Amp Draw?

[psycho]

Hi Everybody!
Will like to know the current amp draw of a BK120/Feigao540c9XL combo for a G2R, so I can decide which lipos(amps + Cs) that should I get.
Thanks :037:

[Rtsbasic]

What sort of voltage are you planning to run? The more voltage you put through, the higher the potential amp draw, unless you gear down to compensate.

[MetalMan]

Just for a general setup, my thoughts are that 60amps continuous should be minimum.

[BrianG]

I'd go for the max current draw that you can afford and fit (weight and size wise). That way, the voltage drops less under load, you get more runtime, and you don't have to worry as much about how close you are getting to the C rating of the cells.

[psycho]

Well, I am planning to use 6s lipo. Although I could try 5s lipo.I was planning to use the Maxamps 3s 8000 but they weigth around 19 ounces each, which is not to much difference from the 8 cells packs that I am using now, that wheight 22 ounces each. I know it would be more voltage but i want the lees weight possible.:037:

[MetalMan]

How about two 3s 6000mah packs? They come in at 15.6oz. each, which is only a little bit more than the weight of 6 NiMh cells.

[psycho]

Those sound good! Had anyone try those on a similar set up?
I emailed Maxamps and they recomend me the 8000, but i do not like the weight of those.:037:

[natrix]

What is the magic formula for calculating amp draw, or at least a ball park figure?

[BrianG]

You really can't calculate amp draw since there are SOOO many variables and there will be spikes of current flow as you accelerate.

You can either get something like the eagletree systems unit, which lets you record and plot your energy usage, or calculate your average amp draw.

To calculate the average amp draw, just multiply your battery Ah by 60 (to get amp-minutes), then divide that by the number of minutes you ran before the pack was dead. This is the average amp draw. Just remember; the actual draw varies widely during the cycle.

Also, this assumes that you drain the exact Ah rating of battery, which is most likely not true. When you pull heavy currents, the real-world Ah rating will go down a little.

[aqwut]

send it over to me and I'll test it for you with my ammeter.. :) :)