How To Measure Inductance By A Multi-meter?

[@johncoscia5258]

Very good , when does the internal resistance become a factor so to use formula C? Is it at a high frequency or do you need a sensitive ohm meter ? When to use mains power 50hz , is it the power rating of the coil? The resistor power rating if you use 100w globe ? Sorry to be a pain , amazing how often pie is used and accurate. Thanks .

[@diymade2175]

Good thought, Mate. To measure Inductance, it has been not an easy & simple task especially on high frequency. To be all things considered thoroughly, the best way is to try the experience a few times by using a normal multi meter and steps in the video then you'd figure yourself out and make sure to play safe! I'd use formula C for lower frequency range such as below a coupe of thousand Hz. In order to do electric project(s) properly, there are three steps (at least two steps) need to be done: (1) Design or draft a circuit, (2) experience or test, (3) Conclusion or may be, to do an improvement as well. Thanks for your interested & good luck! 👍👍

[@johncoscia5258]

@@diymade2175 Thanks for that .

[@premkumarbista6912]

On of the best videos on 'how to measure inductance by a multimetre,' I've ever seen on UA-cam ! Thanks a lot.

[@diymade2175]

You are welcome!

[@ahmadkhalidhotak9399]

was your results accurate ? please share

[@robert5861]

Finally found something insightful. Inductance with normal multimeter is not possible. Thank you !!!!!

[@diymade2175]

👍

[@warplanner8852]

I had no idea Donald Duck knew so much about electronics!

[@davey2k12]

😂😂😂😂 that's enough utube 😅

[@LawrenceKaneshiro]

Had no idea Donald Duck lived next to a busy highway. Watch the dogs ducky. JustSaying.

[@adnanah5608]

Well done, a very simple method to measure the inductance without using very cost instruments like oscilloscope, signal generator or an LCR meter.
Many thanks ... 🌹🌷🌹.

[@diymade2175]

Many thanks!

[@m.alig.5126]

agradeciendo el compartir de tu conocimiento, saludos!!

[@diymade2175]

👍

[@calculatingcapibara2914]

Thanks for the video. Some remarks follow:
1) In the second setup: One can not just substract the ohmic resistance of the coil (92 Ohm) from the measured impedance and expect to get the reactance. It leads to severe over-correction (>13%) here.
Instead:
ohmic resistance of the coil ^2
plus
inductance of the coil ^2
equals
observed-impedance ^2
...much like the equation of Pythagoras and that is no coincidence: current and voltage differ 90 degrees in an inductor. The currents in the inductor and its parasitic resistance are in phase, therefore their voltages are 90 degrees out of phase, which is reflected in the equation above.
Some rearranging as presented bij AdnanAH will show the value sought for. Ohmic error is in fact low here(

[@diymade2175]

Thank You for the interested. Good points and You are right in theory. Dealing with an inductance is a complex issue especially the one wants to get as accurate as possible however I recommended highly, experiences yourself in the way of this video has showed, such as try a few times to use the different resistors and get the varies voltage values then you'd get an acceptable or satisfied result(s). Thanks again for sharing your thought!

[@EdwardGreen-Hampton]

The formula seems inconsistent.
Results vary enormously depending on the value of R.
Why do the other methods involve costly instruments, then?

[@tedlarsen1132]

Clever insight and clear justifications. Just whish he would stop sniffing helium while doing the video! :)

[@diymade2175]

Good point! Actually they came from the sections of the video fast edited. Thanks for your interested!

[@duanestafford3293]

Thanks for this video tutorial. Accurate or not it pulled together much of what I had just been reading about inductors as I try to relearn things I once knew.

[@diymade2175]

Thanks & glad it helped!

[@vibudhajanindha5233]

very useful video. I thought that measuring the henry(inductance ) of the coil is very hard. I think these types of practical examples also cover huge theoretical parts very easily. Thank you

[@diymade2175]

Thanks a lot ! Yes, you are right and great point.

[@markhonea2461]

Thanks Mr. J.👍that is most excellent additional and corrective information.
I learned, many years ago, how to use algebraic equations to determine most pertinent values and actions of components in an electrical circuit, but something we did not address was inductive reactance, or microhenrys' although we were made aware the reactance was there and lenz's law did help me understand
Some counterintuitive characteristics of electricity. I still find myself doing the - I C E - and the -E L I - thing in my head, as I track through single but perhaps manipulated phase circuitry.ahaha! Those were pre-digital multimeter days, a different time. My instructor, Mr. Richard Deputy, whom I was EXTREMELY fortunate to study under, gave us all the little tricks and acronyms and he also said- "you will never use this in the field" . Mostly true that. Digital everything was just around the corner, but having the experience and knowledge that was passed on as it were, has been such a benefit especially when you have complicated circuitry with varied components throughout, well, it gave me the ability to at least have an idea of what to expect in many such instances, and recognize my mistaken calculations as well. Thanks again.
Edit youtube cut this out of original
- as I track through single but perhaps manipulated phase circuitry.ahaha 🤔 those were the pre digital multimeter days, a different time.
My instructor, Mr Richard Deputy was a brilliant and multi field expert and simply a font of useful knowledge and information and I was EXTREMELY FORTUNATE to have a couple years of his presence in my life.
I digress. Trying to fill in what youtube has mysteriously deleted from my original reply. This is very confusing , and a little out of context, but my previous 'edit' content should fit into the above diatribe and with your help all of this might make some sense!
Oh my gosh this is evolving into such a mess. I need to get the hell out here.
Have a good day everyone and thank you for your patience, and your input.

[@BaljeetSingh-nm8hu]

Very good explanation, very easy to understand and do. keep it up, God bless you.

[@diymade2175]

Thanks, you too!

[@toufikhantoufa3051]

Realy realy thank you ❤

[@diymade2175]

👍

[@randalldick3935]

Very good explanation. Thank you.

[@everythingyoumustknow5825]

A very useful video! Keep posting.

[@diymade2175]

Thank you, I will.

[@ahmadkhalidhotak9399]

ii was looking after this all over the internet finally found it but i am skeptical if this will measure it correctly or not. 5% of mistake is acceptable but not more than that. Has anyone tried this formula with acceptable results. Please share with us. Thank you DIY made very much for sharing this with us. Keep the good work up.

[@bparker86]

Great info mate cheers from North Atlantic USA

[@diymade2175]

Thanks for your interested! 👍

[@worldmusic8941]

North Atlantic USA?????????????? what you do there?

[@nimapeyman9765]

Exellent

[@diymade2175]

🙂👍

[@pdrobautista]

Thanks for sharing, I just was looking for a new electronic multimeter, now I am involve in car audio so I need to measure the inductance to design crossover, but no multimeter has the innductance measure

[@diymade2175]

Thanks for your Comment ! I'm glad it could help and good luck with your experience..

[@MarzLast]

LCR Meter are quite Cheap i brought one when i found out they exist and never looked back looks like a digital meter measures henrys resistance capacitors very usefull i use it to measure guitar pickups (inductors) as well as ohms and resistance very easy to use .

[@diymade2175]

Yes, you can do that way. Thanks! 👍

[@incxxxx]

You did not show how to obtain formula .

[@diymade2175]

Thank you for the interested Mate! The formula was created for the simplified calculation, it didn't meet logic equation strictly & theoretically but within a certain tolerance for the practical experiences and inductance calculation is always complicated especially on high frequency. You can refer to @adnanah comment(s) for more details. Enjoy watching & Thanks again. 👍👌💪

[@suniljandu3187]

Thank you for your good explanation 🙏🙏

[@diymade2175]

You are welcome !

[@raoulsen696]

thank you so much......one question is the 12v 20 watt globe a dc bulb or something else?

[@diymade2175]

Yes, correct. it was a DC 12 V & 21 W globe.

[@tombouie]

Impressive

[@diymade2175]

Cheers! 👍

[@ahmadkhalidhotak9399]

I made 2 inductors, 220uh and 1000uh. For 1000uh inductor used this method and i am getting 0.1 volts on a 6.7 ohm resistor and 0.1v across the inductor. After applying the formula the answer is very high, and when i connect the 220uh inductor i get 0 volts across the inductor and again 0.1 volts across the resistor which is again inaccuracy. Any help will be appreciated? 220volts AC applied with a 18 watts bulb, 6.7ohm resistor. Any comments ?

[@diymade2175]

Glad to know you've experienced and keep going a few more times so you'll be able to figure things out. From data you've supplied, I'd say: (1) Increasing the globe wattage, (2) Increasing the value of the resistor(s), (3) Using a low AC voltage such as 24V, 36V or 48V instead. The one of ways or ways of combination above can be used depending on your own condition. Have a fun and good luck! Thanks.

[@ahmadkhalidhotak9399]

@@diymade2175 if a formula is perfect, then the answer should come accurate for all situations, but i am not getting results. from your explanation now i should purchase another transformer to get 24v AC voltage, again a headache. and that future is also not known, will it work or not ? tuff times for us

[@calculatingcapibara2914]

Have a look at my post yesterday. It lists the problems you are seeing. Lower AC voltage or bulb wattage will not solve this, I expect.

[@calculatingcapibara2914]

The formula supplied by DiYmade earlier in the list of reactions:
" L = 0.00318 ( sq Z - sq r )^2 in Henry, where Z = VL / I"
can not be correct. This can easily be seen in an example:
Suppose we have a coil of 1H with 314,.. ohm parasitic resistance. Then the expression between parenthesis becomes zero. After multiplying by 0.00318 it is still zero, which is in contradiction with the starting data.
The correct formula was given by AdnanAH.

[@adnanah5608]

Dear Sir,
I reviewed your equation “C” for considerable inductor internal resistance and found that it’s not valid.
The correct equation is: L=0.00318*SQR((VL*R/VR)^2-r^2) in Henry.
So the inductance value of your experiment is (2.18H) not (1.91H).
Explanation:
Impedance of inductor is Z=VL*R/VR
As impedance of inductor is: Z=r+jXL
Then: XL=SQR(Z^2-r^2)
XL=SQR((VL*R/VR)^2-r^2)
L=0.00318* SQR((VL*R/VR)^2-r^2) ...”C” in Henry.
Many thanks.

[@diymade2175]

Thank you for your interested & comment. Formula C supplied in the video, it was not met strictly & theoretically but within a certain tolerant for the simple practical experience (The more accurate, the more complicated formula will be). The formula you have supplied, it does not appear right however the result of 2.18H is the more accurate one according to this particular formula: L = 0.00318 ( sq Z - sq r )^2 in Henry, where Z = VL / I. Thanks a lot again!

[@donpearson7222]

Your equation is correct. When measuring the voltage of the inductor, one needs to combine the internal resistance along with the inductance to get the corresponding impedance. Then one can calculate the resulting current by taking the voltage across the inductor and dividing by the impedance. I also get your numerical results.

[@calculatingcapibara2914]

@Don : to which of the equations are you referring, when stating it is correct?

[@donpearson7222]

@@calculatingcapibara2914 Adnam-AH. He properly took into account impedance for the inductor which included its internal resistance. The voltage reading VL is across that item.

[@calculatingcapibara2914]

You are referring to DIYmade as "He" here? DIYmade is on the right track when measuring 50 Hz coils at their own frequency. He is wrong in his substraction/correction for ohmic resistance, ignoring quantisation error and proposing a formula using the square of the difference of two squareroots. See my posts above explaining more. For fun, I did some tests myself. As expected, I had only very inaccurate results. Inductancies are complicated components, heavily dependent on frequency, current etc. There is no single easy method for measuring. Understanding the theory behind it can not be missed. Enjoy the hobby!

[@mikeadler434]

👍👍

[@SlowfingerJC]

I have been trying for hours to work out how R/2π*50 becomes 0.00318 R ???? Can somebody put me out of my misery and explain where the 0.00318 comes from? I thought I understood basic maths! Thanks in advance.

[@diymade2175]

Okay, I'm able to handle this: R / 2π*50 = R / (2 x 3.14 x 50) = R / 314 = R x 1 / 314 = R x 1 divided by 314 = 0.00318 R. So this is where the result of 0.00318 comes from (1 divided by 314). Thanks for your interested !

[@SlowfingerJC]

@@diymade2175 I did have an epiphany a few hours ago and realised it's the reciprocal of 2π f. Haven't worked on formula transformation at this level for 40 years. Thanks for the reply.

[@diymade2175]

👍

[@markhonea2461]

How could I be only the 313th Ike?
Humans are weird. Where I come from they would charge a fee to view such superior material......

[@diymade2175]

Good comment and you might have seen a lot. There are many places in the world, many things have been commercialized, at the same time, the same things offered free to public such as there are the public schools and also the private schools etc. This concept applied to the contents you watched on youtube. Thanks for the interested!

[@markhonea2461]

@DIY made perhaps I will bring the link for your presentation back to my home planet and you will pick up some subscribers!

[@diymade2175]

Great appreciated. The link is here: ua-cam.com/video/fuxHONPjxMc/v-deo.html
Thanks again! 👍

[@duanestafford3293]

One reason for missed likes is that the viewer found the video through a search. When not signed in they cannot leave a like or a comment. That was my situation just now. Because I really wanted to like this video and its comments I went to the extra trouble of signing in.

[@JJ-ro6kk]

Equation ( C) is wrong and not correct. Z= r + j 2pifL

[@diymade2175]

Thanks Mate & appreciated your input! 👍

[@mrbloo553]

π=3.14

[@diymade2175]

👍

[@aravindakshanm2705]

What is 3.18? How can get 3.18

[@diymade2175]

Thank you for the interested! You see: L = 0.00318 * R * Vl / Vr in Henry, it can be L = 0.00318 * R * Vl / Vr * 1000 / 1000 = 3.18 * R * Vl / Vr * 1 / 1000 in Henry. Then it also can be L = 3.18 * R * Vl / Vr in Milli Henry [L = 3.18 R (Vl / Vr) in mL for short in the video showed]. That's reason 3.18 showed. Thanks again.