Charging 2 x 6S packs

[millerman]

my power supply has a amp display and last night i was charging a 6s 5200 mah li-po at 5.2 and that had a draw on the power supply of 10.9 amps
as my supply is only rated upto 15 amps i could probably charge a 3s batt at the same time
i would say the answer to your question is no you need a 25amp 300+ watts

[Jamin_00]

Sorry to jump in here but I need to clear something up as I am looking at exactly what Gerd is in preperation for a 90 size elec.

Am I right in thinking that if I have a 13.8v 20A power supply, it is capable of putting out 276 Watts in total or 138 Watts per channel if using a 2 channel charger?

Therefore if I want to charge 2 x 6S 5000mAh packs together then that is 25.2V x 5A (1C charge) giving 126 Watts per channel or 252 Watts collectively????

So my power supply can handle it and I just need a charger with 2 Channels capable of putting out 126 Watts per channel?

Sorry if that doesn't make sense. All this elec stuff is new to me.

I was questioning all this not too long ago Tom and the post is somewhere.

Will dig it out.

Basically that power supply will suffice but it wont charge 2 big packs at 1c, you need more power baby yea

I went for a 540watt 11-18v 30a psu and it solid, dont not even get warm cahrging all my 13 packs on a hot saturday ready for the Sunday.

[Sieze2]

Tom your maths is correct. But please know that running power supplies near their theoretical max wattage can burn them out quickly. Commonly the max wattage stated is not the sustained max wattage, but simply the peak max wattage. The other day I overheated a 300w power supply simply running it at 220watts on a hot day. I would suggest to draw 20A you use a 30 amp supply, or to draw 30A you use a 40A supply. This will make them last alot longer IMHO.

Sorry to jump in here but I need to clear something up as I am looking at exactly what Gerd is in preperation for a 90 size elec.

Am I right in thinking that if I have a 13.8v 20A power supply, it is capable of putting out 276 Watts in total or 138 Watts per channel if using a 2 channel charger?

Therefore if I want to charge 2 x 6S 5000mAh packs together then that is 25.2V x 5A (1C charge) giving 126 Watts per channel or 252 Watts collectively????

So my power supply can handle it and I just need a charger with 2 Channels capable of putting out 126 Watts per channel?

Sorry if that doesn't make sense. All this elec stuff is new to me.

[Tom Burgess]

I was questioning all this not too long ago Tom and the post is somewhere.

Will dig it out.

Basically that power supply will suffice but it wont charge 2 big packs at 1c, you need more power baby yea

I went for a 540watt 11-18v 30a psu and it solid, dont not even get warm cahrging all my 13 packs on a hot saturday ready for the Sunday.

Thanks mate.

[Tom Burgess]

Tom your maths is correct. But please know that running power supplies near their theoretical max wattage can burn them out quickly. Commonly the max wattage stated is not the sustained max wattage, but simply the peak max wattage. The other day I overheated a 300w power supply simply running it at 220watts on a hot day. I would suggest to draw 20A you use a 30 amp supply, or to draw 30A you use a 40A supply. This will make them last alot longer IMHO.

Thanks mate, but if I am charging 2 5000mAh packs at 5A (1C) that is 10A??

[unwind-protect]

Thanks mate, but if I am charging 2 5000mAh packs at 5A (1C) that is 10A??

No, because they're 6S packs (around 25V) and your power supply is 12V; as the voltage is halved the current is doubled (for the same power) so you're looking at around 20A.

[Kozmyk]

2 x 5000mAh packs at 25.2V 5A (1C) is 10A Output - Correct

If the efficiency were 100% you'd only have a 24W (276W-252W) margin to play with.
That's 9% margin.
The efficiency of the charger is not going to be anything like 100% or 91% so you're going be trying to pull more out of the PSU than it can deliver.
You'd need to charge at a lower current to be safe. Maybe 20% or 30% lower than your 5000mah.
Even then, running the unit at Max all the time is bound to make it run hot.

On the PSU current rating issue.
A company wishing to exaggerate it's product's capabilities would quote it's Peak current capacity as it's maximum.
A reputable company would quote it's Continuous current capacity.
The question is "Is this manufacture reputable or not?"

I hope they're reputable cos I just ordered on of those RipMax ProPeak PSU's for myself.

[PsiLo]

Tom, as Neil says, because the psu is only 13.8v and the packs are double that you will effectively need double the amperage. So to charge 2 5000mah 6S packs you will need a minimum 20A PSU but realistically this will burn out very quick (ask me how I know!!). Go for a 30A supply if you can get one.

[Jamin_00]

Charging 2 x 6S packs

I'll send you a link Tom to one I got off eBay cheap.


I won't recommend the seller though as they the ones that screwed me on the second one.

[Kozmyk]

PsiLo - Could you tell us which make of 20A PSU you managed to fry?

Notsomuch to shame the makers as to forewarn any users who might be tempted to run theirs too close too the limit.

[PsiLo]

Koz, I fried the Pro Peak dual output one like this....
Fast Lad Performance

I currently have a fusion 200w but that is only 15A regulated output so just charge a single 6S on that at a time! Will be looking to get one of the ones like Ben posted a nice meaty 540W