A personal project to create a pressure-based fan speed controller. The idea is that, in a well airsealed house, we can use a pressure sensor (probably a sensirion sdp810-125pa) to measure the differential pressure between inside and outside, and use that to ramp a makeup air fan up and down, to try to zero out the pressure differential.
Since most controllable HVAC fans use 0-10v DC logic for the control signal, I decided to use a controllable potentiometer (Adafruit DS3502 breakout board) as a simple voltage divider. An alternative design could use a PWM signal, but that would still need to be amplified to the 0-10v signal range of the fan.
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