BSEC 1.4.8 and iaq-siaq/accuracy relation

[longo92]

Hi,

i'm developing an air qualiry logger using BME680 and BSEC 1.4.8.0 lite library.

Every 5 minutes the logger collects data from sensor and sends them to a server.

The sensor is configured to work in ULP (with generic_18v_300s_4d configuration) and has iaq/s-iaq/co2eq/breath-voc/gas percentage enabled.

After some days i get following data:

The strange thing is that i get accuracy 3 and reasonable data on 01.10.2022-10:06., after i get samples with accuracy 2 (medium accuracy: auto-trimming ongoing) and "strange" values (at least to me!):

• Tiemstamp: 01.10.2022 10:11
• iaq = 25.0
• s-iaq=25.0
• co2-eq: 500 ppm
• breath-voc: 0.5ppm 
• gas-perc: 0.0%

Is this correct? Is normal go back to accuracy 2 for some time with those values?

Thanks,

Alessandro

 

[BSTRobin]

Hi longo92,

When you use these values, it is recommended that you use values with an accuracy of 3.