Again and again we see the questions such like "how many wraps shall I do to get a 1 ohm?". Often the answer is "buy a multimeter" and then sometimes somebody answer "there is NO WAY to measure such low coil resistance by use of regular, cheap multimeter!". Is it true? Let's see...
I wrapped some microcoil on the MutationX atomizer and will measure its resistance by use of several multimeters. Starting from expensive, calibrated meter by Keithley. But first...
Measuring the resistance by use of multimeter first we have to know (and take into account) resistance of the measuring system.
(it means: resistance of probes/cables and internal resistance of meter)
We can do it in a very simple way: just performing a regular resistance measurement of shorted test probes:
As we can see the resistance of measuring system is 0.15 ohm. So it will be added to the each measured real resistance.
Now let's see what about the atomizer:
OK, we get 0.75 ohm. Knowing that 0.15 ohm is from meter we can calculate that the resistance of the coil is 0.6 ohm.
Fine, but what with budget meters? Let's take something around 30$...
Cables first:
Here we get 0.4 ohm in bonus. And the atomizer:
So after deducting we somehow get also 0.6 ohm.
But wait a second... I also have the cheapest multimeter from FastTech, for about 10$.
Cables:
Atomizer:
Lets calculate... What is the result? Really? 0.6 ohm again!
Och! I have also SXmini at hand:
And we also get 0.6 ohm (after rounding)!
So we shouldn't look for problems where there are none!
Today's electronics is such advanced that even multimeter for 10$ will be able to measure our atomizers with accuracy of 0.1 ohm - this is not rocket-science.
Of course there are limits - the main is resistance of measuring system: it is not proper to measure object whose resistance is lower than the resistance of the measuring system :-) So my deliberations are dedicated to resistance above 0.4 ohm (this is typical resistance of cheaper multimeters).
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