I recently purchased a fully assembled outdoor monitor and after a few days I’ve noticed a consistent error in the humidity sensor readings. It appears to be both an offset and scale error. Is it possible to calibrate this sensor?
Here’s a comparison with my Tempest Weather station currently mounted only a few meters away.
We had a calibration factor for the outdoor unit in place and then it turned out that different batches from Plantower behave differently.
We are currently checking how we can identify these different batches and are also implementing the possibility to define an offset and slope.
Thanks for the update, please let me know if there’s anything I could help with.
Here’s an updated plot for the ~week I’ve had the outdoor monitor.
Here you see the correction analysis we did. Now that we found out that different batches of the PMS5003T behave differently, we need to implement a per sensor calibration.
I have noticed that your O-1PST has reported 0% humidity three times within 72 hours. Do you observe these readings frequently? Are the corresponding temperature or PM readings unexpectedly low as well? I am curious.
I’m not sure, I was assuming it had something to do with home assistant rather than the airgradient itself, but I haven’t looked into it yet.
Here’s humidity (plotted in home assistant) from the past week followed by humidity from the airgradient dashboard.
Temperature for the outdoor monitor in home assistant is even worse going to -1000 when it drops out.
Other than those datapoints it looks pretty reasonable though.
These outliers are currently being fixed. See:
We need to check if that would capture humidity 0 as well.
Actually on the chart the humidity readings look more like -1 which already indicates an error. So it should be ok.
