This is the water flow sensor:
This graph shows the water flow into my house over a 32 hour period: The big spike around 7AM-8AM is from our sprinkler system.
The flow meter is in the water line coming from the city, into my house, just after the main water shutoff valve. This means that all the water my household uses is measured. The sensor has a paddlewheel in the water flow that rotates when water is flowing. When the paddlewheel spins, the sensor emits pulses. Those pulses are counted by my ARM based Linux system. Every minute software running on the ARM Linux system emits a line of data that has the date and time as well as the number of pulses. The software converts pulses-per-minute to gallons-per-minute (about 700 pulses represents one gallon).
For people who want to see the raw data, here it is: --- Raw Water Flow Data
Back to graphs (top level page)
Last updated January 28, 2009. For more information, contact robert-pool@bedichek.org