DX7 - Flightpower EVO TX

[andylinney]

Just got my new tx battery and was wondering if it's ok to charge the evo tx lipo through the transmitter's charging port using a lipo program on my charger.

I can't think that there would be any real problem but thought I'd ask you all what your thoughts and experiences were.

Cheers,

Andy

[SRH990]

Doubtless you will get many posts telling you how you will burn your house down if you try but, to be honest, I do this quite regularly with the lipo in my PCM9XII. As the discharge rate is so slow I tend to balance charge every third charge or so but it's always in balance when I do.

[andylinney]

Doubtless you will get many posts telling you how you will burn your house down if you try but, to be honest, I do this quite regularly with the lipo in my PCM9XII. As the discharge rate is so slow I tend to balance charge every third charge or so but it's always in balance when I do.

I've only got a discharge balancer so I'll hook it up every 2nd charge to keep it in line until the Cellpro arrives...

[barney]

Hi Andy, I'm using one in my 12FG and charge via the charge Jack although it is a 2S Lipo replacing a 6 cell NiMh. It roughly doubled the Tx runtime between charges.

I left the ballancing plug on for fast charging/ballancing as I wouldn't like to charge higher than 0.5amp through the jack. I just set mine at 0.3amp

As for ballancing..In cant see it being that necessary due to the slow discharge/charge rates + the runtime and V display would warn of a problem brewing.

Possibly the thing to be aware of is over disharging with the 3S Lipos as the Alarm may be set to low in the Tx (not that your likely to that anyway) Since Lipos dont have memory problems you can top it off when its convienant.

Brian

[cjcj1949]

There's a lot of misleading information about lipos. Lots of people say it's dangerous to charge over 1C but it certainly isn't. Lipos will blow up if you short them out or charge a 2 cell pack to 12.6v or use a Nimh or NiCd charger and wait for the voltage dip. I've found that balancing on some chargers isn't very good and that cells often sort themselves out with an unbalanced charge.

[andylinney]

Actually bearing that in mind I need to keep an eye on the voltage and not let it get below 10v I guess (3.3v / cell). I hadn't thought of that so thanks!

Is there any way of altering the alarm voltage in the DX7 I wonder?

[cjcj1949]

The real minimum figure is 2.5v per cell. At a few 100ma it shouldn't be a problem. I think the DX7 alarm goes off above that. If you do get a problem don't send the DX7 back with a lipo in it as Spektrum say it is not standard and breaks the guarantee.
Chris

[barney]

Andy, low V problem only if you get REALLY lazy.. Your poss looking at 5-6hrs on the Dx7.

Since the runtime is considerably longer just allows you to charge when it suits you.