Raspberry Pi and Weight Sensors

Hello, I wanted to quickly check the compatibility of the following parts before I purchase them.

Goal: To use weight sensors for a scale-like function with the Raspberry pi 3b+.

Parts I want to use:

SparkFun Load Sensor Combinator

Load Sensor - 50kg
(Load Sensor - 50kg Australia)

Raspberry Pi 3 Model B+

SparkFun Load Cell Amplifier - HX711

And Maybe some Jumper cables.

If someone can let me know if these parts are compatible with one another, I would greatly appreciate it. Thank you.

1 Like

The HX711 should be compatible with the Pi 3B+, 2.7 to 5V range, Pi GPIO pins should work direct to HX711 Data & Clk. (Pi GPIO 3.3V logic). A google search lists Python & C++ libraries on Github for the Pi (no idea if they work though, dont have a HX711 to test).

But, The Sparkfun board has 4 wires to connect to the load cell; the load cell listed seems to have only 3 wires. The link to the specifictions does not work, both on Core Electronic & Sparkfun web site. Until I had a good understand of why there is only 3 wires and can I use them with the HX711, I would be hesitant to buy. This device has 4 wires and probably would work but is only 5kg.

Maybe contact Sparkfun to see if you can get the specifications.

EDIT: A little more googling and I think you would need 2 or 4 of the 50kg load cells or 2 resistors to connect it to the HX711. The load cell is just 2 resistors, one +ve strain one -ve strain.
This video shows you how.