HX711 Load Cell Amplifier, Weighing Scale Design In this arduino tutorial of HX711 Load Cell amplifier interface. We are interfacing 40Kg load cell to the arduino using HX711 Load cell amplifier module. HX711 is a precision 24-bit analogto-digital converter (ADC) designed for weigh scales and industrial control applications to interface directly with a bridge sensor. The input multiplexer selects either Channel A or B differential input to the low-noise programmable gain amplifier (PGA).

The load cell I have has a sensitivity of 1.966 mV/V at 50kg. This is then amplified to 0.2555 V/V. This is then 0.511 of the Hx711 half scale output of 0.5 V/V. The digital output is therefore 0.511 x 800000 in hexadecimal. This will be 4286579 in decimal for 50 kg. The sensitivity is then 85731 per kg. How to Build Arduino Weighing Scales: At the Restart Project in London we. Hence I will concentrate on the electronics, the software and the underlying. Step 1: Choosing Your Load Cells. To use the HX711 module on the breadboard, solder a 4-wide pinstrip to the interface pins (GND, DT, SCK, VCC) of the HX711.

Channel A can be programmed with a gain of 128 or 64, corresponding to a full-scale differential input voltage of ±20mV or ±40mV respectively, when a 5V supply is connected to AVDD analog power supply pin. Channel B has a fixed gain of 32. Onchip power supply regulator eliminates the need for an external supply regulator to provide analog power for the ADC and the sensor. Ikonki dlya klana. Clock input is flexible.

It can be from an external clock source, a crystal, or the on-chip oscillator that does not require any external component. On-chip poweron-reset circuitry simplifies digital interface initialization. There is no programming needed for the internal registers. All controls to the HX711 are through the pins. Load Cell Connection diagram and its Pinout HX711 Module HX711 Module Most Load cell have four wires red, black, green and white.

On HX711 board you will find E+, E-, A+, A- and B+, B- connections. Connect load cell Red wire to E+ Black wire to E- Green wire to A- White wire to A+ Load Cell Load cell comes in various weights depending on your application select the load cell weight specification, In this tutorial I have used 40Kg, Precision Grade C2 load cell.

Load cell also have precision type. Precision classes explained: Which load cell for which application? Load cells are ranked, according to their overall performance capabilities, into differing accuracy classes or grades. A specific accuracy grade specifies an error envelope for certain parameters, such as linearity, hysteresis, temperature effects, creep, etc.

In practice, certain system accuracy parameters depend considerably on the application of use, physical load introduction to the transducer and disturbing factors such as Zener barriers and surge protection devices. Load Cell Classification Load cells with different accuracy classes are required depending on the application. The chart provides an overview of typical applications, ranging from the lowest to the highest accuracy class. Load cells with relatively low accuracy classified D1 to C2 are sufficient for simple building materials scales used to weigh sand, cement or water. Adding the right proportion of additives to building materials is essential. For this purpose, special building materials scales using accuracy class C3 load cells are available for mixing additives such as ash or sand.