Inaccurate pressure and humidity

Hi there!

My Photon Particle is mounted outside with a Weather Shield and a Battery Shield, itself connected to a 4400mAh lithium-ion battery and a solar panel of 6W. Temperature, pressure, humidity and other parameters are measured and sent every 10 minutes. Temperature measurements are quite accurate. However, pressure and humidity measurements remain inaccurate. For instance, I noticed again this morning that humidity can be above 100 (while it should not exceed 80%) and pressure is systematically below 1000hPa (while it should be around 1015hPa). Any idea?

Nicolas.

Hi Nicolas.

There are two separate sensors for humidity and pressure on the board and for both of them to be giving bad readings would be quite odd. Is there any condensation or rain getting on the board? That could be causing the issue you’re seeing.

You might try bringing the weather shield inside for a few days for any residual moisture to dry out and see if that brings things back to normal.

No condensation on the board, measurements are the same for pressure even inside. Any idea?

Nicolas.

Hi Nicolas.

The only thing I can think of is if condensation had formed in the past and gotten into the sensors, you could be seeing this. Did the humidity reading go back to normal after a few days of being inside?

Is the pressure moving at all or stuck at 1015?

I just checked again: pressure and humidity measurements are still inaccurate, even when used for several weeks inside my house. I had even used the sample code (“SparkFun_Photon_Weather_Shield_Example.ino”) provided with the Photon Weather Shield Library on build.particle.io but the result is the same. Humidity get suck at about 60% and pressure get always stuck below 1000hPa (instead of about 1015hPa). So, what can I do now with such inaccurate measurements?

Best,

Nicolas.

Hi Nicolas.

Can you PM me with your order or invoice number?