Cellpro question

[whaleboy]

Can I charge using 2 cellpro's on a single 7amp power supply? Will be charging 3s packs.

Thanks

-David

[kamtsa]

Can I charge using 2 cellpro's on a single 7amp power supply? Will be charging 3s packs.

Thanks

-David

Grounding wise, you are OK since they are independent packs and not halves of a 6S packs.

As for current rating, this is a little bit tight but will probably work.

Kam

[th3tick]

The way I figure it is this: you're going to be charging a 3S pack at 11.1-12.6V. That is pretty close to the voltage the PS provides, so amps you select to send to the pack should match fairly closely the amps the charger will pull from the PS.

So, if you have a 7A PS, keep the selected charge amperage under that, and give it some margin for losses in the charger.

Deciding the amperage of charge is then dependent on the size of the packs. If you're charging 2200mAh packs, then a 1C charge would be 2.2A, so 4.4A should be fine. If you choose to charge them at 2C, you'd might be at a total of 8.8A for part of the charge, so that's not good.

If you're charging 5000mAh 3S packs (does anyone make that size?), then 1C charging them both is too much, at 10A.

John

[whaleboy]

Can you have a PS with too many amps? I guess as long as its 12v, the charger will just pull what it needs? I'll be running two 3s packs in series (to make a 6s, 2500mAh), but only have a single charger at the moment. I was considering a 2nd cellpro, or a cellpro 10, but I don't want a bulky PS... However, if I get a second cellpro4, I'd need yet another charger if I decide to move to dedicated 5 or 6s packs... Argh...

I don't really see any info on what PS specs are needed for the cellpro 10 on their site. What would a comfortable output be for a power supply to power the 10?

Decisions, decisions... :confused:

Thanks

-David

[th3tick]

The 10s appears to have a useful feature in that you can set it to limit itself for the available power supply. That said, it says the max value is 25A, so I bought one of the radio shack 25A power supplies for it.

John

[th3tick]

I should also mention I have another of the 25A PSes, and I have two Cellpro 4s and a TP-1010 hanging off it. For charging 6S, you can basically double the output amps selected, as 22.2-25.2 is the voltage range, which is about double that being supplied by the PS. For a 6S 5000mAh pack, I figure 10A to charge, plus the two Cellpro 4s at 5A max each, so 20A out of a 25A PS should be golden.

My plan is to get two of the 10s in the long run. That should be able to charge 4 packs up to 5S at a time, or two larger ones.

I only wish it was a 12s instead of 10s, then I could go up to four 6S packs at a time...

You can't really get "too much" of a power supply, although heat and what it pulls from the wall might be an issue. Finding big ones is harder, and becomes more expensive (although Radio Shack already overcharges for theirs).

John