Batteries for Sigelei 150W TC and Uwell Crown Tank

[Nomzie]

Hi everyone,

I am new to vaping (3 weeks now) and I just love it . I started with iStick 40w and Nautilus Mini. As my second setup, I have just received my Sigelei 150W TC and Uwell Crown with Samsung 18650 25R batteries. Uwell crown comes with a 0.15 ohm NI200 coil. Using the ohm calculator, I noted that with this coil, I can not go beyond 60W/J with my batteries as the CDR for these batteries is 20A. As I have little idea about sub ohm vaping, I was wondering if I can get your kind guidance on the limits under which I should remain and the general safety measures with this setup. For instance, what could happen if I fire above 60W/J with this coil? And if these batteries are good enough for my mod and tank?

Please accept my apologies if I could not explain my question correctly

 

[IMFire3605]

Hi everyone,

I am new to vaping (3 weeks now) and I just love it . I started with iStick 40w and Nautilus Mini. As my second setup, I have just received my Sigelei 150W TC and Uwell Crown with Samsung 18650 25R batteries. Uwell crown comes with a 0.15 ohm NI200 coil. Using the ohm calculator, I noted that with this coil, I can not go beyond 60W/J with with my batteries as the CDR for these batteries is 20A. As I have little idea about sub ohm vaping, I was wondering if I can get your kind guidance on what are the limits under which I should remain and the general safety measures with this setup. For instance, what could happen if I fire above 60W/J with this coil? And if these batteries are good enough for my mod and tank?

Please accept my apologies if I could not explain my question correctly

Have to calculate your amp draw differently with a regulated mod compared to a mechanical. Max wattage/lowest battery charge state=amp draw. In the case of the Sig150TC being in a series battery config (150watts/6.4volts=23.4375amps (lowest battery state is 3.2 on a single battery X2 is 6.4 here), and technically with those Samsung 25R batteries max wattage would be 128watts, the 150TC maxes out in TC mode I believe at 100Joules (watts). In regular power mode to go the full 150watts you will want either Sony VTC3 (1600mah true 30amp), Sony VTC4 (2100mah 20amp but capable of 30amps), or the LG HB6 (1500mah true 30amp)

 

[dc99]

I run mine on LG HD2's which are 25a but can do 30.

 

[Nomzie]

Thank you very much for the elaborate guidance. Does this mean that with respect to battery amperes in regulated mod, coil resistance is irrelevant? If I remain under 128 W or 100 Joules, am I good to go? And finally, why we calculate amp draw differently with regulated mod?

 

[IMFire3605]

Regulated mods most times have a boost circuit, set a certain voltage or wattage, if the battery charge isn't enough to fire at a certain setting, the boost circuit pulls amps from the battery to convert them to volts, fresh charge it isn't needed, but when down below 3.7volts or so, the boost circuit gets used more, so using the highest wattage divided by the lowest battery output to find amps is the best solution, it is still Ohm's Law, just a different formula. In a mech or unregulated we take the Resistance and highest charge state to determine amp draw as that will be the highest amp draw required from these types of devices. Resistance still plays into a factor with a regulated mod yes, thus they are programmed a range they will accept, 0.1ohm up to about 3ohms in non TC wattage mode is the range the Sig150TC accepts, it uses this to adjust its voltage output required using an Ohm's Law formula for wattage, if a coil is unsafe for it to fire, it won't fire, so resistance in a safety aspect is controlled by the board programming inside, unlike with a mech the resistance is your only throttle and the type of battery your only safety.

 

[Nomzie]

Many thanks for such valuable input.

 

[dcfluegel]

howdy - and welcome!

maybe i am missing something, but given that that is specifically a TC coil, how much wattage do you really need there - shouldn't you be setting a temp as primary parameter? i run a .25ohm kanthal coil in my uwell on the sig 150tc box but really only run it up to around 70 watts or so (using samsung 25r's) and it's a great vape for me...

 

[OldSalt]

No, resistance is not irrelevant. Current = voltage / resistance, and power = voltage X current. Keeping it simple; a regulated MOD (for power) adjusts the voltage so that the power is maintained at a set point.

Using the two equations above, power = voltage X voltage / resistance; therefore voltage = square root (power X resistance)

so, for a 0.5Ω coil, fired at 75W the voltage would be about 6.1 volts, and for a 1.0Ω coil fired at the same 75W would be about 8.6 volts. A voltage modification circuit in the MOD will produce this from a 6.4V battery.

The approximate current at 75W through a 0.5Ω coil would be 12.3 amps, and for the 1.0Ω coil would be 8.7 amps. Remember this is at the coil - not the battery.

Before I discuss the battery, I need to touch on the voltage modification circuit in the MOD. It's not 100% efficient, so when you fire the MOD not all of the power goes to the coil, some is dissipated as heat by the electronics. Most MODs have an efficiency above 90%, but some are below that. To be safe, I choose to use an efficiency of 80%. This means that to deliver 75 watts to the coil the battery has to deliver 75/0.8W or 93.75 watts. Your almost discharged 6.4V battery would need to pump out almost 15 amps, regardless of the coil's resistance.

With this background, let's look at your 0.15Ω coil, driven by two Samsung 18650 25R batteries in series. At worst case, almost discharged they deliver 6.4 volts and the CDR is 20 amps, so the maximum power from the battery is 128W. Allowing for 80% MOD efficiency, maximum power at the coil should be about 100W. Your 0.15Ω coil will draw 26.8 amps at 3.87 volts for 100W.

The specifications of the Sigelei 150W TC don't state whether or not a boost circuit is used to enable you to vape at this power level with your batteries. I'd contact their customer service department and ask.

 

[Nomzie]

No, resistance is not irrelevant. Current = voltage / resistance, and power = voltage X current. Keeping it simple; a regulated MOD (for power) adjusts the voltage so that the power is maintained at a set point.

Using the two equations above, power = voltage X voltage / resistance; therefore voltage = square root (power X resistance)

so, for a 0.5Ω coil, fired at 75W the voltage would be about 6.1 volts, and for a 1.0Ω coil fired at the same 75W would be about 8.6 volts. A voltage modification circuit in the MOD will produce this from a 6.4V battery.

The approximate current at 75W through a 0.5Ω coil would be 12.3 amps, and for the 1.0Ω coil would be 8.7 amps. Remember this is at the coil - not the battery.

Before I discuss the battery, I need to touch on the voltage modification circuit in the MOD. It's not 100% efficient, so when you fire the MOD not all of the power goes to the coil, some is dissipated as heat by the electronics. Most MODs have an efficiency above 90%, but some are below that. To be safe, I choose to use an efficiency of 80%. This means that to deliver 75 watts to the coil the battery has to deliver 75/0.8W or 93.75 watts. Your almost discharged 6.4V battery would need to pump out almost 15 amps, regardless of the coil's resistance.

With this background, let's look at your 0.15Ω coil, driven by two Samsung 18650 25R batteries in series. At worst case, almost discharged they deliver 6.4 volts and the CDR is 20 amps, so the maximum power from the battery is 128W. Allowing for 80% MOD efficiency, maximum power at the coil should be about 100W. Your 0.15Ω coil will draw 26.8 amps at 3.87 volts for 100W.

The specifications of the Sigelei 150W TC don't state whether or not a boost circuit is used to enable you to vape at this power level with your batteries. I'd contact their customer service department and ask.

I am trying to make sense of the mathematics here and I must say it is great learning for me. However, I am not sure if I can explain this discussion to Sigelei customer services . For now, the Uwell Crown tank has come with a 0.5 ohm dual SS coil, 1.2 ohm single SS, and 0.15 ohm dual Ni200 coils. What wattage/joules range is safe with these coils when using Samsung 18650 25R batteries on Sigelei 150W TC MOD?

 

[IMFire3605]

Giving wiggle room on the battery limits, 100watts or 100joules or under you will be just fine. That gives 28 to 30 watts extra overhead for a mishap and such.

 

[edyle]

Thank you very much for the elaborate guidance. Does this mean that with respect to battery amperes in regulated mod, coil resistance is irrelevant? If I remain under 128 W or 100 Joules, am I good to go? And finally, why we calculate amp draw differently with regulated mod?

With a regulated mod, what matters is whether the battery can supply the wattage demanded by the mod.

The coil resistance is only relevant to the mod, not the battery.