Arduino Hx711 Weight Scale Interface 1 0 Software

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The sensorsare quite posibly configured as in Fig1 in the data sheett If so there should be +5 and 0V across two points and weight signal between two others. Use a DMM to Check for 5V (probably 5V = E+). So find two leads with Vdd (5V or similar). Other two probably at Vdd/2 abov ground. Connect meter on LOW V range between other two and see if reading varies with weight change. Report back.

As jwpat7 says - you may need to repower sensors off HX711 supply to get correct readings. HX711 looks nice.–May 18 '15 at 2:47. I know where is GND and VDD on HX711 module, and where goes the signal wires(A-,A+,B-,B+).

That is clear. I dont know which colors of wires from sensors is GND VDD and Signal. I will do this. I will put back the power on the scale (3v from battery) and I will try to measure wires to determine what is what (i will put some load on the scale).

I have a multimer so i will try to determine which wires are signal, and which wires are GND and VDD. I will report back. Tnx Russell.–May 18 '15 at 7:17. Your four half bridge load cell sensors can connect into a full wheatstone bridge as inIf your sensors are like this 50kg load cell from SparkFun's or Ebay's they might have a compression and tension gage both on the top surface. The Ebay site has a diagram like.

Which indicates a positive strain gauge on the red-white, and a negative strain on the red-black. (note that the coloring order in this diagram does not match the coloring order in this picture. I have a similar gauge with blue-red-black colors, and the positive strain gauge is the right pair, negative on the left.) The gauged surface on the center bar between the face-to-face coupled 'E's in the sensor should act like a parallel bar and has portions under compression and under tension, rather than purely under tension. In cross-section, the gauged bar in the center is sort of the cross-piece in a Z-shaped spring. In this case, the strains oppose each other, and, if manufactured well, the reduction of resistance in the negative strain portion will offset the increase in resistance in the positive strain portion and the total white-black resistance should be constant. The HX711 provides power to a bridge and amplifies the bridge's differential voltage.

The scale's original circuit board (which drives an LCD readout) also provides power to a bridge. You are unlikely to get any useful readings while both circuits are applying power to the bridge.(You could cut the existing wires and attach connectors to allow changing back and forth between the original board and your Arduino circuit.). Some scales like the one shown use a 9 V battery to run the electronics. That voltage, if used, is likely to be incompatible with connecting an Arduino (typically powered by 3.3 V or 5 V) or an HX711 (powered with VDD in the range 2.7 V to 5.5 V) at the same time as the original board. Text mainly from my comments with some additions - with image added.The sensors are quite possibly configured as in Fig1 in the data sheet.If so there should be +5 and 0V across two points, and weight signal between two others.Use a DMM to Check for Vdd (probably 5V if pV battery, = 3V with Lithium battery). Find two leads to bridge with = Vdd on.

Other two probably at Vdd/2 above ground. It is likely there are 4 wire effectively so each of the red wires on one side may be conncted tpo one on the other side - an Ohm-meter will tell you. Connect meter on LOW V range between other two and see if reading varies with weight change. Report back.As jwpat7 says - you may need to repower sensors off HX711 supply to get correct readings.HX711 looks nice. Under $1/module in modest volume on Alibaba and under $US/0.50 / IC in hundreds.What Fig1? I know where is GND and VDD on HX711 module, and where goes the signal wires(A-,A+,B-,B+).

That is clear. I dont know which colors of wires from sensors is GND VDD and Signal. I will do this. I will put back the power on the scale (3v from battery) and I will try to measure wires to determine what is what (i will put some load on the scale). I have a multimer so i will try to determine which wires are signal, and which wires are GND and VDD.

I will report back. –See fig of for larger view of this image. The sensor you have in your scale are a simple voltage dividers. Each consist of one resistor and one extensiometer, both connected in series. One wire (E+) is VDD another (E-) is GND and the third is divider output(S).

You can not directly use it with HX711 which needs a bridge sensors not just dividers. You can try to set a 1/2vdd on S- and connect the signal from the sensor to S+. In case you get a negative weight, simply swap these connections. Your assumption that your scale uses full bridge, because it has four sensors, is completly wrong.

You can read the signals from the scale sensors using analog inputs in you arduino (without HX711) but you should amplify it before to get reasonable resolution. Good luck!Greg.

This Instructable describes how to make a weighing scale using readily available off the shelf parts.Materials needed:. Arduino - (this design uses a standard Arduino Uno, other Arduino versions or clones should work also). HX711 on breakout board - This microchip is specially made for amplifying the signals from load cells and reporting them to another mircocontroller. The load cells plug into this board, and this board tells the Arduino what the load cells measure. 50kg load cells (x4) - Load cells are specially shaped metal parts that have strain gauges glue to them. The strain gauges are resistors that change their resitance when they are bent. When the metal part bends, the resistance of the load cell changes (the HX711 measures this small change in resistance accurately).

You can buy the load cells and HX711 as a kit here: If you do purchase the kit please leave a review! It is really helpful for future buyers. Sturdy flat mounting surface - a stiff piece of hardwood or metal is ideal.

Wires in various colors for connecting all the parts. Power supply for Arduino. Hello, I am working on a beehive scale using these sensors and setup. I had the same problem and the reason was that the HX711 library updated during March in a way that is not compatible with old projects anymore. Remove all versions of HX711 library that you installed, delete them from the local folder and install the previous version of the library. The scripts of this article was written based on the previous version.

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Check here, For me everything works. The calibration script is what i needed.