AverageGuy
New Member
I am starting to work on a project, or the idea of a project, to sense the current draw of a 12 DC motor. My thinking is to add a small shunt in the negative lead of the motor and use a microcontroller with an ADC to read the voltage drop, but I was a bit concerned about using an ADC at the extreme range. I wouldn't want to drop the voltage more than a few hundred millivolts so will an ADC read down to the rail? I don't necessarily need accuracy, just repeatability.
A second related question is about controlling the motor. I need to turn it on/off. It draws about 8 amps. I'm toying with using a 2n3055 since I've got a couple around, but wonder if there is something else out there that would do a better job? I know a relay would work but I'm most concerned about how much amplification I'd need to drive either solution.
Thanks,
Jim.
A second related question is about controlling the motor. I need to turn it on/off. It draws about 8 amps. I'm toying with using a 2n3055 since I've got a couple around, but wonder if there is something else out there that would do a better job? I know a relay would work but I'm most concerned about how much amplification I'd need to drive either solution.
Thanks,
Jim.
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