AQM II - "cal" connector - Printable Version

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AQM II - "cal" connector - Barrow4491 - 30-05-2019

Hi,
Back from holidays and building my new AQM; l notice on the pcb a connector labeled “cal”, could you please explain the use of this connector.
Is there a schematic available?
Regards
Jim

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RE: AQM II - "cal" connector - werk_ag - 31-05-2019

Hello Jim,

The connector labelled "cal" is connected to HD pin on the MH-Z19B sensor, used for a manual ZERO point calibration. Usually doing a ZERO point calibration isn't necessary.
For more info refer to MH-Z19B datasheet:

https://www.winsen-sensor.com/d/files/infrared-gas-sensor/mh-z19b-co2-ver1_0.pdf

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