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charging nimh battery packs

Old 08-31-2016, 05:41 PM
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jtsmash
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Default charging nimh battery packs

Using a turnigy accucell 6 to charge 6v packs turnigy 2300 nimh. My question is what would be the best delta peak setting? Its default is 4mv. I question whether my packs are being fully charged. I go fly 4 times on a .46 size extra with metal gear servos. When i put it on the charger at 0.3a nimh setting its only putting in 350mah?? To me that seems too low for 4 flights I fly fairly aggressive.
Any suggestions would be great.

Last edited by jtsmash; 08-31-2016 at 05:44 PM.
Old 09-01-2016, 02:49 AM
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Sounds about right, we used to fly that same size/type plane with a 600mah NiCd pack back in the day just fine getting 4-5 flight before needing to recharge.

If you don't think the battery is fully charging,, do a charge/discharge cycle test a couple times

good luck
Old 09-01-2016, 04:16 AM
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Originally Posted by scale only 4 me
Sounds about right, we used to fly that same size/type plane with a 600mah NiCd pack back in the day just fine getting 4-5 flight before needing to recharge.

If you don't think the battery is fully charging,, do a charge/discharge cycle test a couple times

good luck
You most likely are correct, but I had the same experience as the OP. When I cycled my packs, I found that they weren't fully charged. I'm sure thatthe issue is in the programming of the charger, but I can't figure it out.

I get around the issue by charging my packs on my Accu Cycle.
Old 09-01-2016, 04:52 AM
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Thanks guys, next question then would be what voltage to discharge to ? say a 6v nimh battery. what would be the cut off voltage to see how many milliamps are left?
Old 09-01-2016, 05:40 AM
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Unless you are an expert and are doing something way out of the ordinary, WHY NOT USE THE FACTORY SETTINGS?

Sorry about shouting but I firmly believe in RTFM - read the f------ manual.
Old 09-01-2016, 05:54 AM
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Originally Posted by rgburrill
Unless you are an expert and are doing something way out of the ordinary, WHY NOT USE THE FACTORY SETTINGS?

Sorry about shouting but I firmly believe in RTFM - read the f------ manual.
As stated the factory setting on discharge is 4.2V. To me that is way too low for a 6v 5 cell nimh pack. that would discharge the cells to below 1v each. Im thinking between 5.5 - 6v but not 100% sure what voltage would be considered the pack fully drained. Just wanted some advice on what others are using.
Obviously, if it was in the manual I wouldn't be asking......
Old 09-01-2016, 06:28 AM
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For safe RC flying capacity it's 1.1 volt per cell. Anything lower would put you in the region where the voltage is collapsing too fast to be of any use. Also try opening the peak sensitivity to something higher per cell. I use 20mv/cell. Dan.
Old 09-01-2016, 08:56 AM
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Originally Posted by TomCrump
You most likely are correct, but I had the same experience as the OP. When I cycled my packs, I found that they weren't fully charged. I'm sure thatthe issue is in the programming of the charger, but I can't figure it out.

I get around the issue by charging my packs on my Accu Cycle.

I've gone away from the AA size nimh for the same reason,, "False Peaks", I lost a plane a couple years ago because I was watching voltage not capacity,, these were the Hobbico battery packs Tower sells,, they worked great for a few years, then after the crash i tested them and found the would peak fast,, when I cycled them, I found they only has 2-300 Mah capacity,, as soon as you put a load on them,, they would go dead fast. This was after both fast charging and after using the wall charger overnight.. In my case It was the packs not the charger

I only use A123 packs now as they are designed for fast charging


good luck
Old 09-01-2016, 09:18 AM
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Thanks guys for the information. Thats what im trying to avoid, although i do not fast charge the nimh packs i had a close call on the ground thankfully, but trying to avoid any future problems lol. the packs are new this year but Im leaning toward just replacing with A123's and using regulators.
I will try bumping the delta peak sensitivity on the charger, mabye up to 7mv , then go fly, come back and discharge to 5.5v and see what kind of capacity is remaining / put back in.
Old 09-01-2016, 09:39 AM
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jt, you're doing all the right things especially checking the capacity of your battery pack before you use it. Most guys don't. You should also be doing some test to determine the current consumption you model uses when you fly. LiFe batteries are not what they are all cracked up to be. Check this thread and see their weakness. Regulators should be avoided because the are just one more single point failure and we already have enough of them. Dan.

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