[AllanG]

I have a spare TX module that I'm using for bench testing my solar sensor, so today I uploaded v2.0_b010 software and connected the SHT31 sensor. As I hoped and expected, it appears to work perfectly.

I then decided to compare all three outdoor sensors - HTU21, SHT21 and SHT31.

It certainly wasn't a "scientific" test but all three sensors were tested indoors for just a minute or so each, the whole job taking no longer than 10 minutes, with no temperature and humidity changes in the (closed) room, according to the room thermometer.

The results were quite interesting. Temperature readings were all within one degree. Humidity reading were a little different. The HTU21 showed the greatest variation, the SHT21 next and the HTU31 showing the least variation. I'm now looking forward to seeing some "real life" comparisons!

Here are the readings I took:

SHT31:
Sensor 0 - Temp: 23.96 Hum: 51.49
Sensor 0 - Temp: 23.88 Hum: 50.28
Sensor 0 - Temp: 23.89 Hum: 50.38
Sensor 0 - Temp: 23.92 Hum: 50.62
Sensor 0 - Temp: 23.88 Hum: 50.13
Sensor 0 - Temp: 23.83 Hum: 50.48

SHT21:
Sensor 0 - Temp: 23.36 Hum: 54.87
Sensor 0 - Temp: 23.22 Hum: 55.11
Sensor 0 - Temp: 23.10 Hum: 56.10
Sensor 0 - Temp: 23.13 Hum: 56.33
Sensor 0 - Temp: 23.05 Hum: 55.72
Sensor 0 - Temp: 23.04 Hum: 55.69

HTU21:
Sensor 0 - Temp: 23.59 Hum: 48.38
Sensor 0 - Temp: 23.57 Hum: 49.52
Sensor 0 - Temp: 23.50 Hum: 47.90
Sensor 0 - Temp: 23.50 Hum: 47.57
Sensor 0 - Temp: 23.53 Hum: 48.93
Sensor 0 - Temp: 23.54 Hum: 49.02

Allan.