HX711 connected to a Wheatstone bridge.

Using Arduino Project Guidance
1

Hello.

I need help to understand how I can use my HX711 op-amp to read voltage through a Wheatstone bridge. I connected a "full-bridge" on a cantilever beam using four strain gauges, and I use the library from:

Unfortunately, I am unable to decipher the raw data, and the library from GitHub is very aimed at weight scales. Is it by the way possible at all to read voltages with this op-amp?

I am new with Arduino and strain gauges. So a stepwise explanation is preferred.

Thank you in advance! :slight_smile:

2

Hi,
Welcome to the forum.

Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html then look down to item #7 about how to post your code.
It will be formatted in a scrolling window that makes it easier to read.

If we start with your code and also a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png, we will be able to give you some meaningful solutions.

Thanks... Tom.. :slight_smile:

3

Thank you!

This is the code i have used:

// Hx711.DOUT - pin #A2
// Hx711.SCK - pin #A3

#include <Hx711.h>

Hx711 scale(A2, A3);

void setup() 
{

Serial.begin(9600);
}

void loop() 
{

float value = scale.getGram();
Serial.print(value);
Serial.println(" mV");
delay(1000);
}

I have also attached a copy of the circuit.

Circuit copy.jpg

4

Hi,
You may have to calibrate your cantilever beam with sample masses.
Have you looked at the data sheet for the HX711 IC?

Tom... :slight_smile: