ukd555The amp rating is meaningless unless the watts can back it up. That is what is important in a charger. It states 2s-4s, a 4s pack will want to charge at close to 16 volts.
The electrical math says the volts divided into the watts will give you the amperage rate. 40 / 16 =2.5. I don't know if you tried, but a straight charge on a 4s pack like an ebuggy pack(5000-6700 mah) will take close to a couple hours at that rate. That isn't a balance charge, which is really what should be done each time. You can add another hour or more for that. Since this charger maxes at 3 amps any pack over 3000 mah (3 amps) will have to be charged at a less than 1 C rate also. Most 2s car packs are 4000-5000 mah
It seems this charger is more in line for charging drone packs which are typically a lot smaller in capacity.
It seems this charger is more in line for charging drone packs which are typically a lot smaller in capacity.