I had a few questions here about how to read some voltages but never made it work. Detecting 110V DC
Those voltages go from some 70V to 200V. As I haven't access to the system, my work was based on the data I get from the guy I am supposed to make this project. But it is not DC at all. It is AC, and it is as close to a 110V AC as possible, but still not exactly. I made a few measurements and get some 70V - 140V AC, but most readings were around 110V AC.
The problem is how to read variable voltages on a system which I should monitor, but not mess up in it at all. I should only take a two wires and see if there is voltage in it. Finally, I get some spare board of the system to see how they made it. It has been made with my initial approach, but with some additional components.
This is my 50 cents based on their design:
As you can see, they used a Schmitt trigger. I have never used this IC and have little or no experience with it. The other components are familiar. They used here 814 optocouplers, that is why I had bad readings, I used 817 optocouplers.
Question is, how to read it with Nano I attached? My guess is when there is a voltage, I will get some kind of LOW value. But, checking some solutions on the internet, I see some used it as an interrupt. That is why I tied it with the pin 2 on the Nano.
As I said in the topic I mentioned above, I don't have access to the system as much as I would have to. It is some kind of complicated.
I haven't made this project yet, came here first to check am I on the right track.