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By keebler411
#204371
I followed the industrial IoT tutorial and have a scale working with the NAU7802 chip. I used a combinator board to connect the for load sensors. However, I can't replicate the setup to another 4 sensors. I've soldered up 2 sets of sensors and get the same results:

1) If I leave A+/A- connections the same as with the scale that works I get a really large number (shy of 24 bit max value) and it doesn't change much unless a huge force is applied

2) If I reverse A+/A- I get a no load reading in the same range as the working scale

3) If I now apply gradual pressure with say my foot I see the reading decrease until it underflows and I get a large number like before

4) Within the range of no load to just before underflow I can calibrate the scale and get a slope that is about the same magnitude as the working scale (good), but obviously negative because I reversed the connections.

I've carefully checked the connections and had other people check them too. Any ideas?