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Old 04-01-2010, 01:28 PM   #1
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Default is mixing 2s 20c with 3s 25c bad?

I am trying to see if mixing my 2s 20c 5000mah blue lipo and a zippy 25c 3s 5000mah packs will damage the speed controller or give me erratic responses. I am really wanting to get a match to my 3s but hobbyking is out of stock and i can't find someone to let go of one that does have one haha.
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Old 04-01-2010, 08:30 PM   #2
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If you wire them in series you should be fine and end up with 5s 5000mah, if you wire them in parallel I think you may run into issues with voltages, not positive but I think you'd end up with a 2s 10000mah battery then, not entirely positive on that one.
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Old 04-01-2010, 11:02 PM   #3
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Originally Posted by tromoly View Post
If you wire them in series you should be fine and end up with 5s 5000mah, if you wire them in parallel I think you may run into issues with voltages, not positive but I think you'd end up with a 2s 10000mah battery then, not entirely positive on that one.
yeah the 5s is what i am aiming for. I am just worried about the different c ratings.
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Old 04-02-2010, 06:22 AM   #4
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I don't think it will damage the esc, but I'd be more worried about damaging the lower C rated lipo. The usual advice is to match the lipos even down to their useage before running them in series.

Lower C rating may mean higher IR in that lipo and more heat from that lipo. If you do this, pay attention to lipo temps and avoid running close to the lvc until you know there's not going to be issues. The testing I've seen on teh HC lipos has showed C ratings may be conservative so there may be even more diff in C ratings than label say.
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Old 04-02-2010, 12:01 PM   #5
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Originally Posted by Duster_360 View Post
I don't think it will damage the esc, but I'd be more worried about damaging the lower C rated lipo. The usual advice is to match the lipos even down to their useage before running them in series.

Lower C rating may mean higher IR in that lipo and more heat from that lipo. If you do this, pay attention to lipo temps and avoid running close to the lvc until you know there's not going to be issues. The testing I've seen on teh HC lipos has showed C ratings may be conservative so there may be even more diff in C ratings than label say.
good info i will definitely watch temps. I have a crap 20c 2s i can throw in there to test with that i don't run in any of my cars and runs warmer then the others. If that one does fine i am 99% sure that the others will do fine. I will post my results here when i test it in about a week when i get my savage conversion up and running thanks for the info.
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