How can you measure 0.1 ohm with a meter that can be off by "Basic accuracy is 0.15 Ohm or 0.2%, whichever is larger "?!?
sub ohming at .1
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How can you measure 0.1 ohm with a meter that can be off by "Basic accuracy is 0.15 Ohm or 0.2%, whichever is larger "?!?
Well considering the thread I was responding to said finding a meter that can read to .1 ohm is really expensive I went to google and found one that was cheep.
I agree that when you get that low the meter becomes useless.
I built a 0.09 ohm dual coil with 20 gauge wire at the weekend and it's the first time I ever felt my setup creaking under the load. After about six pulls (at 60watts), everything got hot; the batteries, the mod (IPV3 v1 with the 165 watt upgrade) and especially my MCV Forge v2. The atty was burny-hot, to be clear. The mod was only pulling around 2.4 volts but the very low resistance meant is was going beyond the 25 amp continuous limit of my Samsungs at around 27.
I normally run 22 guage kanthal in a 0.18 ohm dual coil (at 55 watts, uaually) and the difference is night and day. Even though 0.18 is still low, My Sigelei 100W Plus, IPV3 v1 and IPV3 Li all handle it without missing a beat.
I normally run 22 guage kanthal in a 0.18 ohm dual coil (at 55 watts, uaually) and the difference is night and day. Even though 0.18 is still low, My Sigelei 100W Plus, IPV3 v1 and IPV3 Li all handle it without missing a beat.
All of this talk about needing some kind of Fluke DMM to accurately read sub-ohm is ridiculous. There are many cheap 510 meters that can give sub-ohm readings to within a couple hundreths of an ohm.
Here is an example, this is a steam-engine calculation for .15 ohm using dual coils of 22 gauge kanthal with 2mm ID. Result is 6 wraps per coil.
And here is an actual build of dual coils of 22 guage kanthal with 2mm ID, 6 wraps each. This is measured on an inexpensive 510 ohm meter:
If you know what kind of resistance to expect and you are getting the results that you expect, a 510 meter accurate within a few hundreths is good enough. You know that the build is good. As far as putting that build on a safe mod or using a safe battery configuration, that is a different matter. But, as for the accuracy debate, no crazy expensive DMM is needed for reading sub-ohm.
Here is an example, this is a steam-engine calculation for .15 ohm using dual coils of 22 gauge kanthal with 2mm ID. Result is 6 wraps per coil.
And here is an actual build of dual coils of 22 guage kanthal with 2mm ID, 6 wraps each. This is measured on an inexpensive 510 ohm meter:
If you know what kind of resistance to expect and you are getting the results that you expect, a 510 meter accurate within a few hundreths is good enough. You know that the build is good. As far as putting that build on a safe mod or using a safe battery configuration, that is a different matter. But, as for the accuracy debate, no crazy expensive DMM is needed for reading sub-ohm.
With regulated mods the resistance doesn't factor into the amp draw though, only set wattage and battery charge level does. With 60w, and assuming about 90% efficiency of the chip, you were drawing around 16 amps on a full charge and around 21 amps if the battery was as low as 3.2v. And the ipv3 has two batteries, right? In which case you're splitting the amp load between the two. Everything probably got so hot due to the low gauge wire retaining the heat for so long.
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Which Samsungs have a 25A continuous discharge limit?
That is a Velocity. Its an awesome RDA. That one is authentic, so I can't vouch for the different clones, but the design of it is perfect. Easy deck. Huge adjustable airflow. A top cap that perfectly locks into place in front of the coils, everytime. I love it.
I don't think they make it in 30mm.
They don't come in 30mm YET!
That's one way to recognise a good topper - when they make a wide version.
No. If you have to ask you're not sure and it's a good thing to check it out before doing it
In this case the 0.1 ohm resistance had nothing to do with battery safety.
I can understand why everything was getting so hot!
27A out of those cells (assuming you have 25R's) is bordering on dangerous and will significantly shorten their life. You could try HB6's or VTC4's, to give you a bit more of a safety margin and longer battery life, when you're next shopping for batteries.
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You're quite right. To be honest, I only made that particular build because I fancied trying to build with 20 gauge wire. Turns out that - in my opinion - it was far too hot and didn't taste very nice so I was happy to get rid of it. I've been running dual coil builds with 22 gauge wire for nigh on a year now and they suit me. Nothing ventured nothing gained though, I guess.I can understand why everything was getting so hot!
27A out of those cells (assuming you have 25R's) is bordering on dangerous and will significantly shorten their life. You could try HB6's or VTC4's, to give you a bit more of a safety margin and longer battery life, when you're next shopping for batteries.
Well I don't think New York based AvidVaper is going to make a 30mm version. The design is very carefully thought out. Every measurement has a purpose. The chamber size is exactly what it is because it is a perfect balance of flavor without spit back and already leaves plenty of room for air circulation under the coils due to the raised-off the deck coil placement design. I think if this were exagerrated by another 8mm diameter, that you would lose some of the flavor.
China might do a 30mm clone, but I think that 30mm mods are becoming less popular recently, due to the widespread adpoption of dual 18650 box mods.
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