4-Wire Resistance Measurements - Workbench Wednesdays

Bench DMMs have an extra set of banana jacks called "sense." Known as a Kelvin or 4-wire measurement, these inputs accurately measure small resistances. Like, milliohms small. In this video, learn how to use a multimeter with 4-wire capability, prove 4-wire is more are accurate (in some cases), and a trick to get more accurate measurements with traditional 2-wire techniques: bit.ly/2GdaszE
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[@warplanner8852]

Thanks for eight minutes of straight, clear, and coherent explanation without ANY bullshit and never ONCE did you resort to cliche phrases like "Hello, KZbin". Grateful for the effort!

[@victormd1100]

you're welcome

[@cielitorobles6643]

I agree, very nice.@@victormd1100

[@bald_engineer]

@@cielitorobles6643 I don't understand why victormd1100 said "you're welcome." They had nothing to do with the video.

[@cielitorobles6643]

For me I agree with @warplanner 8852, I am thankful too. But I cannot see my comment anymore. Anyway, I like the video!@@bald_engineer

[@ybxnop7443]

Darn I've been learning this stuff for so long, watched so many videos but this is the only videos that made me understand the four wire measurement. Thank you!

[@joefrancisramos6812]

Very nice video! I used four wire sensing method in measuring ON resistance of the MOSFET. Thanks for bringing light to my old questions

[@rwd1973]

I got hold of two HP 3478a and had no idea what 4 wire resistance measuring was.....now I know. Thank you!

[@error079]

Uppercase M is for Mega. Lowercase m is for milli. en.wikipedia.org/wiki/Metric_prefix

[@gardenogauge]

Resistance thermometers often use the 4 wire method to overcome the effect of the lead length which can often be significant

[@UnpredictableViolet]

One of the most important applications for the 4W measurement is in tracing out shorts on a PC board. Not measuring resistors.

[@gammaraider]

Thanks for explaining! It's unlikely I'll ever need to use 4-wire measuring as I basically never use very small resistances, but it's good to know if it ever becomes relevant.

[@mex900]

if you design a PCB, it comes in handy with complex circuits where you can't find a short in the trace. That way the smaller the resistance and accuracy, the closer you're getting to the short.

[@gammaraider]

@@mex900 That's a good use, thanks for the tip

[@dzee9481]

Excellent Video in explaining the 4 wire Bench DMM. Too Bad hand held devices do not have that option. Looking at the $ wire measurement makes sense in measuring very small resistance. I was looking at build a milliohm meter for just that purpose but it would need to have leads that are no longer than a few inches. And it would only serve one purpose.

[@shaunhagan1610]

This is a great video.

[@phildodd9942]

Goodnes ! How sophisticated that things are these days ! It must take special construction techniques to build a circuit using milliohms resistors - a lump of solder being "in circuit" would wreak havoc ! Thank you for this very useful primer on the subject !

[@stanley3259]

Thank you this was really helpfull

[@JohnUsp]

Nice video, thank you.

[@TortureBot]

If you always make sure you're measuring resistance with the very tips of the leads, you probably don't have to worry that much about a difference do you? Also, when moving your clip leads from the first resistor to the other and back, do you think it's possible that you are relocating the clips onto the original resistor at a slightly higher position on the legs or lower position? Or possibly the clips are getting a tighter bite before or after you clip them on the second time? Would any of that make a difference?

[@kaybhee6]

any idea how to measure e field,, and magnetics in and around wire...to test wire quality

[@tonysfun]

Thanks for your videos! I like the way you explain it... I have question about your BTM: MP730028 5.5 digital bench-type digital multimeter. Can you make a review? I found it on Newark's website, but they have 2 versions - Why is one under $400 and the other over $500? What version are you using? The under $400 or the more expensive and why. I'm a subscriber now.

[@marcelkerouack6833]

one is 4.5 digits the other is 5.5 digits

[@aicisha]

This is the more expensive one. If you search on google "eevblog owon bench multimeter" you will find some discussions about it, opinions, review and some teardown photos uploaded by me.

[@tonysfun]

@@aicisha Thanks for your reply and I'll search for "eevblog owon bench multimeter" . Have great weekend.

[@jimmysyar889]

I used it when measuring the resistance of a piece of wire

[@1nakate]

Thank you sir

[@PankajYadav-hr8tp]

Hi There...nice video ,but i have a doubt that in such measurements ,why don't you go for bridge method of measurement

[@michaelmounts1269]

I typically just use the “Rel” key to zero out lead resistance on meter before measuring…much simpler and extremely accurate. I use this festure prinarily dealung with op amps

[@txkflier]

According to the specs on the MP730028 (200 Ohm range = 0.030% of reading + 0.005% of range), its uncertainty at 0.1 ohm is 10.03%. If you're checking a 10% resistor, you need a meter that's accurate to 2.5% in order to have a Test Accuracy Ratio (TAR) of 4:1. That meter is barely good enough to check a 1 ohm 5% resistor. At 1 ohm, its uncertainty is 1.03%..

[@mumblic]

4:35 milli is written as "m" not as small capital "M" (=mega) Please respect the basics principles of the metric systems. No matter how small you make that "M" is still is mega Volt / mega Ohm!!

[@JohnUsp]

Yes, I was confused, I thought was mega, no milli.

[@kuglepen64]

In you graphics you use a capital M to say mili. This is wrong. Capital M means mega. This is 101 stuff, and it is incredible that you would get something this elementary wrong.

[@andywest5773]

I'm pretty sure it's just a small caps font making it look that way.

[@bald_engineer]

Well, it is not a capital M. It is a small caps M. The font used does not have lowercase letters. It is why the “m” is significantly smaller than the Omega. Just like the “u” for Amp and Volt. Which is another small caps letter. (And yes I know I didn’t use a Mu there!) While the distinction was obvious to me, especially since I tend to write in small caps, I can see how someone not paying attention to the size of the letters could make the mistake. We will have to come up with something else.

[@TortureBot]

I knew what you meant, but with everything else being so accurate, it would probably be good to find a font that allows you to use a real lowercase m and the greek letter μ for micro as well.

[@kaybhee6]

M=mega,,,,, m=milli

[@DonnyHooterHoot]

Totally unused by 99% of people who have it! I guarantee it.

[@alejandrojorgedepaoli3708]

MOSTRALA por DENTRO. NO lo compren, es una porquería. A los 30 días falló la fuente (un asco de fuente: sin protecciones ni filtros) y pocos días más tarde el medidor de RESISTENCIA. Y la garantía? NO TIENE en ARGENTINA. OWON es lo más bajo en instrumental. NO tiren su dinero.

[@ahmedgaafar5369]

please change the horrible distortion guitar music.