Load Sensor HX711 ESPHome ESP32s values jumping around

[liminal (Shane)]

Hey all,

Try to make this as succinct as posable. After first putting this together I was getting wildly fluctuating readings. The below wiring specified 5v and after changing to that, I’m now getting

[12:37:59][D][hx711:031]: 'Bed Sensor': Got value 0
[12:37:59][D][sensor:121]: 'Bed Sensor': Sending state 0.00000  with 0 decimals of accuracy
[12:38:09][D][hx711:031]: 'Bed Sensor': Got value 0
[12:38:09][D][sensor:121]: 'Bed Sensor': Sending state 0.00000  with 0 decimals of accuracy
[12:38:19][D][hx711:031]: 'Bed Sensor': Got value 0
[12:38:19][D][sensor:121]: 'Bed Sensor': Sending state 0.00000  with 0 decimals of accuracy
[12:38:29][W][hx711:037]: HX711 is not ready for new measurements yet!
[12:38:39][D][hx711:031]: 'Bed Sensor': Got value 0
[12:38:39][D][sensor:121]: 'Bed Sensor': Sending state 0.00000  with 0 decimals of accuracy
[12:38:49][D][hx711:031]: 'Bed Sensor': Got value 0
[12:38:49][D][sensor:121]: 'Bed Sensor': Sending state 0.00000  with 0 decimals of accuracy
[12:38:59][D][hx711:031]: 'Bed Sensor': Got value -8
[12:38:59][D][sensor:121]: 'Bed Sensor': Sending state -8.00000  with 0 decimals of accuracy
[12:39:09][W][hx711:037]: HX711 is not ready for new measurements yet!
[12:39:19][W][hx711:037]: HX711 is not ready for new measurements yet!
[12:39:29][D][hx711:031]: 'Bed Sensor': Got value 0
[12:39:29][D][sensor:121]: 'Bed Sensor': Sending state 0.00000  with 0 decimals of accuracy
[12:39:39][D][hx711:031]: 'Bed Sensor': Got value 0
[12:39:39][D][sensor:121]: 'Bed Sensor': Sending state 0.00000  with 0 decimals of accuracy
[12:39:49][W][hx711:037]: HX711 is not ready for new measurements yet!
[12:39:59][D][hx711:031]: 'Bed Sensor': Got value 0
[12:39:59][D][sensor:121]: 'Bed Sensor': Sending state 0.00000  with 0 decimals of accuracy

ESP32s

XC3800-dataSheetMain.pdf

ESPHome

sensor:
  - platform: hx711
    name: "Bed Sensor"
    dout_pin: GPIO21
    clk_pin: GPIO22
    gain: 128
    update_interval: 10s

Green HX711 amp

I have a bed currently on the load cells with the idea that I would set that as 0KG and use my weight as registered from a scale to calibrate.

Bed sensor before and after switching 3.3 to 5v

Did I fry the amp moving it to 5v? or was it just never working?

Thanks all

EDIT: So the HX711 have an operating voltage from 2.65 to 5.5v so I cant have fried it right.

[tom_l]

@liminal

the HX711 have an operating voltage from 2.65 to 5.5v so I cant have fried it right.

You may have damaged the ESP data and clock inputs though. They only operate on 3.3V logic.

[liminal (Shane)]

Hey mate,

Hope you’re well!

Ok, so I got out another ESP32 and as I was plunging it in released I had the dout_pin clk_pin round the wrong way. sigh lol

Fixed that and I’m now getting a consistent reading, the same, regardless of which ESP32 I have plugged in or weight applied.

[15:23:53][D][hx711:031]: 'Bed Sensor': Got value 8388607
[15:23:53][D][sensor:121]: 'Bed Sensor': Sending state 8388607.00000  with 0 decimals of accuracy
[15:24:03][D][hx711:031]: 'Bed Sensor': Got value 8388607
[15:24:03][D][sensor:121]: 'Bed Sensor': Sending state 8388607.00000  with 0 decimals of accuracy
[15:24:13][D][hx711:031]: 'Bed Sensor': Got value 8388607

Could it be the wiring. I notice that The Hook Up has one way of wiring the bridge, this guy has another way

HX711 with a Four Wire Load Cell and Arduino | Step by Step Guide.

Are they all the same way to skin a cat, or some are better then others. I don’t know much about circuits sadly.

EDIT: If I change the wiring to the Hook Up guide, Im still getting the same 8388607 value.

Should I use try different pins?

[liminal (Shane)]

Ok, I think I’ve almost got to the bottom of this. I got sent a dodgy version with swapped wiring colours on the load cells.

Basically white and black are swapped around and ive soldered them like this.

So looking at (1) in this diagram, is there a pin combination that would accommodate the white and black wires being swapped around?

Thanks all

[Haze]

Just made a 3D printed platform for my bed sensor.
If anyone is interested, I will post on here. Here are some pics.

Bottom plate and 4 covers for each of the corners.

Sensor designs taken from here: and embedded in the platform.
Having a few clips printed tomorrow I hope that will hold the wires down in the tracks.