Please help me understand single coil vs dual coil drain on batteries!

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illitirit

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I have tried googling this for the past 40 minutes and while I have found some information, none of it seems to be fact. Just a bunch of opinions on random forums who negate each other post after post.

I want to know how the battery life of a single coil vs dual coil differs.


Here is what I understand and dont understand so far:

Given a single coil at 1 ohm vs a dual coil at 1 ohm (2x 2ohm coils), the ohms are the same. That would mean that the draw on the battery is theoretically the same correct? Or am I mistaken.

Then I read that no its not the same because in dual coil there is more thermal mass to heat up so you would be drawing more power from the batteries to light the coil.

So basically some people say that no there is no difference because the ohms are the same, then some people say that yes there is a difference because of the added thermal mass.

Could someone knowledgeable please chime in on the matter.[h=3][/h]
 

edyle

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I have tried googling this for the past 40 minutes and while I have found some information, none of it seems to be fact. Just a bunch of opinions on random forums who negate each other post after post.

I want to know how the battery life of a single coil vs dual coil differs.


Here is what I understand and dont understand so far:

Given a single coil at 1 ohm vs a dual coil at 1 ohm (2x 2ohm coils), the ohms are the same. That would mean that the draw on the battery is theoretically the same correct? Or am I mistaken.

Then I read that no its not the same because in dual coil there is more thermal mass to heat up so you would be drawing more power from the batteries to light the coil.

So basically some people say that no there is no difference because the ohms are the same, then some people say that yes there is a difference because of the added thermal mass.

Could someone knowledgeable please chime in on the matter.[h=3][/h]

1:
A 1 ohm coil whether single or dual would draw the same from the battery at the same voltage.
But the dual coil will need more voltage to vape properly.

2:
With the dual coil you will end up needing to draw more from the battery to get it hot enough.
 

illitirit

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1:
A 1 ohm coil whether single or dual would draw the same from the battery at the same voltage.
But the dual coil will need more voltage to vape properly.

2:
With the dual coil you will end up needing to draw more from the battery to get it hot enough.


Thanks for clearing that up for me. I appreciate it.

But when you say it requires more voltage on a dual coil, are you talking about on a variable voltage device?

I only use mech mods and I thought that whatever nominal voltage your battery supplies thats what your mod fires at.
I have 6x sony VTC5's in rotation and they are all rated at 3.7 v. So when I build a dual coil they are actually firing higher than 3.7v?

As far as drawing more power from the battery, are we talking double the amount of draw? I can go about 4 hours on a 0.8 ohm single coil with the vtc5, should I expect 2 hours on a 0.8 ohm dual coil?
 

anumber1

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They are the same as you have made your example.

However, properly wicked, in a RDA that has a decent amount of airflow, a 1ohm coil alone may perform better than two, 2 ohm coils.

Personally, I have tried two, 2.5 ohm coils (so I had an acceptable resistance to fire on my SID). I much preferred a single coil, 1.3 ohm build.

Now, I have the same RDA built with dual 1.5 ohm coils and it is a cloud making flavor machine.

But it is now on a mech mod.

I guess my point is: an ohm of load is an ohm of load to your battery. If you are trying to stay in a range of load for you device, you may be better off building a single lower ohm coil than two higher ohm coils.
Its a matter of coil temp and surface area. One lower ohm coil is going to get hotter, faster and may perform much better.

Sent from my XT907 using Tapatalk
 
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Dampmaskin

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So basically some people say that no there is no difference because the ohms are the same, then some people say that yes there is a difference because of the added thermal mass.

Could someone knowledgeable please chime in on the matter.

Both are right. For a X second draw, the battery drain is the same.

But when you double the thermal mass, you may want to do a 2X second draw, thus doubling the battery drain.
 

anumber1

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I only use mech mods and I thought that whatever nominal voltage your battery supplies thats what your mod fires at.
I have 6x sony VTC5's in rotation and they are all rated at 3.7 v. So when I build a dual coil they are actually firing higher than 3.7v?

You must use your batteries fully charged voltage as a base for calculating amperage. Fully charged IMR batteries are 4.2 volts. This makes a huge difference!

Get your head around ohms law. There are many ohms law calculators out there.

Here's one:
Ohm's Law Calculator
 

edyle

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Thanks for clearing that up for me. I appreciate it.

But when you say it requires more voltage on a dual coil, are you talking about on a variable voltage device?

I only use mech mods and I thought that whatever nominal voltage your battery supplies thats what your mod fires at.
I have 6x sony VTC5's in rotation and they are all rated at 3.7 v. So when I build a dual coil they are actually firing higher than 3.7v?

As far as drawing more power from the battery, are we talking double the amount of draw? I can go about 4 hours on a 0.8 ohm single coil with the vtc5, should I expect 2 hours on a 0.8 ohm dual coil?

A commercial dual coil on a commercial tank will need more voltage than the equivalent single coil in order to get up to the right temperature.

If you are using a mech, you can, and I recommend you should, use a dropin kick module: a simple example would be this:
1646300-4.jpg


Which for starters you can just set to 3.7 volts so you can get a regulated 3.7 volts even though battery will be dropping from 4.2 to 3.2 volts during the course of usage.
The one drawback is I think these actually output a pulsed 6 volt and not a flat dc output; I hear the evolv kick2 outputs a flat dc.

--
Back to the point:
If you are BUILDING your own coils on a plain mech then you have to carefully build your coil to a target ohms.
No the batteries do not fire a different voltage; the batteries are rated at nominal 3.7 volts; in reality they start at 4.2 volts fully charged and drop from there; it is not good to let them drop below 3.2 volts; (if you use the kick the kick will stop when the battery drops to 3.2).

How much power:
Power = volts x volts / ohms.

Half the ohms will draw double the power.

If you go 4 hours on a 0.8 ohm single coil, you should expect 4 hours on a 0.8 ohm dual coil on your mech.
But the dual coil will run cooler.
 

Ryedan

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i totally agree with you, but I only gave the 1 ohm coil(s) as an example to make it simple.

A single 1 ohm will far out perform a dual 1 ohm at least on my mech mod.

I would never build a dual coil at 1 ohm, more like 0.4-0.5.

I've tried a single 0.6 ohm coil in my Trident on a mech mod and it's great. With two 1.2 ohm coils, so the same 0.6 ohms total I get a slightly better vape for me. Yes the dual coils take longer to heat up, I can see that when I do a dry burn (might be able to change that by using thinner wire though). In real world use though it doesn't matter, I get good vapor off a three second draw either way. Now, I've never actually had both setups running at the same time in two Tridents to compare back and forth. I might notice some difference if I did that, but if it's so small that I had to do that to notice a difference it's irrelevant to me.

I find I get more vapor and flavor from the two bigger coils than from one. But that's in a Trident RDA using 27 gauge wire and my drilled out air holes. Also, my definition of a great vape might not be the same as yours.

Vape on :)
 
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