Esp32 Photovoltaic current/voltage measures

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1

Hi all.
I need to measure power (voltage, current) on a photovoltaic cell (about 12v, 10A).
I read about ACS712 30A and INA226 or INA332.
I didn't found a INA226 with a shunt resistor of 0.008 Ohm (or less) on board
I don't know about ACS712 precision.
May anyone help me?
Thanks.

2

Described in the ACS712 data sheet.

The INA260 is a much better choice.

3

Thanks,
This seems to be equal to INA260:
https://it.aliexpress.com/item/1005005376923466.html

4

Something wrong.
Picture shows 0.01 ohm resistor but description say +/-20A
With a 0.01 the range would be+/-8.19A
Not equal the the 260

5

The INA226, even if genuine, is similar to, but not the same as the INA260.

Hint: when posting links on a public forum, remove your personal tracking information, which is all the junk after the "?".

This is all you need: https://it.aliexpress.com/item/1005005376923466.html

6

Oh, thanks!

7

yes, I noticed, the description is wrong.
This ina226 is similar to ina260 for current range.
I need something with 0.008 Ohm shunt for 10A current max..

8

Unless you design and build your own there are not many choices.
You might consider this product:

Or solder your own shunt resistor on one of the INA226 boards.

9

The INA260 module linked in post #2 does exactly what you require.

10

can i solder a shunt resistor on INA226 without prooblem?
In any case the parts (ina226 + shunt or ACS724) are a bit expensive..

11

I have no further suggestions.

12

1718983050036
17189830500361920×936 33.8 KB

if I have two panels and I want to measure the power generated, can I measure only the voltage with for example a 10k trimmer (which acts as a load) and have P=v^2/R?

13

Yes, I'm keeping it as a solution for now.
Thanks

14

So no more 12V, 10A requirement??

15

This is an example case. There are more than 2 panels

16

If your goal is to measure power with small currents, then sure you can use a 10K resistor.
You can use any value you want.

17

Yes, I use a trimmer to divide the input voltage to the esp32 (3.3v) which measures the voltage, but I can use the same trimmer as the photovoltaic load and calculate the power as v^2/R
It's correct?

18

Not sure why you would want to make such a mesurement but yes it is correct.
R would be the resistance between the wiper and ground.

19

cause i want to measure the power that can be generate all panels

20

I only have one doubt.. the voltage of the panels in parallel will be around 6 v, regardless of the number of panels. If I calculate the power as v^2/R I will always have the same value.. Maybe is necessary to measure the current i