Dual coils on provari doable?

Status
Not open for further replies.

HolmanGT

Vaping Master
ECF Veteran
Verified Member
Jul 2, 2013
3,545
5,329
79
St. George, UT USA
Had a dual coil fire last night but I destroyed one on accident tightening the finicky little trident post caps lol.
13/14 wraps of 30g kanthal each coil was 2.7-2.8 ohms.
Thanks for the help guys :)

Dominic,

First sorry to hear you damaged your rba but all is not necessarily lost.

Did you kill the termination post, can it be replaced?

Also if you use 32 or 34 Ga. wire you won't have to use so many turns. I'll bet 13/14 turns gets a little tight in such a small area.

If you need I can give you a link to purchase the wire... and it is really cheap.

By the way if you stripped the threads in the terminal post you may be able to re-thread it and use a slightly larger screw.

PS - you can probably find someone to do the re-threading for you. Most folks are not going to have those kind of tools just laying around the house.
 

HolmanGT

Vaping Master
ECF Veteran
Verified Member
Jul 2, 2013
3,545
5,329
79
St. George, UT USA
Got your pm before I saw your reply, I didn't strip anything, the screw driver slipped into the center of my coil and smooshed it lol.
Btw I'm wrapping micro coils so 13 wraps ends up small and fits pretty nicely


Sent from my iPhone using Tapatalk - now Free

Dominic,

You just made my day... I was so concerned that you stripped the terminal post.

If the 30 Ga. is working for you and the wick has breathing room between each coil wrap I would stick with it. The 32 & 34 are a little more fragile but manageable. But if the 30 Ga. works don't fix it.;)
 

Dominick0311

Super Member
ECF Veteran
Aug 27, 2013
314
454
32
Long beach
Dominic,

You just made my day... I was so concerned that you stripped the terminal post.

If the 30 Ga. is working for you and the wick has breathing room between each coil wrap I would stick with it. The 32 & 34 are a little more fragile but manageable. But if the 30 Ga. works don't fix it.;)

Lol nah man I wouldn't even be posting on here, I'd be in the bathroom at USO crying


Sent from my iPhone using Tapatalk - now Free
 

Dominick0311

Super Member
ECF Veteran
Aug 27, 2013
314
454
32
Long beach
Finally got a good one
13/14 wraps of 30g 1.3 ohms
eqanu4am.jpg

e7emehyv.jpg



Sent from my iPhone using Tapatalk - now Free
 

StarsAndBars

Ultra Member
ECF Veteran
Jul 13, 2010
1,094
739
42
Colorado
I don't know about dual coil RBAs. But I use dual coil cartos, and I prefer them. Remember, a dual coil carto that ohms at 2, is really two 4ohm coils. 5v runs each coil at mid 6 watts.

Negative. I see people posting all the time that running two coils halves the resistance. It doesn't. Running two coils doubles the amperage. Mathematically it works out about the same, but just know what the actual effects of dual coils are. When your multimeter reads 2 ohms on a dual coil, each coil is 2 ohms, which equals a total of 2 ohms.

For example: running two coils of 2 ohms each in parallel doesn't make it a one ohm circuit. It would still be a 2 ohm circuit, but draw twice the amperage.

So voltage, divided by 2 ohms, times 2.
 
Last edited:

tom_chang79

Senior Member
ECF Veteran
Aug 4, 2013
299
182
CA
Negative. I see people posting all the time that running two coils halves the resistance. It doesn't. Running two coils doubles the amperage. Mathematically it works out about the same, but just know what the actual effects of dual coils are. When your multimeter reads 2 ohms on a dual coil, each coil is 2 ohms, which equals a total of 2 ohms.

For example: running two coils of 2 ohms each in parallel doesn't make it a one ohm circuit. It would still be a 2 ohm circuit, but draw twice the amperage.

So voltage, divided by 2 ohms, times 2.

From the perspective of the battery or in Provari's case, output of the switcher, it's 1-Ohm with two 2-ohm coils in parallel. The fact that it draws twice the current tells you the total system resistance got halved. The coil's resistance, individually does not change. If the coils are identical, then the current would be split amongst each path...
 

StarsAndBars

Ultra Member
ECF Veteran
Jul 13, 2010
1,094
739
42
Colorado
From the perspective of the battery or in Provari's case, output of the switcher, it's 1-Ohm with two 2-ohm coils in parallel. The fact that it draws twice the current tells you the total system resistance got halved. The coil's resistance, individually does not change. If the coils are identical, then the current would be split amongst each path...

Sorry man but that is incorrect. The current isn't split, the current (amperage) is doubled (same current, but times two). This is why the Provari often won't fire dual coil. Have 2 coils douples the amp load. I don't have a pro vari but imagine it has an amp limitation, as do most mods (if not all) that aren't mechs.

More importantly nothing is halved. A pair of 2 ohm coils in parallel would equal 2 ohms, not 1. At 4 volts, that would be 4 amps.
 
Last edited:

Dominick0311

Super Member
ECF Veteran
Aug 27, 2013
314
454
32
Long beach
Sorry man but that is incorrect. The current isn't split, the current (amperage) is doubled (same current, but times two). This is why the Provari often won't fire dual coil. Have 2 coils douples the amp load. I don't have a pro vari but imagine it has an amp limitation, as do most mods (if not all) that aren't mechs.

More importantly nothing is halved. A pair of 2 ohm coils in parallel would equal 2 ohms, not 1. At 4 volts, that would be 4 amps.

Then tell me how my two 2.8 ohm coils meters out to 1.4 ohms?
It's not theory bro, it's fact. It seems everyone in here is on the same page but you.



Sent from my iPhone using Tapatalk - now Free
 

tom_chang79

Senior Member
ECF Veteran
Aug 4, 2013
299
182
CA
Sorry man but that is incorrect. The current isn't split, the current (amperage) is doubled (same current, but times two). This is why the Provari often won't fire dual coil. Have 2 coils douples the amp load. I don't have a pro vari but imagine it has an amp limitation, as do most mods (if not all) that aren't mechs.

More importantly nothing is halved. A pair of 2 ohm coils in parallel would equal 2 ohms, not 1. At 4 volts, that would be 4 amps.

V = I*R , where V is volts, I is current, R is resistance.

If I is doubled, R must be halved, to maintain same V

You are confusing individual path resistance with total (network) resistance...
 

HolmanGT

Vaping Master
ECF Veteran
Verified Member
Jul 2, 2013
3,545
5,329
79
St. George, UT USA
Sorry man but that is incorrect. The current isn't split, the current (amperage) is doubled (same current, but times two). This is why the Provari often won't fire dual coil. Have 2 coils douples the amp load. I don't have a pro vari but imagine it has an amp limitation, as do most mods (if not all) that aren't mechs.

More importantly nothing is halved. A pair of 2 ohm coils in parallel would equal 2 ohms, not 1. At 4 volts, that would be 4 amps.

StarsAndBars,

Not to prolong this debate if you would take a look here. It shows how to calculate parallel resistance and will actually calculate it for you. Your method of getting to the answer comes out right but the method it wrong.

This is door number 1:

Parallel Resistor Calculator R1 + R2 = equivalent resistor R resistance equiv total resistor finder made easy - sengpielaudio Sengpiel Berlin
 
Last edited:

tom_chang79

Senior Member
ECF Veteran
Aug 4, 2013
299
182
CA
I think we deviated from the original topic...

I think dual coil would totally be doable, but not at a two single-coil performance of what we usually subject our RDA or RBA.

I usually run my RBA at about 10-12W. If true dual coil RBA were to be experienced, we need at least 20-24W (25 to be conservative).

With Provari's 15W limit, it would mean max of 7.5W per coil, which is generally where I vape my clearo...

Doable? Yes. Enjoyable? Depends. Making a coil glow is not a sign it'll work good. The coil gets quenched in juice and the amount that it can overcome the quenching of the juice depends on more power.

The only vv/vw mod that can do 20W is the DNA 20...

Would be cool if Provari did a 20W-30W mod in the future... The draw back of creating such mod is, making sure your customer doesn't use lesser battery with higher internal R.

Two batteries with the same discharge rating can have different internal R (you see it everyday even when you have the same make/brand/capacity battery, varies from unit to unit) but they will definitely heat up at different rate...

The advantage of integrated battery (in e-cig world) over replaceable, like in the Provari, is that the connection of the battery to the PCB is stronger (less resistive), when pulling 4 to 6A from a 3.7V cell, push contact and spring contact will start to not be an attractive solution...
 

Dominick0311

Super Member
ECF Veteran
Aug 27, 2013
314
454
32
Long beach
I think we deviated from the original topic...

I think dual coil would totally be doable, but not at a two single-coil performance of what we usually subject our RDA or RBA.

I usually run my RBA at about 10-12W. If true dual coil RBA were to be experienced, we need at least 20-24W (25 to be conservative).

With Provari's 15W limit, it would mean max of 7.5W per coil, which is generally where I vape my clearo...

Doable? Yes. Enjoyable? Depends. Making a coil glow is not a sign it'll work good. The coil gets quenched in juice and the amount that it can overcome the quenching of the juice depends on more power.

The only vv/vw mod that can do 20W is the DNA 20...

Would be cool if Provari did a 20W-30W mod in the future... The draw back of creating such mod is, making sure your customer doesn't use lesser battery with higher internal R.

Two batteries with the same discharge rating can have different internal R (you see it everyday even when you have the same make/brand/capacity battery, varies from unit to unit) but they will definitely heat up at different rate...

The advantage of integrated battery (in e-cig world) over replaceable, like in the Provari, is that the connection of the battery to the PCB is stronger (less resistive), when pulling 4 to 6A from a 3.7V cell, push contact and spring contact will start to not be an attractive solution...

Scroll up on this same page and you'll see my dual coil build from last night.
Doable... yes
Enjoyable... YES

1.4 ohms @ 4.4 volts
Steaming away, flavor punch to the mouth

Sent from my iPhone using Tapatalk - now Free
 
Status
Not open for further replies.

Users who are viewing this thread