HX711 and Raspberry Pi3

Community Projects
1

Hi,

Can somebody help me with HX711 loadcell sensor and Raspberry Pi3?

I need to get those communicating with together. What I need to do? I´m rookie with these so please give me quite simple quide what I need to do.

I already connected HX711 to the tension load sensor, but now I need to know to which pins I need to connect HX711 and Raspberry Pi?

In Rasperry I have already installed raspian Jessie.

And also where I can find correct code to the that HX711 sensor and how I can install/add that code to the Raspberry Pi

I hope that above are all question where I need answer this moment, but if there are something else what I need to know please tell me.

Regards.

2

Hi,

Now I get that Project that far that I get below information from tension load sensor. It is same how much I put load to the sensor results are the same:

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 n: 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 n: 0

SNIP

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 n: 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 n: 0

No data to consider

Please can somebody help me?

3

Please can somebody help me?

With the information that you've given us so far? No.

Assuming that you want help, rather than are just asking if it’s possible for people to help you:

It looks like you’re using https://github.com/ggurov/hx711 Please confirm this.

Assuming that this is the software that you’re using,

Is your clock pin 31?

Is your data pin 30?

If you can’t change which pins you’re using, are you comfortable changing your pin constants in the software and recompiling?

Are your supplying at least 2.7V but no more than 5V to the pin marked VCC on the HX711?

Is the pin marked GND on the HX711 sharing the same ground as your power supply?

Most importantly of all, the one thing that we can not and will not be able to provide assistance without, and quite possibly the reason why you’ve been ignored until now: Would you please provide a circuit diagram or a picture of your project?

4

what instructions are you following:

  • I tried to find instructions how I can get my Project combination working

what equipment have you got:

  • I have below equipment:

  • Raspberry Pi 3

  • SparkFun Load Cell Amplifier - HX711

  • Laumas FUN Load cells for wire rope measuring sensor

what have you plugged where

  • I have made below connections:

  • Load cell plugged to the Sparkfun load cell amplifier HX711

  • Load cell amplifier HX711plugged to the Raspberry Pi

  • HX711 VCC ↔ Raspberry Pi pin 2

  • HX711 DAT ↔ Raspberry Pi pin 16

  • HX711 CLK ↔ Raspberry Pi pin 18

  • HX711 GND ↔ Raspberry Pi pin 20

what have you done

  • Already installed Jessie to the Raspberry Pi and also move HX711 code to the raspberry like below link:

http://hivetool.org/w/index.php?title=I … X711_to_Pi

what appears not to work

  • I dont any other results than 0 0 0 0 0 0 → although put any kind load to the load cell.

Hope you get enough information.

5

Need more information:

Please paste the constant definitions for your pins from the file hx711.c

They’re lines that start with “#define” and should look like the following:

#define CLOCK_PIN	31
#define DATA_PIN	 30

(Also, for anyone else following the conversation, the munged link that the user provided, obviously from another forum post where they’re getting help, is http://hivetool.org/w/index.php?title=I … X711_to_Pi )

6

I use below:

#define CLOCK_PIN 24

#define DATA_PIN 23

7

Assuming that this is the load cell family in question:

http://www.laumas.com/en/product/fun-lo … wire-rope/

Looking at the datasheet, your load cell’s wiring is different from the normal wiring colors for load cells.

-Signal is white.

+Signal is green.

Both the Sparkfun hookup guide and the hivetool.org tutorial that you linked to above expect +Signal to be white and -Signal to be green. Try swapping those.

8

I made change white and green wire, but now I dont get any result.

Even 0 0 0 0 0 0 0 0 0 not visibled.

9

how i need start that hx711 program? Should I use double click method with that hx711 file or should I use terminal Window and use command sudo ./hx711? or what?

10

I rebooted Raspberry and now I can again that same below result:

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 n: 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 n: 0

SNIP

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 n: 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 n: 0

No data to consider

11

My connection is below:

Laumas Load cell sensor “+ EXCITATION - red” connected to HX711 “Red (Excitation+ or VCC)”

Laumas Load cell sensor “- EXCITATION - black” connected to HX711 “Black (Excitation- or GND)”

Laumas Load cell sensor “+ SIGNAL - green” connected to HX711 “White (Amplifier+, Signal+, or Output+)”

Laumas Load cell sensor “- SIGNAL - white” connected to HX711 “Green (Amplifier-, Signal-, or Output-)”

HX711 “VCC” connected to Raspberry Pi pin 2

HX711 “DAT” connected to Raspberry Pi pin 16

HX711 “CLK” connected to Raspberry Pi pin 18

HX711 “GND” connected to Raspberry Pi pin 20

  • Copied from https://github.com/ggurov/hx711 website all HX711 files to the SD Card

  • Added SD Card to Raspberry Pi

  • Created new folder “hx711” to the Raspberry Pi root

  • Copied HX711 files to the Raspberry Pi hx711 folder

  • Changed #define CLOCK_PIN to 24 and #define DATA_PIN to 23

  • In terminal Windows gone to hx711 folder

  • run gcc -o HX711 HX711.c gb_common.o

  • run sudo ./hx711

12

Not 100% sure on this being an absolute requirement, but I work with a lot of instrumentation (load cells, analog inputs on industrial systems) and I ALWAYS use an amplifier to boost the millivolt signals from the load cell to something useable on the device receiving the signal. It’s not even an option.

have a look at this thread.

also, Google “Load Cell Raspberry Pi” for more threads where people are trying to do what you are also trying…

13

@Danv:

The HX711 is an amplifier (also an analog-to-digital converter). See https://www.sparkfun.com/products/13230

The load cell is one of these: http://www.laumas.com/en/product/fun-lo … wire-rope/

14

@ghedipunk and @Danv

Those are correct parts what I try to get communicate with together.

Is that so that this combination is not possible?

15

edit: Bad advice. DOn’t do what I originally suggested here.

16

From everything that I can tell, it should work as it’s set up.

The next step that I’d take is to get a multimeter out and make sure that none of the circuits are damaged.

17

I already changed HX711 and raspberry Pi to the other if those are damaged but same result. Only what i dont have yet change is that load cell sensor. Is there some possible that Pi3 is not working to this combination and I should use Pi2?

18

Now I get data from load cell sensor, but I dont know where Raspberry write it. Raspberry Pi processor running about 25% and when I measured from HX711 pins singal+ and signal- I get little voltages (approx from 0.00 to 2.3 mV) depends how tight I can get load cell screws.

Can somebody tell me where I find load cell datas?