Hello,
Regarding the current sensor,
I played with the ACS712 a few months ago, and if I remember correctly, it outputs mv RMS and has a DC component of VCC/2. So you have to remove the DC component from the sensor output, then rectify for DC. I believe this sensor is really intended as a replacement for a current transformer. Also, there are vendors that sell pre-made ACS712 circuits with increased sensitivity like the one your trying to make. Check SPARKFun. Last time I looked, they cost about $10 USD. So...the short story....The ACS712 is not an RMS-to-DC converter.
Regarding the Voltage Sensor,
You haven't said if the ADC is reading DC or AC voltage.
But if the voltage is AC, you'll need to design an AC coupled Op Amp buffer/level shifter frontend for the PIC. The Level shifter would shift the AC voltage above 0vdc so you'll get the full resolution of the PIC. And you will need and Rail to Rail OP Amp to do that.
Hope that helps....
eT
Regarding the current sensor,
I played with the ACS712 a few months ago, and if I remember correctly, it outputs mv RMS and has a DC component of VCC/2. So you have to remove the DC component from the sensor output, then rectify for DC. I believe this sensor is really intended as a replacement for a current transformer. Also, there are vendors that sell pre-made ACS712 circuits with increased sensitivity like the one your trying to make. Check SPARKFun. Last time I looked, they cost about $10 USD. So...the short story....The ACS712 is not an RMS-to-DC converter.
Regarding the Voltage Sensor,
You haven't said if the ADC is reading DC or AC voltage.
But if the voltage is AC, you'll need to design an AC coupled Op Amp buffer/level shifter frontend for the PIC. The Level shifter would shift the AC voltage above 0vdc so you'll get the full resolution of the PIC. And you will need and Rail to Rail OP Amp to do that.
Hope that helps....
eT
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