Measuring Voltage and Resistance

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stuvix

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Hey guys,
So I just got myself a multimeter to play around with. I know how to use it (the basics anyways) and I was able to get a reading of 3.94 V for my LT's battery which is 2200 mAh (18650 I think?). I'm now trying to measure the actual voltage coming out of the device but I don't know where to put the leads. I also want to see what the resistance is of my various atty's, but again, I just don't know where to put those leads.

Any help would be greatly appreciated! :vapor:
 

invididual

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EDIT: ok this was challenging, but i think i got it, i couldnt fire it, but this should give you a general idea (i hope)

touch the red (positive) to the center post and the black (negative to the outer ring while you're pressing the button to fire it
Photo_00004.jpg

as for the resistance, red in the bottom hole and touch the black to the side of the post
Photo_00005.jpg
 
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stuvix

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Perfect! Thanks! I had to get a friend to help fire the button, I couldn't do three things at once haha.

I switched my multimeter to the 200 ohm range and on one regular atty I got a reading of 3.6 ohm; on the one that came with my LT, I got 4.8 ohm (which seems high to me) and then a LR one I have is at 2.4. I know it's somewhere here on the forum but what would constitute a "high resistance" atty?
 

MASTER0FDAMPF

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You need to tough the two leads together to measure the resistance of the leads. Then subtract that from the reading.

e.g. If the touched ends (red and black bits) read .8 and the atty reads at 2.8, then the atty is really 2.0


I would set ohms for 20 though for better accuracy. NEVER run a continuity (closed circuit) test or take a resistance (ohm) reading off a battery with a meter not designed to do so. This could damage the battery.
Be careful not to hit both parts of the atty connector when firing it, this would cause a short. Supposed to be protected but....better safe than sorry.
 

stuvix

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You need to tough the two leads together to measure the resistance of the leads. Then subtract that from the reading.

e.g. If the touched ends (red and black bits) read .8 and the atty reads at 2.8, then the atty is really 2.0


I would set ohms for 20 though for better accuracy. NEVER run a continuity (closed circuit) test or take a resistance (ohm) reading off a battery with a meter not designed to do so. This could damage the battery.
Be careful not to hit both parts of the atty connector when firing it, this would cause a short. Supposed to be protected but....better safe than sorry.

Ahh, that makes sense. My leads were at 0.8 ohm, so that brings those readings down quite a bit. 200 ohms is the lowest setting on the multimeter I bought so I'm stuck with that for now. Thanks for the tips, very helpful. I'd be most upset if I shorted my batteries!
 

invididual

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You need to tough the two leads together to measure the resistance of the leads. Then subtract that from the reading.

e.g. If the touched ends (red and black bits) read .8 and the atty reads at 2.8, then the atty is really 2.0

very good info, my leads are reading .7-.8 resistance as well and thats just about how off the carts resistance was reading, good info to know... thanks Master! :toast:
 

MASTER0FDAMPF

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anytime...sorry about the 20 ohm thing...I have a pro meter with nice leads (fluke that is a few years old) so I forget that alot of you only use them for vaping. Happy to help.

The average for 3 ft leads is .8ohm - in case you were wondering how I guessed so close. The high purity leads I have are 5 ft and are .22 ohms. The meter will take it down to the 1/1000ths for accuracy. My dad helped me pick it out a few years back when I started learning electronics repair for fun (yep, I am a nerd/geek, but I am ok with that).
I was shocked at the accuracy of my LT as well, I love it for the price!
very good info, my leads are reading .7-.8 resistance as well and thats just about how off the carts resistance was reading, good info to know... thanks Master! :toast:
 

stuvix

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anytime...sorry about the 20 ohm thing...I have a pro meter with nice leads (fluke that is a few years old) so I forget that alot of you only use them for vaping. Happy to help.

The average for 3 ft leads is .8ohm - in case you were wondering how I guessed so close. The high purity leads I have are 5 ft and are .22 ohms. The meter will take it down to the 1/1000ths for accuracy. My dad helped me pick it out a few years back when I started learning electronics repair for fun (yep, I am a nerd/geek, but I am ok with that).
I was shocked at the accuracy of my LT as well, I love it for the price!

I'm also quite the nerd (science geek for sure). I took physics in my undergrad and I'm slowly remembering my electricity lectures. It would be great to have some nicer equipment for this, I just never had a use for any electrical gear until I started e-cigs. I was looking at a Darwin, but at a ~1/3 the price, I couldn't say no!
 

MASTER0FDAMPF

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an old carto with the outside tube cut down to about 1/4 inch will expose the positive lead to the coil. Clip off the coil and now you can test easier. Just clip the negative lead to the body of the cartomizer and your positive can touch off the exposed wire that powered the coil.

dead carto's are good for a alot when it comes to DIY testing for gear. basically they are just prewired atty connectors. If you cut out 3/4ths of the side of a carto, like a window leaving the top and bottom whole. Yank out everything except the positive (center) pin wire that runs to the coil and clip it at the coil. you can use a cheap pre-wired batt connector from madvapes to make an "underload" adapter by running the wires in from the top of the windowed carto and pressing it into the carto top. connect the red wire from the batt connector to the coil wire that runs up from the center pin of the carto. Connect the black to the carto body or the other coil wire that is soldered to the carto body. use simple insulated aligator clips crimped to the wires (or soldered) and voila! clip to your leads and fire away with any atty that you want.
 
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stuvix

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I'm definitely going to try this. Thanks again!

an old carto with the outside tube cut down to about 1/4 inch will expose the positive lead to the coil. Clip off the coil and now you can test easier. Just clip the negative lead to the body of the cartomizer and your positive can touch off the exposed wire that powered the coil.

dead carto's are good for a alot when it comes to DIY testing for gear. basically they are just prewired atty connectors. If you cut out 3/4ths of the side of a carto, like a window leaving the top and bottom whole. Yank out everything except the positive (center) pin wire that runs to the coil and clip it at the coil. you can use a cheap pre-wired batt connector from madvapes to make an "underload" adapter by running the wires in from the top of the windowed carto and pressing it into the carto top. connect the red wire from the batt connector to the coil wire that runs up from the center pin of the carto. Connect the black to the carto body or the other coil wire that is soldered to the carto body. use simple insulated aligator clips crimped to the wires (or soldered) and voila! clip to your leads and fire away with any atty that you want.
 
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