Tutorial to Interface HX711 Balance Module With Load Cell

61,236

69

10

Intro: Tutorial to Interface HX711 Balance Module With Load Cell

Description

This module uses 24 high-precision A / D converter. This chip is designed for high-precision electronic scale and design, has two analog input channels, programmable gain of 128 integrated amplifier. The input circuit can be configured to provide a bridge voltage electrical bridge (such as pressure, load) sensor model is an ideal high-precision, low-cost sampling front-end module.

Specification

  • Two selectable differential input channels

  • On-chip power supply regulator for load-cell and ADC analog power supply

  • On-chip oscillator requiring no external component with optional external crystal

  • On-chip power-on-reset

  • Data Accuracy: 24 bit (24 bit analog-to-digital converter chip)

  • Refresh Frequency: 10/80 Hz

  • Operation supply voltage range: 4.8 ~ 5.5V

  • Operation supply Current: 1.6mA

  • Operation temperature range: -20 ~ +85℃

  • Demension: Approx. 36mm x 21mm x 4mm / 1.42" x 0.83" x 0.16"

Step 1: Material Preparation

In this tutorial, you will need :

1. Arduino Uno Board and USB

2. HX711 Balance Sensor

3. Load Cell (can be any weight of load cell ie 20KG, 60KG or 100KG)

4. Male Female Jumpers

5. Crocodile Clip Wires

5. Arduino IDE

Step 2: HX711 Pin Description

Step 3: Load Cell Wire Connection

The four wires coming out from the wheatstone bridge on the load cell are usually :

  • Excitation+ (E+) or VCC is red
  • Excitation- (E-) or ground is black
  • Output+ (O+), Signal+ (S+)+ or Amplifier+ (A+) is white
  • Output- (O-), Signal- (S-)+ or Amplifier- (A-) is green

Step 4: Hardware Installation

HX711 to Arduino Uno :

  • VCC to 5V
  • GND TO GND
  • SCK to D5
  • DT TO D6

Load Cell to HX711

  • E+ : RED
  • E- : BLACK
  • A- : WHITE
  • A+ : GREEN

Then, connect your Arduino Uno Board to your Computer via USB.

Step 5: HX711 Library

Communicating with the Balance Module requires a driver for the HX711 sensor. The simplest way to install the driver is to download the HX711 library. Download the ZIP file below > Open Zip File > Extract to your Arduino Uno Library folder. Refer the image above for your references.

Step 6: Sample Source Code

Download the sample source code below, open and upload this sample source code into your Arduino IDE.

NOTE : You can change your calibration factor before uploading the code OR you can adjust it later in the serial monitor box since the code allow you to add and substract the value of calibration factor.

Step 7: Serial Monitor

When you has succesfully uploaded the sample source code into your Arduino Uno Board. Open Serial Monitor and it will show u as shown in the picture above.

Step 8: Result

when the serial monitor give u a value for reading, it means that u has succesfully interface your load cell. Now, you can set your own calibration factor by adjusting the value using the '+' or 'a' to increase the value OR '-' or 'z' to decrease the value. You have to calibrate only once for each load cell.


NOTE : This tutorial only show you on how to interface HX711 with load cell. We did not use the correct calibration factor. You have to set your own calibration factor for your load cell. Check on this video and tutorial to learn on how to set the calibration factor for load cells. Remember that each load cell with different weight ie. load cell 20KG, 60Kg and 100KG have different value of calibration factor. Thus, you will have to set calibration factor for each load cell with different weight.

Step 9: Videos

This video shows how to interface HX711 Balance Module with Load Cell.

Share

Recommendations

  • Tiny Home Contest

    Tiny Home Contest
  • Audio Contest 2018

    Audio Contest 2018
  • Fix It! Contest

    Fix It! Contest

10 Discussions

0
None
Srijal97

Tip 4 weeks ago

Your code was helpful, thanks! One particular thing that I noticed while interfacing an S type load cell was that the load cell only measured either compression/tension at one time based on the connection of the white and green ends to the HX711. For example, when I tried it with White to A- and Green to A+, I was only able to detect compression. I interchanged White to A+ and Green to A- and got tension readings but no compression.

0
None
nkomecharles14

Question 7 weeks ago

hello.. i have difficulties with my loadcell from step 9 .. i dont actually understand how the software part functions... when i run the code i get "0.00g" on the serial monitor and the value does not changes no matter the load i use on the loadcell....

0
None
DharuQ

Question 8 weeks ago on Step 3

Can we handle the fluktasi. Like the number of weigth stop and didn't change everytime.

0
None
zeevon

Question 6 months ago

Your i2c connection diagram also wrong. Your sample program use pin 5,6 for DT & SCK but your diagram show pin 4,5. Wasting time to troubleshoot.

0
None
Budihal

Question 7 months ago on Step 5

Sir I need hx711 adc converter weighing load cell with 8051 ,I need both assembly ,c language code hole program ,because I m beginner so please

1 more answer
0
None
Budihal

Question 7 months ago

I need for this daigram c or assembly language code please any body help me

images (1).jpeg
1 more answer
0
None
abderezak_science

1 year ago

I have a project on the electronic scale with arduino so could you help me to give me the program

0
None
ForssFägerström

1 year ago

Do you have a specific reason for connecting the white and green wire of the load cell the way you did?

In your instructions, the white wire "Output+ (O+), Signal+ (S+)+ or Amplifier+ (A+)" is connected to pin 3 (A-) in J1, which goes to pin 7 (INNA, Ch. A Negative Input) of HX711, and the green wire "Output- (O-), Signal- (S-)+ or Amplifier- (A-)" is connected to pin 4 (A+) in J1, which goes to pin 8 (INPA, Ch. A Positive Input) of HX711.

Also, what do the notations "(S+)+" and "(S-)+" mean? Typo/copy-paste error?