Is this circuit right according to the diagram?

Hey guys,

I am new to circuitry and I need help verifying if my circuit is right according to a wiring diagram. The circuit is for a weight scale with the HX711 ADC amplifier.
Please refer to the following link for the project on Instructables. Please see the attached pictures and code that allows one to calibrate the sensor. I am supposed to get a relevant weight reading but all I get are zeros :frowning: .

I am unfortunately a noob at this, but hoping I can get some help and advice from experts like you all.
Kind Regards
V

/*
 Setup your scale and start the sketch WITHOUT a weight on the scale
 Once readings are displayed place the weight on the scale
 Press +/- or a/z to adjust the calibration_factor until the output readings match the known weight
 Arduino pin 6 -> HX711 CLK
 Arduino pin 5 -> HX711 DOUT
 Arduino pin 5V -> HX711 VCC
 Arduino pin GND -> HX711 GND 
*/

#include "HX711.h"

HX711 scale(5, 6);

float calibration_factor = 48100; // this calibration factor is adjusted according to my load cell
float units;
float ounces;

void setup() {
  Serial.begin(9600);
  Serial.println("HX711 calibration sketch");
  Serial.println("Remove all weight from scale");
  Serial.println("After readings begin, place known weight on scale");
  Serial.println("Press + or a to increase calibration factor");
  Serial.println("Press - or z to decrease calibration factor");

  scale.set_scale();
  scale.tare();  //Reset the scale to 0

  long zero_factor = scale.read_average(); //Get a baseline reading
  Serial.print("Zero factor: "); //This can be used to remove the need to tare the scale. Useful in permanent scale projects.
  Serial.println(zero_factor);
}

void loop() {

  scale.set_scale(calibration_factor); //Adjust to this calibration factor

  Serial.print("Reading: ");
  units = scale.get_units(), 10;
  if (units < 0)
  {
    units = 0.00;
  }
  ounces = units * 0.035274;
  Serial.print(units);
  Serial.print(" kg"); 
  Serial.print(" calibration_factor: ");
  Serial.print(calibration_factor);
  Serial.println();
  delay(500);

  if(Serial.available())
  {
    char temp = Serial.read();
    if(temp == '+' || temp == 'a')
      calibration_factor += 1;
    else if(temp == '-' || temp == 'z')
      calibration_factor -= 1;
  }
}

Where is the schematic and why isn't the
filename "SCHEMATIC" ?

Yes, we can tend to be hostile to new users on theses forums. In general, Fritzing pictures are not welcome because they are not what experienced engineers are used to- schematics. (I don't care what Fritzing calls them, the pretty pictures are not schematics). For complex circuits, pretty Fritzing pictures are really difficult to follow. But this project is relatively simple and there is no need to draw a real schematic.

If you have wired the sensor and amplifier as shown in the Fritzing drawing, and loaded the sketch in the tutorial, it should work.

So, you are getting all zeros? Then your load cell is calibrated. What's the problem?

Hey guys,

Sorry, I was not familiar with how things work on here....
When I post next time I will take your advice.

As per the problem, when I load the sensor, there are no weight readings. Which is confuses me as to what I am doing wrong. So my immediate thought was the possibility of the circuit being wrong.

According to the Fritzing diagram, does the circuit look right?

Kind Regards
Vamshi

There is a post at the top of the forum on how to use the forum, prudent to review it

https://forum.arduino.cc/index.php?topic=149015.0

Most of the others that help here are way ahead of me, but when I look at your pictures I just see many colored spaghetti that is tough to look at let alone trouble shoot and requires going back and forth between pictures.

A regular schematic even if hand drawn is much easier to understand than the Frizzy Thing and is what most experienced people are used to using, I just threw out a beginners tutorial because they insisted in using the Frizzy Thing with no real schematics.

Good luck with your project, literally centuries of experience here willing to help, and if you make it easier for them you get better and quicker help.

Sorry, I tried but I just can't follow your photos of spaghetti to check your wiring.

Fritzing actually has a "schematic view" option. It's still often looking pretty horrible (with overlapping lines and so), but far less horrible than the breadboard view. Makes the thing much easier to follow already, and actual component values are given there as well.

But indeed nothing beats a real schematic. Even hand drawn is usually better than whatever Fritzing spews out.