Comparison of two BME280 sensors
Two BME280 sensors (purchased at the same time but otherwise unmatched) were co-located and monitored from two Raspberry Pi cards (RasPi-3 and RasPi-5). The graphical comparison after approximately 42 hours running is shown below:
The MRTG recorded "day" values were:
| RasPi-3 | RasPi-5 | Specified accuracy |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Maximum | Average | Current | Maximum | Average | Current | |||||
| Temperature | 24.9 | 23.3 | 24.0 | 25.4 | 23.6 | 24.3 | ± 1°C | |||
| Pressure | 1019.6 | 1015.4 | 1019.5 | 1019.7 | 1015.5 | 1019.6 | ± 1 hPa | |||
| Humidity | 45.7 | 43.5 | 40.8 | 44.8 | 42.8 | 40.2 | ± 3% |
So the difference between the two samples in temperature ranged from 0.3 to 0.5 °C (spec. ± 1°C), in pressure a consistent 0.1°C (spec: ± 1 hPa), and in humidity 0.6 to 0.9% (spec: ± 3%). This gives you an idea of what might be achievable.
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