tatobari / hx711py

HX711 Python Library for Raspberry Pi.
Apache License 2.0
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HX711 Read 0 upon connecting VCC/VDD to power rail but gives output when not connected to Power #45

Open henryminhtran opened 2 years ago

henryminhtran commented 2 years ago

Hi, I'm trying to combine the signal 4 S-beam 5-wire load cells (E+,E-,S+,S-,Sh) into a junction box (Output: E+,E-,S+,S-,Sh), amplify the data through HX711 and into the RPi. Wiring diagrams are as below. After wiring and running the code, the output data keeps being 0 or 1 and sometimes fluctuates to 1000/2000 and dropped back to 0/1 every time I connect VCC and/or VDD to power (3.3V/5V). However, if I disconnect the VCC and VDD, the output read around -833000... In both cases the output doesn't react to the applied weight onto the load cell. IMG_20211123_215657_120 I wasn't sure what was going on. I'm using BCM mode and GPIO pin 5 for DATA and 6 for CLK. So far, I've tried:

  1. switch voltages 3.3V/5V for each at a time AND both at a time for VCC and VDD (output from HX711)
  2. Switch setmode to BOARD
  3. Switch pins 5 and 6 to serial pins( 2 for DATA and 3 for CLK)

According to the datasheet, the S-beam load cells work with voltage up to 10V but the supplier's tech support said that it should still work with 5V, just with less accuracy and requires more tuning. Can you please help me verify what's going on?