BMP180 outdoor enclosure & wire lengths?

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uxhamby
 
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BMP180 outdoor enclosure & wire lengths?

Post by uxhamby »

Any recommendations for an outdoor enclosure for the BMP180 board?

Also, what sort of I2C cable lengths are practical?

Thanks,

Brian H.

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adafruit_support_bill
 
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Re: BMP180 outdoor enclosure & wire lengths?

Post by adafruit_support_bill »

These are pretty small, so most any small waterproof container (e.g. a pill-bottle) would work. Just be sure not to seal it completely. You need to allow the internal & external pressures to equalize in order to get a valid barometer reading.

i2c is designed for short distances. But it can be extended if you keep the line capacitance low and/or slow down the i2c clock. There are also buffer chips that can be used to extend it further: http://www.esacademy.com/en/library/tec ... c-faq.html

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egutting
 
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Re: BMP180 outdoor enclosure & wire lengths?

Post by egutting »

From what I've read, the barometer should be the same inside a house as it is outside. http://scienceline.ucsb.edu/getkey.php?key=907 (Just an FYI if you were planning on using it for weather purposes)

If you're planning on using the temp part of the sensor outside, you have to make sure that air can cross the sensor and that the container isn't affected by the sun.

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