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metriful / sensor

Sensor by Metriful | Indoor environment monitoring | Documentation and code samples
https://www.sensor.metriful.com
MIT License
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Shinyei PPD42 - ppL unit of measure #19

Closed MynameisComo closed 3 years ago

MynameisComo commented 3 years ago

Hi, I would like to understand which kind of output value is shown by your code, what means ppL unit of measure? As per producer docs they refer to pcs/0.01cf unit of measure, and the sample value is get out every 30 seconds (if I understud well). Could you please explain ppL unit of measure and core logic regarding this acquiring? Thanks in advance. Marco

metriful commented 3 years ago

Hi,

ppL means "particles per litre"

pcs/0.01cf means "particles per 0.01 cubic feet"

0.01 cf is 0.283 litre, so we converted to metric.

The 30 seconds is the manufacturer's recommended minimum signal averaging time.