Unmarked coils measured (Ohms) with new multimeter

[hesitantly]

I have a couple of Protank Mini 2 tanks. Today, I bought some wick, wire, and a multimeter (Radio Shack Pocket Digital - 2200820). l didn't think I'd ever do that, but...I did.

I have five coils I got online, which are supposed to be 1.8Ω, but are unmarked (not authentic Kanger), so I used my new multimeter to check the ohms. The readings on each are:
1 - 2.3 ~ 2.6
2 - 2.4 ~ 2.5
3 - 2.2 ~ 2.4
4 - 3.6 ~ 3.8
5 - 2.4 ~ 2.6
I couldn't get a stable reading for some reason, even though I thought my contact was stable, and some readings were outside the ranges I stated, but most were as written, and I did each one many times to be sure. Some videos I watched said to subtract the resistance of the multimeter's wires, but the user's guide for mine says:
"The resistance measurement compares the voltage developed across a known resistance (internal) to the voltage developed across an unknown resistance (external)."
So, does that mean that the readings I got should NOT be adjusted? (Even the reading I got from the two probes was unstable, varying from 0.0 to 5.something, so I wouldn't know what to subtract.) In any case, coil number 4 must be around 3 ohms, or more. I put it on my eGo-V, and cranked it up to 5v - lots of vapor.

So, to my questions -
Should I adjust the multimeter's reading for my coils?
Is quality control really that bad, that I'd get a 3Ω coil, instead of 1.8Ω?
Do you have any tips for me on how to get a more stable ohm reading?
Thanks.

 

[tobarger]

You do need to subtract the test lead resistance from the measured resistance with this meter
Try holding the test probes tightly together and note the displayed resistance
Do not hold the ends together with your fingers because this will put some finger resistance into the measurement
My meters all tend to be about .3 ohms

 

[hesitantly]

Thanks, tobarger. The first time I tried it, I got a pretty consistent .4 ohm reading. Then later when I did it again, it was pretty variable. I'll just use .3 unless I get a better reading.

 

[steel bender]

Any little movement, will cause the reading to change. You have to be as still as possible.

 

[hesitantly]

Being as still as I can be, I get from 0.0 to 0.4, changing every second or two. Mostly, .1 or .2.

 

[dripdaze]

Plating on the tips of the probes can cause some variability in the reading.

 

[hesitantly]

I skipped all those "hard" science classes in school, but I thought electricity was an exact science!

 

[TheAmazingDave]

I have the same meter. Nice little tool, but it does fluctuate just as you mentioned.

I'd recommend a Fluke, I have an old Fluke 16 (designed for HVAC service originally but works just as well) and the readings stay consistent at low resistance.

Also as mentioned, make sure you're factoring in the meter's internal resistance.

 

[dripdaze]

I have the same meter. Nice little tool, but it does fluctuate just as you mentioned.

I'd recommend a Fluke, I have an old Fluke 16 (designed for HVAC service originally but works just as well) and the readings stay consistent at low resistance.

Also as mentioned, make sure you're factoring in the meter's internal resistance.

Yeah. I don't understand buying cheap multimeters. I am slightly biased though after working on electronics for 30 yrs. Some meters are more useful as trash can ballast than anything else.

 

[TheAmazingDave]

Yeah. I don't understand buying cheap multimeters. I am slightly biased though after working on electronics for 30 yrs. Some meters are more useful as trash can ballast than anything else.

For basic stuff, the RadioShack is okay. I use it working on cars mostly, for voltage and continuity testing. The cont. tester actually latches unlike other cheapies, which makes it a-ok for the simple stuff.

But, yea, when working with a potential pipe bomb being held to my face, it's my Fluke or nothing.

 

[dripdaze]

For basic stuff, the RadioShack is okay. I use it working on cars mostly, for voltage and continuity testing. The cont. tester actually latches unlike other cheapies, which makes it a-ok for the simple stuff.

But, yea, when working with a potential pipe bomb being held to my face, it's my Fluke or nothing.

I have a Fluke 77 that I trust for my safety. Used Flukes can be found fairly cheap on that auction site.

 

[steel bender]

I have a cheap multimeter from walmart. I feel I can trust it because it has always read the same resistance/battery voltage as my svd. If you're not sure about something, it's best to have a backup for double checking.

 

[benamatic]

I have the same problem sometimes. I think it's the quality of the meter. Mine was only $20.

 

[edyle]

For measure the coil resistance of a coil that's already in a atomizer housing, I find just using my vamo is much easier than attempting to use a multimeter.
Screw the coilhead onto an evod or miniprotank base and screw the base onto the mod; measure resistance.

If I choose to measure resistance of something with the multimeter, I usually have an alligator jumper on the black lead anyway, so one side first clips onto somewhere, like the spire on the protank coil; that frees up one hand to hold the atomizer, then the other hand holds the red lead to touch the center pin.

 

[hesitantly]

Interesting, edyle. I was measuring with the coil taped to my desk pad. I'll try it in the contraption, somehow.

Edit: Having it on the base didn't make much difference.

 

[Frenchfry1942]

Some of the Mods are coming out with ohm readers. People that own stock in multi-meters should take note.

 

[hesitantly]

Some of the Mods are coming out with ohm readers. People that own stock in multi-meters should take note.

I got the multimeter for other uses, too, though. At my B&M, it was 20 bucks for an ohm measuring "box", and the multimeter was 30, at Radio Shack...and it sweeps the carpet, and does the dishes, too!