I am looking at building a scale with 4 of these. Load Cell 1KG 5KG 10KG 20KG HX711 AD Module Weight Sensor Electronic Scale Aluminum Alloy Weighing Pressure|Cable Winder| - AliExpress and 1 x HX711.
How would I wire the load cells to the HX711 as each load cell is 4 wire?
You can’t build a scale with different span load cells on it .
If you use two hx711 amplifiers you can wire 4 load cells and calibrate each separately , then calibrate the scale as one .
You need to then check that the scale reads correct if the load is off Centre ( off centre loads can also create side loading which affects the readings or causes binding ) .
You will need 4 HX711's. It is likely possible to Multiplex the sensors but that may be more complex than 4 HX711 boards.
Note the HX711 board has two input channels. Unfortunately they cannot be set to the same gain so it would be a poor design to force 1 channel to be at an undesirable gain.
Before you go too far, look at how this type of load cell has to be mounted. You will need brackets off the top and bottom to keep the mounting ends parallel when loaded. Likely difficult from my description but I'm sure a quick google will find a better description (with photos)
"Connect all HX711 units to share a single clock line, and plug each data line from the HX711 to a different pin on the Arduino"