Qwiic Scale - NAU7802 - Unstable Readings

Sensors Force & Weight
1

Hi,

I have an urgent request on a problem I have been facing for 2 weeks. I read all the spec sheets carefully, looked at the Arduino examples and libraries and various trial and error with no luck.

My setup is as follows: I am using I2C from a zigbee and connect directly into the Qwiic Scale through hole connection (not using the qwiic connectors). I tie 3.3V from the xbee to the AVDD (same voltage i apply to 3V3 throught hole on the qwiic scale board). I reset all registers, did the NAU7802 Analog front calibration already. The readings are jumping around but I know it’s sort of working since when i put the load on it, the overall numbers do go up. When i say jumping around, i mean at zero for example, it would jump from 4000 to 12000, etc. So I don’t think those are noises. When I use the HX711, they are good (jumping within a relative range) with the raw numbers.

Is there something I am missing? I am guessing it must be…

Thanks!

2

Sadly we can’t support the NAU7802 on your Zigbee module. Have you tried connecting it to an Arduino and using our example code?

One other thing to check is your load cell wires. I recommend tinning them before inserting into the spring terminals. Bare wires can have oxides on them that create a small amount of resistance and that can wreak havoc on your readings. Tinning the wires will clean any oxides of and give the spring terminals a nice soft area to make contact with.