HX711 can't calibrate in a good way

[kellyq]

Hello there

I have problem with calibrating hx711. I made pcb with 2 separate modules to work with load cell. They are indeendent only power is the same. Module on right side works perfect, auto calibration works as i except. Left module not calibrating properly. Calibration factor is much diffrent that it should be. When I push with finger rght lod cell, weight increse pretty good as I except. Left module after touching increse weight to about 497-500g, what is weight of sample used for calibration. More pushing load cell get decrease weight on lcd. This is something what I can't understend.

Both module have same software, schematic, vary only a bit pcb routing.
I think that is problem but can't understand whatcauses this. Can anybody help?

hx711 calibration error

[Railroader]

Check solderings, remake any looking different.

[PaulRB]

Have you tried swapping the load cells?

[kellyq]

Wow, I swapped load cells and happens something interesting, must do more tests.