EEVblog #26 - Multimeter Tutorial - Counts, Accuracy, Resolution & Calibration

[jpmcbride]

First I want to say great video - good information. I want to slightly correct one of your terms though. The term "traceablity" when it comes to calibration does not refer to the historical record of the item as you said. It actually means there is a traceable path through the measurement standards used to calibrat ethe item. (transfer standards, back to primary standards, etc...)

[EEVblog]

@jpmcbride The term is used in many contexts, and often refers to the entire traceable path, including the history of the instrument itself.

[NMOEG]

when we talk about Calibration we always mention the fluke 87 V which makes me feel very bad and unsafe coz every time i need 2 measure something i feel it is drifting away and i dont have another multimeter.is the Fluke 87 V needs to be calibrated once in a while even if i dont use it that much ? im thinking to buy another one Fluke 179 ,never heard any said any about clibrating this meter ,does it need to be calibrated once in a while just like the Fluke 87 V ?

[eurokid83]

@NMOEG Why are you so worried about calibration? I have a few older 87 meters and they are just as accurate as my 87V and they have never been calibrated.

[ion010101]

I don't understand. I thought resolution was how sharp a picture was. I've never heard it used in this context. Does it mean how high up you can count in a range? Thanks.

[EEVblog]

@ion010101 the word resolution has many meanings in many different industries. How high is the "count" or full scale. The resolution is the least significant digit.

[XINXAN7515]

bloody good video mate

[sirsideways]

Thanks for the bit at 6 mins in, it was very helpful!

[0000mastermind]

hey dave......GOOD JOB!!!! greating from Trinidad & tobago....i'v looked at alot of your vids and learnt alot....i have never owned a multimeter before, but i want to get myself one for automotive and home use. I happen to like the yokogawa TY530 and TY720, I know both are not the automotive type but can you do a review on them?? My girlfriend likes the "sex on a stick" she said we shoud try it lmao.....

[ValiRossi]

Is that an old simpson 260 back there on the shelf.

[reddog694uk]

Hi Dave, How about a review on the fluke 77, Lots of these available cheaply now as ex-military contract and should be great quality. You're the man when it comes to showing us beginners what's what. Love the vids and appreciate the help!!

Mark

reddog694

[tabarin]

Great introduction thanks

[HobieTyourtube]

Dearest Dave!-we ALL don't live in a "constant "enviroment?

Temperatures-change?

You are "anal "about .0001 of a change?

When in "truth "------------.01 of a change-is "Good? "

Haha--------------it is ten Volts?------------not---------­-----10.0000001 volts but----.99999 volts?

Basic Electronics-means THAT?----------Oh!!-------ten Volts has been measured across a-resistor?

You have "given"cheap multimeters a-BAD NAME?

In my day-I had to align my-eyes across a -mirror image!-analogue meters

[aao331]

This is the best and most informative EE blog ever ! Thanks you very much.

[shodanxx]

bullshit me that is)

and I know this is probably beginner stuff and a really great thing about your blog is that you go in-depth about stuff and don't assume you're talking to noobs and you probably think this is a bit boring to talk about ... but I think it'd be really great

in fact I would love to help you do that !

wow that 500 character limit is really a pain in the ass !!!

[shodanxx]

(and I think this is true for other tools "everyone knows" how to operate like the function generator/counter even adjustable power supply and the big one, the oscilloscope, I have 2 of them analog ones, and I plan to get a pair of those sweet Rigol ones but I don't know what half the buttons do on them and I tried asking electronics students and the local electronics shop guy and they just stare blankly and say I'm not really sure what that button does, when they don't

[shodanxx]

you say things like "people get it wrong all the time" and "everyone knows" but I think a lot of people DON'T know, and you know that, and that's why I think such a post would be very valuable to the community as a end-all go to ressource for all things multimeter, somewhere to send all the noobs and the not so noob to learn something or consolidate training, that would be wonderful !

[shodanxx]

that was real interesting !

with that and that other post about voltage burden, maybe you could have a post where you go through all the other critical characteristics of DMMs ?

I have a fluke 87III and there's so much I don't know about it

like how to use that REL delta button, or how to test transistors with it

it be great to have a video that is a single reference for all thing about, and that you can do with, a multimeter

[Ryantron9000]

Thanks! I never understood what this meant until know.

[Films4You]

Excellent Demo :)

[gmcjetpilot]

What is the most accurate DMM on the market for something under say $300 or $400?

What is the best value in Fluke (used or new) .... I know the Fluke 87 V is great, but is it much better than a 87III or 77 or 15B or 17B for basic Volt\/Ohm/Current. I am not too worried about Temp readings but capacitance would be nice. Still I can use a separate meter for LC.

[BizOppTracker]

do i really need a 'megger' or a 'fluke' instrument to test domestic installaitons? They cost about £600 a go and surely the company cant warrant that amount of money when you can buy mutlimeters for much less??

[theamberco]

hahahahahah dueling banjos hahahhaha

[theamberco]

hahahahahahaha Dave that was a good response to that asshole I could not do it better and I am really good at that too ......dueling banjos hahhahahahahahaa.

[TelevisionMagazine]

Great information. Stuff we just don't think about day to day using these!

[getbusy21]

Thanks for the info. Fluke 16 rocks!

[gpajmd]

any one knows how to reverse digital speed o meter of car?

[nmbookie]

Good descriptions, I like the enthusiasm and obvious wish of the presenter to be helpful.

.

[Phyle9]

good info! thx

[bag2drag311]

great video, thanks

[krankiev]

you don't have to just insult him based on how he talks man...

[1972FordF150]

Well, shit at first i thought he was but now.... not so much. Cus i was laughing so hard..

[EEVblog]

Ok, point us to yourself on video and we can all have fun judging YOU. Based on your username and the way you speak, my money would be on you being a pick-up truck driving, tobacco chewing, god and country music loving, undereducated, backwater redneck yank. But that's just a guess...

And why am I hearing dueling banjos?...

Go on, post a youtube video response, I dare you.

[1972FordF150]

BUAAHAHAHHAAH say you're funny, AND not a fag !!!!!!, And I'm 13 years old dude. I was just kidding and I'm sorry about that. Okay ? And what is wrong with my user name ? Dude it was just made up for god sakes.

[1972FordF150]

LOL say that's funny !!! and I have no idea how to even play a banjo. And I HATE COUNTRY MUSIC !!!! ROCK AND ROOL FTW !!!!!!

[rookman31]

@EEVblog ....Hey great video. Your enthusiasm makes you a great teacher and I look forward to more videos to come. Having said that just ignore these other little shits who can only sit behind a keyboard and talk shit but dont have the balls to put up there own video.

[jfleming006]

@EEVblog HAHAHA!!! You are right - go to his channel!!!

[dufondutrou]

a danst or what ever that is or a faget!

[kchida1980]

nice video as usual. it's weird that the resolution limits are nice even numbers in decimal. you would think that the resolution limit would be a binary number, which, in decimal, would seem like a strange number (i.e. 1024 in decimal seems weird to someone that doesn't understand binary numbers).

[mtttee2]

If calibration only checks on the history of the multimeter's accuracy, what happens if one day my multimeter's accuracy drifted away. Will they readjust it back to specifications?

[EEVblog]

Yes, that's a normal part of the process too. It doesn't even have to be outside the specs for that to happen, just enough to doubt that it will remain within specification for the next interval. In this case they usually give you the before and after adjustment figures. And the serious user will drop the cal interval until confidence is restored in that meter.

You can also specifically ask for adjustment every time regardless.

[mtttee2]

Know I see the point. If the meter has a good precision then no point to readjust it. When the precision is bad then they will readjust it. All of this readjustment depends on the user's requirement. Am I right?

[japroach]

I was surprised as well that calibration does not mean adjustment the majority of the time. but its completely logical.

Good stuff as usual.

[ntjbjhq]

Good info, thanks again for another great video!

[chromebeats]

the 3999 one doesn't make sense to me.

The most significant number , i can see it being 1 or 3 but 2 would use the bottom left of the 7segment, so why not just give it an entire segment?

You only save the top right segment anyway.

[EEVblog]

It's not about saving display segments, it's the count range of the ADC. Higher count ranges need a higher resolution ADC, which is more expensive and trickier to implement with good accuracy.

[chromebeats]

That does indeed make more sense