Testing random meters for accuracy with DIY resistance tester.

I made a simple resistance tester for meters that tests them with 1, 10, 100, 1K, 10K, 100K and 1Mohm 1% resistors. I chose 0.5W resistors for the lower ranges and a high voltage resistor for the 1Mohm range to allow for checking insulation testers.
If you want to make a similar tester for electrical installation meters the two most useful resistor values are 1 ohm and 1 megohm. The 1M resistor will need to be rated for 1kV or more for insulation testers that can test at that voltage. It's a good way to check a meter is functioning correctly.
The only time I've seen electrical installation test meters go out of calibration is when they've been abused. Usually involving applying the probes to a live supply and then attempting to do a resistance test on it despite the warning light being lit. Modern meters try to be idiot proof by preventing the test being done, but ironically they are less reliable because of the more complicated circuitry.
The routine calibration thing appeared at the same time as the Part P protection racket was pushed for by organisations who make a LOT of money from it. It's part of the same detached paperwork industry that brought us the five-day electricians certificate. (The same reason meters now need to be idiot proof.)
It's reassuring to see that my old American-made Fluke from around the early 1990's is still reading accurately.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
www.bigclive.com/coffee.htm
This also keeps the channel independent of KZbin's advertising algorithms allowing it to be a bit more dangerous and naughty.

[@DigitalYojimbo]

Can we get a teardown of the robin dmm; so that we may see what went wrong ?

[@Storm-tg8rx]

Friend: "What did you do today?"

[@LazerLord10]

Hmm... This gives me something to do with the 0.01% 5K resistors that were in the junk bin at work. (also, those things were $7 apiece, and they're 0603!)

[@PavelGrund]

Suggestion: Instead of using absolutely accurate 100k resistor (which you may not have on hand) in that gadget you can use two parallel 200k or four 100k (two parallel sets of two resistors in series) and match them so they give you bang on value instead of sticker, that 100k is actually 99,69 kΩ.

[@timg375]

I love my trusty Fluke meter. Got it free from College as the were getting new ones so the department chair gave the older ones to us Electrical students.

[@christopher88719]

Big Clive, you are so right when you say you just know when your meter 'is giving rogue readings'. You kinda develop a gut intuition on things after you been around meters long enough.

[@656hookemhorns]

Who else was waiting with anticipation for the cheapy yellow meter?

[@jonathanellis3169]

Thank you Big Clive, for the little mention about the UT210E's Clamp based DC ammeter. Just been trying to find a meter to help me find a slow drain on a car, and having looked at many reviews of similarly priced and more expensive meters I think I'll be buying that one.

[@nutbastard]

I'm currently watching this video, and I don't know if I have the capacity to resist finishing it. You really lead the way, and you're always opening gates for young minds who might have reluctance towards being induced to appreciate these kinds of fields. I love how you charge in without any filter and we're lucky to have you on a platform that presents no interference in your content. I'm always alternately oscillating between you and AvE, and it's nice to have this content directly available.

[@davidprice2861]

Totally agree regarding Uni-T meter, very useful, very accurate and nifty.

[@reddog694uk]

Having researched the cost of good decade boxes, i have resigned myself that a design such as yours is currently the only way forward for non-professionals like myself and i like your design very much. Well Done !!

[@lwilton]

Considering that 50 years ago your normal serviceman's analog meter was typically 3% for a good meter and 5% or worse for a cheap meter, having just about anything being within 1% over the whole range is really pretty darn impressive.

[@dj_paultuk7052]

I have a very similar Fluke to yours, i have the 77. Which was given to me at the end of my MoD apprenticeship 28yrs ago. It still works absolutely perfect. As you say, the Daddy of meters.

[@AntonioClaudioMichael]

Great video Clive love the tester you made

[@zx8401ztv]

The 830b yellow and similar one is basically an ICL7106 chip from millions of years ago.

[@Christian_Banks]

The first time you showed that meter with the DC current clamp I looked one up and bought it. Amazing thing to have.

[@monadking2761]

Nice functional test for testing meters. It brought back memories. I was in the field of Metrology at a magor helicopter company before my broadcast career. Most analog meters are tested at full scale and digital too with standards. We used to test the electricians meters functionally like what you did and sticker it accordingly but, anything that touch the aircraft they had to be calibrated correctly. We would take reading at multiple points of the ranges with before data and if we did adjust, we had to have after data for traceability under NIST then under ISO 9000 and shorten the cycle time of the meter being used then find out if that meter was used on anything that was critical. It was a pain but interesting work. If you want an accuracy test use a Kelvin 4 wire bench ohmmeter. It uses the voltage drop method to display resistance on your lower resistances ranges with gold clips. I remember measuring conduction levels of connections of pins and measuring down to 10 to minus 9th place one time for repeatable tests because of a claim that the pins would ware after so many uses and the resistance would change. Just to prove Cramolin (ProGold) on connectors work better. It was weeks of testing and taking data.

[@peterburi2727]

I also have a Fluke 23.That has been my go to meter. A real workhorse and extremely rugged guy.

[@CrimeVid]

my Uni-T was delivered just before I found this video, you have given me some confidence in what is a very reasonably priced bit of kit !

[@FireAngelOfLondon]

This is a really helpful video, especially for anyone starting out who wants to know if a cheap meter will be adequate until they can afford a better one. The answer nowadays seems to be "Yes."