Voltage drop

[Don]

The load voltage would be the one to use. That reflects what is really going into the coils. My current measurements are undoubtedly low as the meter leads aren't short or heavy gauge. When I'm seriously testing current I use heavy solid copper leads just a few inches long. I'll charge up a cell and give it a go. Once I find my heavy test leads...

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Using an elderly Fluke meter, I get 5.56A at 3.28V firing on the Hammer mod into an 0.6 ohm atomiser. Or about 18 watts. That's about 0.92V drop on a heavy load.

[gords1001]

I always calculate at 4.2v - I'm aware I wont ever see that on a mech but it gives me a worst case scenario for if my cells will take it. Everything else is much of a muchness but cells being overloaded is definitely not something I want to risk.

As Don points out though, if you want accuracy, you should measure your voltage under load and calculate from there.

[Spasmod]

(19-03-2014 05:21 PM)Don Wrote:  Using an elderly Fluke meter, I get 5.56A at 3.28V firing on the Hammer mod into an 0.6 ohm atomiser. Or about 18 watts. That's about 0.92V drop on a heavy load.

What cell is that Don ? that's a hell of a drop for just 0.6 ohms

(19-03-2014 06:43 PM)gords1001 Wrote:  I always calculate at 4.2v

Exactly what I do also

[Don]

A freshly charged VTC4. I suspect the Hammer top cap/spring are playing up again. I've a Chi You clone top cap on order which JohnnyMac tells us will fit and cure the problem. Yep - it is. I'm seeing 0.3 ohms between the 520 pin and the battery tube.

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Yep. The copper I'd stuffed in had migrated. Replaced it with 2.5mm2 copper.

4.21V measured at the 510 no load.
Under load - 3.7V and 6.13A = 22.7W

The drop still seems a tad high. But is better. Flush fitting is no longer an option. I might just cut a bunch of lengths of solid copper to suit different atties. Permanent and cheap solution that still allows flexibility. Only problem is the projectile small pieces of copper

Different mod time.

Natural mod
Batt voltage 4.19
Measured at 510 - no load 4.19V
Voltage under load - measured from atomiser deck - 3.75V 
6.3A=23W

[Pulsar]

You would want to do it under load. Not 100% on this, because I am not an EE or nothing of the sort... but pretty positive

[apt323]

Figured that was the correct way of doing but just wanted to be sure. Thanks for the answers and numbers.

[Don]

Brass Origin clone
Cell voltage: 4.17V
Firing the 0.6 ohm Prometheus: 3.64V
Drop 0.53V but some fiddling will probably improve that

Brass M16 clone
Cell voltage: 4.14V
Firing the Prometheus:3.79V
Drop 0.35V

[Spasmod]

That M16 is very impressive, that's probably as good as you can expect from brass

[Don]

Poldiac clone
Cell voltage: 4.13V
Firing voltage:2.93V
Drop: 1.2V which I just don't believe.

[gords1001]

Thats not sounding right on the poldiac, the m16 is rumoured to be one of the hardest hitting clones available, cant help thinking one of the heavy duty springs from intloutdoor like I used in the private v2 would push it even further, I'm going to have to get one.