sx350 50w question

[tat32]

Hello
I've got a sx350 from seedy (very good vendor)
Just got a couple of questions When using the batt protection option with a single vtc5 at around 50w with .7 ohms coil. the batt power goes right down and the power pulses down to 10w and back. (it seems ok with double batts)
without the batt protection its seems ok with a single vtc5 is this normal.

If it is normal what would be best batt protection or full power.
Thank you

 

[Loco]

HI!

What fuses are you currently using?

 

[sparkyjuice]

Hello
I've got a sx350 from seedy (very good vendor)
Just got a couple of questions When using the batt protection option with a single vtc5 at around 50w with .7 ohms coil. the batt power goes right down and the power pulses down to 10w and back. (it seems ok with double batts)
without the batt protection its seems ok with a single vtc5 is this normal.

If it is normal what would be best batt protection or full power.
Thank you

The protection is reverse polarity protection this will consist of a diode of some description
The battery voltage will drop across this diode in normal use causing a loaded down single batt to give the fault described
Your choice if single batt I'd use no reverse protection myself


Sent from (who cares) using Planet of the Vapes

 

[tat32]

Hello
Thanks for your help
So is that normal when using the reverse protection? I think I'll use it without I've just got to be careful.

I'm not using any fuses I didn't know that sx350 needed them is that only if using the batt protection. Would you recommend using fuses without the protection diode if so what type & amps is the best and would fuses add extra load on the battery.
thanks

 

[Loco]

From my understanding, most people use parallel ptc fuses with adequate hold/trip current rating. Adds minimal resistance to the build but in fairness....for the space and hassle I find it hard to justify bothering. I'm not with my build, and i know others also haven't. The chip protects you to some extent, and using quality cells is a given.

As far as reverse polarity goes....using a sharpie to draw a + and - is more than adequate in my opinion.
Anyone with the ability to build a mod should have the ability to pop a well marked cell in the right way round

Feel free to correct me anyone, but from what I know/have read I consider this sound advice!!

 

[tat32]

Hello
I've been doing more experiments and it's working loads better now before the batt voltage drop was about 4.2v to 3.3v now it's about 4.2v to 3.8v when set to 50w.
the difference was it was soldered to the small tabs on the the bottom of the battery connector and now I've soldered it at the top next to the battery. I didn't think it would make that much difference the solder connections looked ok.

 

[Loco]

Glad you had some luck. Im guessing its down to what material the contact is made from + how far the connection was. I think in your other post you said you grabbed a battery holder off seedy?....I remember asking him what the contacts were made from, and he did advise soldering as close as you can. Least you have it sorted now!