Using 2 ina219 in a 3 output power supply

Hi, I have a linear triple output power supply. I want to send the data over to my pc via serial module using arduino nano. I have a wiring question.
I want to monitor 2 of the three outputs of this power supply it has separate bridge rectifiers for each output and well the grounds aren’t connected. So in the wiring of multiple ina219 I find that the grounds are connected to one i2c buss how can I completely separate each i2c buss ( it to my understanding that some of the input/output can be switched as i2c) but I’m not sure about the issue with ground. Thanks I’m advance for you help.

There are I2C isolators, some even have a built-in transformer to give a isolated 5V as well.

Can you make a drawing of the project ?
You could put a Arduino at each power section and transfer the data wireless. Perhaps with a Arduino-compatible board such as the ESP32.

What power supply is it ? Is there something smart inside that already measures the current ?

I’m sorry I forgot to upload my hand drawn sketch I will upload tomorrow. It’s a old topward 6306 which I’ve done some repairs on and didn’t want to purchase a rigol. I wanted to update the topward with either usb or serial. I saw some i2c isolators but I was wondering if it would interfere with the accuracy of the measurements. I’ve never used the esp32
I see that it has better resolution for these ina219. How the programming on this ? Is it similar to arduino ? I’m gonna watch some tutorials on these items

The I2C bus for the INA219 is a digital interface, the analog input is not used and a isolator does not interfere with the values of the measurements.
The ESP32 can be used with the Arduino IDE. You can start here (see the list on the left side): https://randomnerdtutorials.com/getting-started-with-esp32/

Ok I decided to go the route you suggested. here is the schematic I have drawn with the esp32. I also can do serial over wifi. So there’s no direct connection to my PC
May 13, Doc 2.pdf (151.8 KB)

Your picture as a picture:


How are the ESP32 boards powered ?
When the power outputs are not connected, then there are more than one GND. I don't see that in the picture.

A NTC is often connected with one leg to GND.
A 10k NTC is used with a 10k resistor. That gives the maximum accuracy at 25°C. A lower value of the resistor sets the maximum accuracy at a higher temperature.

A mosfet does not need to be 1k to keep it off, 10k or 100k is often enough. You could add a resistor of 1k before the gate to avoid current peaks from the ESP32.
Where is the flyback diode over the fan ?
Are you sure that the mosfet should empty the capacitor in a single blast ?

The fan motors are brushless I thought brushless don’t need fly back.

I have these leftover from another project so I was going to use 2 of these:

https://www.ti.com/lit/ds/symlink/lm317.pdf?ts=1620898689485&ref_url=https%3A%2F%2Fwww.google.com%2F Or 1205 which I have

Ok I will change the resistor to 10k and add a 1k to pin of esp 32. The cap reduces noise in the fan it makes a weird noise without it