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Old 07-31-2012, 10:51 AM   #27 (permalink)
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The other night I borrowed an oscilliscope from work and took a shot at troubleshooting this current sensor issue. I found out the 5V going to the sensor varied a bit, but the vref and output from the sensor were pretty solid (+/- 1mV). I put a capacitor on the 5V input to the sensor and it smoothed things out a bit. I also tried running the arduino off of a 12V battery. Each time the 5V input got a little better, but through the whole thing the sensor output was still very steady.

So, now I am wondering why the arudino is reading a voltage fluxuation on the vref and sensor output pins. According to the serial feedback on the arduino, I'm seeing voltages of 2.519V to 2.539V. The scope showed a pretty consistent 2.513V. So, not only is it showing a voltage fluxuation that isn't there, it is also reading an incorrect voltage.
Current project: A better alternator delete
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