Where are you measuring your coil ohms when using a digital multimeter?

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Flt Simulation

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I am using a kayfun Lite ... Unfortunately, I don't have one of those devices that you can stick the base of the atomizer into in order to measure the ohms of your coil.

What I have to use is a digital multimeter. I guess it would be just as accurate as any other device to check the coils ohms when building, but I have a question about this:

Would the best way to check the resistance (ohms) of the newly made coil be to put the 2 leads of the multimeter on the 2 posts (screws) the coil is connected to?

Thanks
 

bce22

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folkphys

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I'm a bit obsessive about electricity so I always test first on the + and - screw posts/terminals inside the coil deck area. Then I flip the thing over and test on the 510 connection -- touching it in various places along the outer threading and inner screw head. I do both of these tests twice before and after wicking/filling....at least. And remember to subtract your meter's internal resistance as measured by touching your test leads' tips together.
 

^Top-Shelf^

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This might be a bit excessive but I check the wire after I've wrapped it before screwing on to make sure I don't need to add or subtract a wrap "easier to fix before it's all screwed down". If all is good I then screw it down, check again on the 2 screws after I've dry fired it a bit. Then after it's all wicked up and assembled I check from the bottom connector to get my overall resistance lol.
But yeah checking from the screws is fine
 

RWDY

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This might be a bit excessive but I check the wire after I've wrapped it before screwing on to make sure I don't need to add or subtract a wrap "easier to fix before it's all screwed down". If all is good I then screw it down, check again on the 2 screws after I've dry fired it a bit. Then after it's all wicked up and assembled I check from the bottom connector to get my overall resistance lol.
But yeah checking from the screws is fine
Nothing wrong with checking several times but i would check before dry firing. If you create a short while connecting the coil you could damage your battery or more importantly yourself.
 

rurwin

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You'll get a more accurate figure by checking the screws, because the probes will make good solid contact. Fiddling with the 510 connector, especially if you're holding the device in your hand while you do it, means you can't get much force pushing the probes onto the contact. And a screw thread provides a low contact area. On the other hand on the posts you are pressing both probes in the same direction, probably against a solid surface and, assuming they are cross-head screws, they don't slip around.

Unless you have a faulty device or a highly accurate meter, you won't see any difference between the two measurement points if you make good contact in both cases. Any difference will be negligible for all practical purposes; without doing the maths, I would expect it to be single-digit milli-ohms or smaller.
 

Legolas

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You'll get a more accurate figure by checking the screws, because the probes will make good solid contact. Fiddling with the 510 connector, especially if you're holding the device in your hand while you do it, means you can't get much force pushing the probes onto the contact. And a screw thread provides a low contact area. On the other hand on the posts you are pressing both probes in the same direction, probably against a solid surface and, assuming they are cross-head screws, they don't slip around.

Unless you have a faulty device or a highly accurate meter, you won't see any difference between the two measurement points if you make good contact in both cases. Any difference will be negligible for all practical purposes; without doing the maths, I would expect it to be single-digit milli-ohms or smaller.

The first build I did on mine I caught the silica in the chimney while I threaded it down. I had checked the build across the screws before I put the chimney on. The silica pull screwed up my coil by grounding it on the air hole and twisting it. I have a ohm checker and my mod does too so it was caught before I fired it but I think it's always best to check after it is assembled too. Just to be safe
 

bce22

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This might be a bit excessive but I check the wire after I've wrapped it before screwing on to make sure I don't need to add or subtract a wrap "easier to fix before it's all screwed down". If all is good I then screw it down, check again on the 2 screws after I've dry fired it a bit. Then after it's all wicked up and assembled I check from the bottom connector to get my overall resistance lol.
But yeah checking from the screws is fine

This is a great way of doing it, but I need different leads for my DMM to do this maybe some minigrabber leads.

I never thought about testing resistance at the 510 connector (duh!) and will do that too.

Thanks for the thread OP!
 

rurwin

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The first build I did on mine I caught the silica in the chimney while I threaded it down. I had checked the build across the screws before I put the chimney on. The silica pull screwed up my coil by grounding it on the air hole and twisting it. I have a ohm checker and my mod does too so it was caught before I fired it but I think it's always best to check after it is assembled too. Just to be safe
A good point. But then you don't need an accurate ohms measurement; you just need to be sure there's not a short.
 
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