![\"Arduino](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/04\/Arduino-load-cell-HX711-amplifier.jpg?resize=1200%2C675&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\nTable of Contents<\/strong><\/p>\n\n\n\n In this tutorial, we’ll cover the following topics:<\/p>\n\n\n\n A load cell converts a force into an electrical signal that can be measured. The electrical signal changes proportionally to the force applied. There are different types of load cells: strain gauges, pneumatic, and hydraulic. In this tutorial, we’ll cover strain gauge load cells.<\/p>\n\n\n Strain gauge load cells are composed of a metal bar with attached strain gauges (under the white glue in the picture above). A strain gauge is an electrical sensor that measures force or strain on an object. The resistance of the strain gauges varies when an external force is applied to an object, which results in a deformation of the object’s shape (in this case, the metal bar). The strain gauge resistance is proportional to the load applied, which allows us to calculate the weight of objects.<\/p>\n\n\n\n Usually, load cells have four strain gauges hooked up in a Wheatstone bridge (as shown below) that allow us to get accurate resistance measurements. For a more detailed explanation of how strain gauges work, read this article<\/a>.<\/p>\n\n\n The wires coming from the load cell usually have the following colors:<\/p>\n\n\n\n Applications<\/strong><\/p>\n\n\n\n Strain gauge load cells can be used in a wide variety of applications. For example:<\/p>\n\n\n\n Because the changes in strain when weighting objects are so small, we need an amplifier. The load cell we’re using is usually sold together with an HX711 amplifier. So, that’s the amplifier we’ll use.<\/p>\n\n\n\n The HX711 amplifier is a breakout board that allows you to easily read load cells to measure weight. You wire the load cell wires on one side, and the microcontroller on the other side. The HX711 communicates with the microcontroller using two-wire interface (Clock and Data).<\/p>\n\n\n You need to solder header pins on the GND, DT, SCK, and VCC pins to connect to the Arduino. I soldered the load cell wires directly to the E+, E-, A-, and A+ pins. The load cell wires were very thin and fragile, be careful when soldering to not damage the wires.<\/p>\n\n\n <\/p>\n\n\n\n For more information about the HX711 amplifier, you can consult the HX711 datasheet<\/a>.<\/p>\n\n\n\n Our load cell kit came with two acrylic plates and some screws to set up the load cell as a scale. You can use wood plates or 3D-print your own plates.<\/p>\n\n\n You should attach the plates to the load cell in a way that creates a strain between the opposite ends of the metal bar. The bottom plate holds the load cell, and the upper plate is where you place the objects.<\/p>\n\n\n The following figure shows what my load cell with the acrylic plates looks like.<\/p>\n\n\n You can check the load cell with the HX711 on Maker Advisor to find the best price (with or without acrylic plates included). There are load cells with different measurement ranges. The most common maximum weights are 1kg, 5kg, 10kg, and 20kg.<\/p>\n\n\n You can use the preceding links or go directly to MakerAdvisor.com\/tools<\/a> to find all the parts for your projects at the best price!<\/p> The HX711 amplifier communicates via two-wire interface. You can connect it to any digital pins of your Arduino board. We’re connecting the data pin (DT) to Pin 2<\/span> and the clock pin (CLK) to Pin 3<\/span>.<\/p>\n\n\n\n Follow the next table or schematic diagram to wire the load cell to the Arduino board.<\/p>\n\n\n\n\n
Introducing Load Cells<\/h2>\n\n\n\n
![\"load](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/03\/load-cell.jpg?resize=750%2C422&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n![\"load](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/03\/load-cell-setup-scale-wheatstone-brifge-01.png?resize=750%2C500&quality=100&strip=all&ssl=1\")
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HX711 Amplifier<\/h2>\n\n\n\n
![\"HX711](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/03\/hx711-amplifier.jpg?resize=750%2C450&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n![\"HX711](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/03\/hx711-amplifier-soldered.jpg?resize=750%2C422&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\nSetting Up the Load Cell<\/h2>\n\n\n\n
![\"load](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/03\/Load-cell-hx711-amplifier-package.jpg?resize=750%2C422&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n![\"load](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/03\/load-cell-setup-scale.png?resize=750%2C332&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n![\"load](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/03\/load-cell-scale-arduino.jpg?resize=750%2C422&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\nWhere to Buy Load Cell with HX711?<\/h2>\n\n\n\n
![\"Load](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/03\/load-cell-hx711-amplifier-product.png?resize=263%2C186&quality=100&strip=all&ssl=1\")
<\/a><\/figure><\/div>\n\n\n\n
![](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/10\/header-200.png?w=1200&quality=100&strip=all&ssl=1\")
<\/a><\/p>\n\n\n\nWiring Load Cell and HX711 Amplifier to the Arduino<\/h2>\n\n\n\n
![\"Arduino](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/04\/Arduino-load-cell-diagram_bb.png?resize=1200%2C731&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n![\"Install](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/03\/Install-HX711-Bogdan-Library-Arduino-IDE.png?resize=786%2C443&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n![\"Calibrate](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/04\/calibrate-load-cell-arduino-serial-monitor.png?resize=683%2C415&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n![\"Load](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/04\/Arduino-digital-scale-demonstration.png?resize=684%2C495&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n![\"Arduino](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/04\/arduino-digital-scale.jpg?resize=750%2C422&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n![\"ESP8266](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/04\/Arduino-digital-scale-schematic-diagram.png?resize=1200%2C1132&quality=100&strip=all&ssl=1\")
<\/a><\/figure><\/div>\n\n\n![\"Pushbutton](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2022\/03\/pushbutton-library-polulu-arduino-ide.png?resize=786%2C443&quality=100&strip=all&ssl=1\")
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