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Originally Posted by TonzOFun
Our drive has always taken way too much power, dropping our voltage from 12.9 (after sitting off the charger for 15-20 mins to burn off the surface charge) to 7.9 while trying to turn (doesn't seem to matter how far the joysticks are pushed), but it is only dropping to around 10 when going full power forward or back.
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I can infer that you are doing tank style turning with sticky tires or treads. This is the inevitable result of this type of steering. Omni wheels would help or center trucks on a tread system that are slightly lower than the front and back.
For anyone reading this post, 12.9 volts out of this battery is a temporary reading following charging. Within seconds of a load being applied, this voltage will fall to 12 volts nominal or 2 volts per cell. With a battery nominal internal resistance of 11 mohms, a four volt drop indicates you are drawing in excess of 350 amps during a turn. ( if you were looking with a scope you would see spikes exceeding that amount.) With a four motor drive you are near stall on all motors. (which coincidently is what happens when you turn tank style with sticky tires or treads.) For reference, the RC drops out at just under 8 volts and runs off the backup until the main power rises to more than 8 volts. (This is a design tradeoff to get a regulated 5 volt rail from the main battery. The regulator requires at least two volts higher on the input than the output to function plus the reverse polarity protection diode.)