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bkpsu / NodeMCU-Home-Automation-Sensor

Readme/Diagram for the "Kube" NodeMCU/DHT22 based MQTT temp/humidity home automation multi-sensor with local OLED display)
https://www.thingiverse.com/thing:2539897
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Add pressure sensor support #3

Closed bkpsu closed 6 years ago

bkpsu commented 6 years ago

Looking at MPXV7002 differential pressure sensor, for possible use as a static pressure monitor for HVAC systems. Kube would monitor/report static pressure (and possibly calculate CFM) to HA system, for coordination with automated (or manual) register control, to avoid over pressurizing the HVAC system.

MPXV7002 is an analog (5V) sensor, so work needs to be done to test reading the analog input into the ESP8266's ADC input and make sure resolution/readings make sense.

bkpsu commented 6 years ago

Latest commit adds software support for the MPXV7002 sensor, but initial testing with the sensor (attached in series with a 180Kohm resistor to drop the 0-5V to 0-1V ADC input) shows bad fluctuation of input even at static pressure (both ports on the sensor tied together). Need to look at using external, lower-range sensor with I2C input most likely, or figure out what's causing the erroneous readings (voltage supply or bad sensor?)