More Accurate Ohm Meter

[jasonculp]

Is there a more accurate ohm meter available to us? My ELeaf ohm meter is not seeming to be accurate. The build that I just did shows .2ohms on Steam Engine. I wrapped one coil, mounted it in the atty and it showed .76 so I built another one just like it. I put it on the meter and it shows .38. I generally shoot for .5 but this was close enough. I wicked it up and adjusted my mod wet it and went to town. It is generating a lot of heat. Even the button is getting warm. It is kind of a crappy mod and the button has to be adjusted just right. I then pulled it off and grabbed the DVOM out of the drawer. It shows .8. I know this is wrong! My meter is not cheap, but it does not have a range for this low of ohms. I grabbed an old analog that I have out in my shed, and it barely moves the needle. All else has failed to give me any results so I put it on my MPV. It shows 0.0.

My other build shows .43 on my ELeaf, 1.2 on my DVOM and .4 on my MPV. I vape this all evening and it seems to work fine. It does get a little warm if I chain vape it.

I realize that

.43 is 32 watts at 3.7v

and

.38 is 36 watts at 3.7v

But does it make that much difference?

Edited September 9, 2014 by jasonculp

[Earthling789]

Your ELeaf is probably very accurate, the MVP, not so much.

I've compared coils on my Fluke DMM, Eleaf (just bought), no-name meter, and MVP, and get something different on all of them, but the MVP is usually the one farthest from the other three. The Fluke and 510 meters are usually pretty close, although I will admit I've not measured any coils below 0.8 yet.

Most meters are +/- 4 or 5%, so some variance is expected.

Watts are not that far off in your example, but Amps are what you should be more concerned about... lower resistance is higher amps, and you have to make sure your battery can handle those Amp loads.... 8.6A and 9.7A respectively. If you're battery is only a 10A battery... the lower resistance is really pushing the limits.

[jasonculp]

I'm using VTC4 Sonys.

I guess I am just too much of a nerd. I just read a good article of why my DVOM is not accurate at that range. I wish I would have bookmarked it. I had a few resistors laying around and checked them and the DVOM is pretty close. Apparently it is harder than you would expect to measure ohms that low. I may buy another 510 style. I have had my eye on the metal ones with the rechargeable batteries. I may build one based on the plans from here: http://electronics-diy.com/electronic_schematic.php?id=951 I just don't have the time.

But to be honest. I was just trying out my first dual, parallel, 28gauge, vertical build. I am terrible at the parallel builds. I think it was a too hot anyway. It just really concerned me that it was so much hotter than the dual, 26gauge, vertical builds I have been doing. It just doesn't seem like it would make that much difference.

[Compenstine]

I like my Fluke.

[jasonculp]

I agree. Fluke builds a good meter. (Probably the best) I donated my last good one to a previous job (I left pissed off and all of my tools went missing). I still have an old autorange at work that I got in college but it is terrible. The one I use now is an Extech It cost much more than my last Fluke, but I won it in a contest. At my previous job we were distributors for Extech instruments. It has great accuracy ratings, it just doesn't have a proper range to measure less than 1 ohm. The 200 ohm range is good, it just isn't as accurate as it should be that low and the display only allows for a 000.0 reading. I guess I am just being too picky.