the result is not linked back through traceable calibrations?

The entire point of traceable calibration is that if some discrepancy is found, every item in the chain can be checked, and resultant data produced can be marked as questionable until resolved. That should not change regardless of the percentage of calibrated equipment in circulation.
Are you a dunce, or is risk mitigation really such a foreign concept to you?
 

Offline bdunham7

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Re: Kiss Analog butthurt over Dave getting free stuff
« Reply #74 on: December 03, 2023, 01:03:28 am »
Meanwhile, if I'm working with an uncalibrated instrument I quite literally have to assume that the instrument could be the thing that's acting up

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.

Personally I think the key here is generally to not use other people's instruments and to not let them use yours.  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.
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 
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