Please help - Overlander RC6 Charger

[JamieB76]

Hi Guys,

I have bought an Overlander RC6 and despite reading the instructions have no idea if what I am doing is correct.

I have a 7.2v nimh 2400 mah pack which I want to charge, discharge and cycle but am not 100% sure of the settings. Can you help?

So for charging I charge at 2.0a I have set the mah cut off to 3000 mah, apparently the charger should cut off before then any way. Am I correct to think I just press the start with these settings and it will charge? On the top right of the screen it says Man, I assume for manual. Is there a way to change this to auto? It looks like there is in the instructions but mine won’t change no matter what options I press.

For the discharge settings, I try to discharge at the max setting of 1.0a but this normally defaults to around 0.7a. is that normal? What should I set the discharge min volts to? If it’s 0.9v per cell that’s total 5.4v correct? I have read conflicting things about this so I’m confused. I have also read 7.2v!

For the cycle setting I just had it set up for well over an hour and a half on discharge and it was still going when I finally gave up and wrote this. How long should this 7.2v take to discharge from a full charge and run through a cycle on this charger? The instructions say to not leave the charger but at this rate I will be spending all day with the thing.

I am going to move on to lipo but want to learn how to charge a basic battey before moving onto something more technical.

I would genuinely appreciate any help you can give.

thanks.

Jamie

[Andrew Twigger]

Hi Jamie,

If you're charging NiMH batteries, you'll want more like 4-5amps. When these cells were the latest technology, it wasn't unheard of for people to charge them at 10amps or over, but that is dangerous and I wouldn't recommend this.

That charger only discharges at a maximum of 1amp, which will be why it is taking so long. It would be quicker to put them in your car and discharge the bulk of the power that way (although I appreciate this may not be practical). Also, if you do this, don't let it go too flat as you'll risk going lower than 0.9v per cell. Then put them on your discharger after that to get them to a more accurate discharge voltage.

[JamieB76]

Hi Andrew,

OK cool, sounds like I am sort of doing things correctly. So cycling is a very long process with this charger. I think I will do as you suggested and just run the battery.

Its been on the shelf a while so may just get another and then the lipo's sooner than later.

thanks

Jamie

[Ashlandchris]

On a second point, I'd just go straight to lipo and not worry about the Nimh batteries. Yes, the chemistry of lipos is more complicated, but the use and charging of the batteries is much easier and gives much more use.
For lipos stick to the 1c charging and ideally always balance charge (sounds complicated, but isn't).
Back when I used to race we used nicads and charging just meant plugging into a resistor and heat sink. Sounds easy, but lipos give so much more life that all the old technology just feels a waste of time now!!