What chips/elements should be used to measure voltage/current/resistance?

Question

Arduino

Bottom line:
The Arduino Uno board should measure voltage, current and resistance in the circuit. What items do you recommend? What to read anyway?

Answer 1

Roughly, you can say this: you can only measure voltage , and do this with the help of an ADC.
If you need to measure the current, we pass it through the shunt and measure the voltage on the shunt.
If you need to measure the resistance, we skip a known current and measure the voltage . Or we apply a known voltage to 2 series resistances (known and unknown), and - again - measure the voltage on the shoulder of the resulting divider.
There are specific methods for very large or very small currents / resistances / voltages, but I think this is not your case.

Answer 2

I agree with the previous speaker in general, I want to add that there are special microchips for power meters. For example, INA219 (from what I remembered right now) - measures the total voltage, the voltage drop across the shunt, based on these data, it can calculate the current and directly consumed power in watts. Works on the I2C interface.

Answer 3

There is another interesting method for measuring resistance: you can turn on the capacitance in series with the measured resistance and apply a pulse to this differentiating circuit. The voltage from the resistor can be applied to the arduino leg, measure the pulse duration and convert it into resistance. The accuracy is not high, but you can get by with only I / O inputs.

Answer 4

You can also use a Hall effect current sensor to measure current. For example www.kosmodrom.com.ua/prodlist.php?name=sensortok&page=0