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BME280 defective?
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BME280 defective?

by tphoeksma on Mon Nov 26, 2018 7:39 pm

In the end of September this year I bought with help of ModMyPi Ltd a BME280 sensor which is described in the Weather Station Project of the Raspberry Pi Foundation.

After several week with temperatures below zero and hight humidity % I see that the sensor doesn't work fine anymore.
I protected it against rain with help of a finger of a surgeon's glove tightly closed at the top. No rain could come in.

Is it possible that humidity although less and very low temperatures can damage the sensor (parts)?

Is there a better alternative for the BME280 (must be used with Python, so some code would be very helpful.

I hope you can help me.

With regards, Ton Hoeksma
Last edited by tphoeksma on Fri Nov 30, 2018 10:44 am, edited 1 time in total.

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Re: BME280 defective?

by franklin97355 on Mon Nov 26, 2018 9:11 pm

If possible, bring the sensor inside and see if it will recover sanity. What readings are you getting and what do you expect to be getting?

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Re: BME280 defective?

by tphoeksma on Tue Jan 08, 2019 5:27 pm

I have done that but no change.

Is there a sensor that is better capable of dealing with extreme weather conditions?
If yes, which one and is there some help to address it out of a Python program?

Please help!

With regards, Ton

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Re: BME280 defective?

by millercommamatt on Tue Jan 08, 2019 5:46 pm

How extreme conditions do you need a sensor for? What do you want to measure? Are you open to multiple sensors? Are there budget constraints? Are there accuracy constraints?

How extreme were the conditions that affected your sensor? While the BME280 seem quite robust according to its datasheet, I've read of multiple cases where prolonged cold seemed to affect relative humidity readings.

How do you know that the sensor was damaged?


It's possible that being sealed inside the glove exposed the sensor to condensation. The air trapped inside the glove may have fallen below it's dew point if the outside air was cold enough.

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Re: BME280 defective?

by tphoeksma on Tue Jan 08, 2019 6:53 pm

Because of rare readings I knew that something was wrong.

Reading your post, I think you're right that the air in the glove might have condensed and so damage the sensor(s).

I have bought a new one, will pack it in a housing that prevents wetting from rain, but leaving very small hole to let the air get in and out.
Hope that this will give better results.

Thank for responding.

Ton Hoeksma, the Netherlands.

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Re: BME280 defective?

by millercommamatt on Tue Jan 08, 2019 7:24 pm

Just note that for temperature and humidity, the sensor needs to be well ventilated to be accurate.

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Re: BME280 defective?

by tphoeksma on Tue Jan 08, 2019 7:30 pm

Thanks for the advice!

:-)
Ton

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