UART vs I2C for Atlas Scientific EZO-HUM?H

Hi,

I’m looking to use an Atlas Scientific EZO-HUM to monitor some outdoor greenhouses.

The only issue is it’s around 8-10 metres between the Raspberry Pi, and the actual EZO-HUM sensor. The EZO-HUM comes with a 1.0 meter cable.

Atlas Scientific do make an EZO Sensor Extension cable, which adds another 2.1 metres. However, that page also mentions that I2C is not designed for >= 3.6 metres.

Apparently, if I use UART, it doesn’t have the same distance limitation.

Alternatively, I saw that Sparkfun make a Qwiic differential breakout board, which carries I2C over Ethernet cabling, and would definitely go to 10 metres.

Question 1 - Are there any limitations if I go with UART instead of I2C, in MyCodo? Or any caveats I should be aware of with UART? (i.e. why doesn’t everybody just use UART?).

Question 2 - If I go down the Qwiic differential breakout route, and try to extend it, I’ll need some way of waterproofing where I go from the EZO-HUM cable to the Qwiic board. I was thinking of getting a small IP-rated waterproof box, and then using some cable glands. It is a bit of a clunky approach though.

Does anybody know of an easier, or more sleek way of waterproofing the Qwiic board? The dimensions of the board are:

51mm x 26mm x 18mm (2 “ x 1.02” x 0.71”)

Question 3 - Or how else would you tackle this problem? (Extending the EZO-HUM to 8-10 meters).

Thanks,
Victor