Hi I have just received the INA3221, and just wanted to make sure I connect everything up correctly so I don't blow anything up.
I was looking to place my 100A / 75mv shunt on to the negative terminal of my battery bank and the negative of the Inverter to be connected to the shunt (read somewhere that it was safer to connect it to the negative side).
so I aim to Cut SJ3 INA1+ JP2 / 1 be connected on to the shunt on Inverter side INA1 - JP2 /2 be connected to the shunt battery negative side
do I need to connect anything else was not sure if I needed a common ground from the battery bank to the INA3221 and if the max voltage of 29V could be a problem?
And just to clarify the connections to the Pi
Power 3.3V (GPIO/1) GND GND (GPIO/6) SCL I2C1_SCL (GPIO/5) + 10k Resistor to GPIO/1 SDA I2C1_SDA (GPIO/3) + 10k Resistor to GPIO/1
Hi Can I add an inline resistor or something to make the voltage down to a safe level and still get fairly accurate results from it, I know I will need re calibrate the output results in code but that should not be to much of a problem.
also if I connect the shunt to the positive terminal and connect the common ground between the 2x 12v battery's with a diode this will then just give me a max of 14.5 V or will this still fry the circuit
Last Edit: Jul 13, 2017 16:40:17 GMT -8 by robyice
ok worked out the problem your manual is a little confusing.
where you put GPIO/5 I connected this to GPIO05 and that's pin 29 and in fact you mean pin 5 and where you have GPIO/3 I connected that to GPIO03 and that's pin 5 when I should be connecting it to pin 3, changed all this and now it all works.
with the shunt measuring the Negative terminal it is happily keeping an eye on the load of the 48v battery bank, obviously its not possible to see the V and watt as this would require it to be connected to the positive terminal and would put to many V into the ina3221