The square and circular sunked surfaces are there to accomodate the bumps present on the sensus 620’s front plate, so that the holder can stick perfectly. The sunked surfaces are there to accomodate the few solder pins that are present on the bottom of the TCRT5000 module PCB Below are two views of the 3D model I created using Sketchup Make: Better mounting plateĮven though things worked just fine with the mounting plate described above, I used this as an opportunity to experiment with online 3D printing. The two plastic pegs ensure that the device does not move during measurements, yet it can be easily removed if needed. I used black tape and a small opening window, to minimize the influence of external light on the measure.įinally, here is a view of the device mounted on the water meter: Here is a view of the top:Īnd here is a view of the bottom, with the small opening for the IR LED & photodiode. To ensure that the sensor would be properly located right above the border of counting wheel, I cut a plastic mount plate fitting the original meter shape and plastic pegs positions, then taped the sensor on top of it. In my case however, it turned out to be difficult to find an appropriate threshold that would correctly detect the wheel rotations, so I ended up using the analog output (A0) and implementing my own filtering/threshold detection logic in the arduino Installation Quick & dirty mounting plate D0 ouput changes state when the threshold is crossed. Note: the D0 output is the digital output of the voltage comparator, which threshold can be set with the onboard potentiometer. So the interface if quite simple: supply VCC (5V) and GND, and the analog value of how much light is getting received on the photodiode is available on pin A0: The module I bought integrates the TCRT5000 along with an integrated voltage comparator (that I will not use) and a couple of LEDs and resistors. Light emitter & sensor: I chose to use a TCRT5000 module (less than 4$ at DealExtreme), it includes an IR LED with associated IR photodiode. A battery pack could probably do the trick too, but since this device will be located in my garage, I did not want to bother changing batteries every now and then, nor did I want to optimize the setup for lowest possible power consumption (which would require a smarter arduino code, waking up from sleep upon an external event when the watermeter activates) For the final setup, I used a separate 5V power supply.
Error codes for sensus water meter pro#
The two round plastic pegs will be useful for the mechanical alignment of the sensor on top of the wheel (more on this later) Assembling the sensor systemĪrduino board, in my case I selected a Funduino pro mini, but any version will do:Ī power supply for the arduino and sensor module: during tests I just supplied the arduino through a USB-FTDI cable (see here), which was also used to program the arduino. An Arduino is just fine to perform these continuous readouts, implement the counting of the total number of turns, and send this data over a wireless link to some logging server: Putting an LED and photodiode above the border of this wheel allows to detect each turn of the wheel, simply by detecting the variations in reflected light. The interesting part is the half-red/half-silver wheel that spins when water flows through the meter. building a custom readout device, attached where the proprietary add-on is supposed to go: I used this project as an opportunity to experiment with wireless sensors, especially after discovering a ton of interesting usecases on the site.buying the sensor add-on specifically designed to go with my model of water meter (“HRI pulse unit” for Sensus 620): not intrusive, it plugs on top of the original meter, it is however expensive and requires a specific proprietary data acquisition system to read the data.Also, it requires replacing the original water meter, which I am pretty sure my water company would not allow. replacing the existing meter with a new one equipped with data transmission capability: such meters are expensive, and must generally be associated to even more expensive data acquisition/transmission systems.The purpose of this project was to have a way to monitor our water consumption at home, with minimal modifications to the existing installation.