nrthwing

I just upgraded my old 600 mah (Futaba 7 CH) TX battery with a Hydramax 1200 mah. Question, the instructions on the new battery say to charge it 12 to 14 hours at 100 mah. My wall charger that came with the Futaba radio only delivers 70ma. Should I just leave it plugged in longer. I charged about 8 hours and the pack was getting pretty warm so I unplugged it.

Is it ok to use my 70 ma wall charger as I really don't want to buy another charger.

Thanks,
Mike

guver

My Feedback: (325)

If the batt was dead to begin with then at 70 ma it should be around 30 hrs.

Rodney

Your 70 mah charger will do fine. Your first charge should be 600/70 X 1.6 or slightly more than 13 hours to give it full charge. In fact your battery will give you best service (longest life) if you always use the slower charge rates rather than fast charges (1C rate). It will also not hurt the batteries if you should overcharge a slight amount with the slow rate. Check out www.rcbatteryclinic.com for some good advice on how to take care of your batteries.

richrd

I second ALWAYS slow charge Hydrimax.
1200mAH/70mA = 17 hrs plus 40% for losses if dead equals 24 hrs will be max time.
If only disacharged half way then overnite 8 to 10 hours will be standard.
I like what you did when the pack gets warm it's always time to stop.
Rich

guver

My Feedback: (325)

We're a lot of help, 30 hrs.. 13 hrs .. 24 hrs.. [X(][&:]

Rodney

The 13 hours was for a 600 mah battery, the 1200 would be 1200/70 * 1.6 or slightly over 27 hours. It is recommended by most to do the 1.6 rather than the 1.4 times to accomodate the ineffeciencies of the charge cycle although in most cases the timer stated by richrd will suffice.

richrd

We're OK we always agree to disagree I concure 60% over is OK I just stop when warm for an hour so it's earler.
Good part abut C/10 it's not that senistive to the perfect time. 14-16 hrs are good numbers.
But 30 hrs [X(]
[8D] Rich

guver

My Feedback: (325)

As the rate goes down the percentage of "overcharge" must go up. Or the charge effieciency goes down. A 1200 at 70 ma is c/17 and a multiplier of 1.8 - 2 should be used .

17 hrs is the calculated capacity and does not account for ANY losses. [X(] Agree to diagree, I just hoped we helped nrthwing with his app.