What is the voltmeter charging effect

Influence of 2-pole and 3-pole voltmeters and Arduino voltage sensing on the circuit

Sounds like you're concerned about what's called a loading effect. This occurs when you add another component (Arduino or voltmeter) to a circuit. Essentially, electricity is drawn from the circuit. High-end measuring devices have a so-called high input impedance. These meters draw negligible current from your circuit. The bigger your load, the more current a meter draws. If you have a very large resistance and you are reading the voltage with a voltmeter with a relatively small input resistance, then all of the current wants to flow through the small resistor, also known as a voltmeter. For more information on the current distribution, see "Loading Effect".

I have more experience with the Arduino for voltage measurement, so I'll talk a little bit about my knowledge with it.

First off, it's not too difficult to program an Arduino to read a voltage. However, there are some limitations. It can only read voltages up to 5V (there are ways to work around this) and I've found it to be not too accurate (8-10 bit resolution). On the other hand, it depends on how accurate the measured values ​​should be. The Arduino didn't seem to have much of a loading effect (I compared the results from a voltmeter). The hardest part is having a means of showing your tension reading on a screen. You can buy small screens with Arduino libraries, but these can be problematic. Most of the time I spent making the screen look presentable.

The voltmeter module definitely seems like the easiest way to go. I am not sure what loading effects they will have. I'm sure that is different between the models. If you're looking for a quick way to go, a voltage module can do the trick.

I would personally recommend buying a voltmeter from your local hardware / electronics store. They have good input impedance and can be cheap.

Hope I was a little helpful!

Good luck Josh

Zoltana Maximus

Thank you Josh! I looked up the loading effect and now I have a better idea of ​​what to avoid. It's good to know that either of these ideas will likely work with no significant impact on the circuit as long as I can ensure a high input impedance on the voltmeters.