Don't ad-block us - support your favorite websites. We have safe, unobstrusive, robotics related ads that you actually want to see - see here for more.
0 Members and 1 Guest are viewing this topic.
So, would I be correct to think measuring the resistance between the motor leads and dividing the voltage by that resistance will give me the maximum current the motor will draw?
No this will not work. The reason is because your motor needs to be powered when doing this measurement, which means when you do a measurement you are not just putting leads across the motor, but also across the power source.
Why does the motor need to be powered to measure its stationary resistance?
If I measure the resistance (R) of that coil and then put V volts across it, I can expect to have a current of V/R pass through that coil of wires so long as I hold it stalled, right?
stall current can still be a property of your motor that's important to know.
At 7.2V I wouldn't expect more than about 4A draw (per motor). You wouldn't want to run your motors at stall, anyway. Have you measured the zero load current draw?
Lenz's law wouldn't apply to the stall current, though, which seems to be the worst-case current draw Joe is interested in. I see no reason why Joe's calculation wouldn't be valid for stall current.