Charging NiMH's
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Charging NiMH's
I just noticed now when looking at the Futaba RX/TX charger, it says to only use on Ni-cad cells and the output shows 4.8v @ 50mA. I've a couple 6v 1800 NiMH receiver cells and only changed one of them once with some attention. The caution on the charger says not to use any other types, does anyone know if it's safe or fine to charge the MH's with this charger? I'm not sure if it's charging to full capacity since it shows 4.8v output.
The charger is a class 2, model FBC-8B(4), if anyone else has one and does the same, LMK.
The charger is a class 2, model FBC-8B(4), if anyone else has one and does the same, LMK.
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Charging NiMH's
The Futaba wall wart will not charge 6V packs sufficiently.
You will need to invest in a charger capable of doing NiMh packs.
Just search in this forum on chargers. I have the Dymond super Turbo myself.
You will need to invest in a charger capable of doing NiMh packs.
Just search in this forum on chargers. I have the Dymond super Turbo myself.
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Ni-Cad--->NiMH
I readed in RC Car Action magazine says that it's OK to charge NiMH with Ni-Cad charger as long if it doesn't get hot. When NiMH battery get warm, that mean it's done charging and if you let it get real hot, it could damage the NiMH battery. So that mean you have to keep an close eye on it.
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Charging NiMH's
Yup, I let it charge for approx 10 hours and afterwards measured the voltage which shows 5.84v which is good enough. The pack didn't even get warm so I suppose it was close to done. Them guys at RC Car Action know alot, I've read their mags since '91 and have seen alot of great tips, tech Q/A's, and now the Robinson Racing section which rocks.
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Charging NiMH's
5.84 is quite near empty for a 5 cell pack. The 4.8 charger does not have a high enough output voltage to charge a 6 volt battery.
A cell fresh off of charge is typically 1.45 volts. Your pack should read around 7.2 fresh. When a load is put on the voltage will quickly drop to around 1.25 per cell
An 1800mah pack will never get warm off of a Futaba wall wart even if you leave it on for a month.............
I charged 4 cell NiMh packs off of my wall wart for quite a while until I bought a better charger/cycler
A cell fresh off of charge is typically 1.45 volts. Your pack should read around 7.2 fresh. When a load is put on the voltage will quickly drop to around 1.25 per cell
An 1800mah pack will never get warm off of a Futaba wall wart even if you leave it on for a month.............
I charged 4 cell NiMh packs off of my wall wart for quite a while until I bought a better charger/cycler
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Ah so it is right about the voltage showing higher than specified voltage then. I measured on my other 5 cell and it showed about 7 volts and i said "can't be right"... OK so I'll plug it in another night and see how much further it gets tomorrow.
#7
Charging NiMH's
Actually thats right! They do go over when they are fully charged. But they quickly drop to about 6 and stay there until they die and then drop to about 5 which is when theyre dead.
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