2023-03-07, 12:00 AM
(2023-03-06, 11:48 PM)HeviiSailor Wrote: Hi Jason,
I'm in the middle of a rather length shopping list for many electronic goodies. While I had watched your video yet again to make sure that I hadn't missed anything, I actually did find something which I hadn't noticed earlier: You've connected your shunt on the positive side of the battery. Can you explain please why you've done it like this? I've always understood that shunts should be on the negative side. Nevertheless, I'm not too old to learn something new!
the INA219 is a high side (positive side) DC current sensor which is good to 26V, where some of the others available are not capable at that voltage and therefore they need to be on the low side (negative side). The ones on the negative side need a second sensor to report the battery voltage whereas this does not. It does need the same 0V reference though, so when you are testing on the bench, you need to tie the battery ground into the ESP32 ground, even if you are powering the ESP via USB from another source - ask me how I know that? Lol!