1/2" Water Flow Sensor Food-Grade Switch Hall Effect Flowmeter Fluid Meter Counter 1-30L/min

I haven't finished integration, but initial tests are very positive.I am running this meter on 3v and so far it's working great. I think there's a small paddlewheel inside that spins to count flow; I don't have measurements on precision yet, but the numbers I'm seeing show it to be quite sensitive indeed.I've connected it to a SEEED Xiao ESP32C3, and configured it with ESPHome as a pulse counter, and then integrate that pulse counter into a volume measurement. I still have some work to do on the calibration, but very pleased with this so far.I haven't compared it to others, and I think there are some improvements to be had in sturdiness (it's cheap plastic, but that's obvious from the photos), but overall I am excited to have a working meter.

Works. Definitely seeing the +/- 5% difference in output.A few things I discovered:* The sensor needs at least 8V. I had a 9v power supply left over from some other equipment. However, a raspberry PI can only take 3.3V into its GPIO port. (and no pull-up resistor is needed) So I sent 8V into this sensor, and on the output pin I installed a 10k resistor tied to ground. This dropped the output voltage to around 3.7V.* I wanted to record data in gallons per hour. This is from my most recent calibration where I dumped water into a bucket marked off with quarters of a gallon on the side.total_gal = total_gal + 0.001115 # 897 pulses per gal = 0.001115 gal per pulse. This code runs whenever a change from high to low occurs on the output pin.flow = (count / 897.0)*3600 # pulses/897 is gal per sec. *3600 is gal per hour* the label faces down. There is a lot of play in the spindle inside. making the label face down puts the impeller more directly in line with the water flow* make sure you install it in the right direction. The arrow on the label was correct for me.* I used waterproof automotive plugs, sealed on the ends with caulk, since this thing will be outside measuring the irrigation water usage.

The price was good and seemed to work as described but have not run calibration tests yet. I was able to find online programming and application information but it would have been nice to provide links to technical data sheets and programming examples.

Perfect for my DIY water usage monitoring system. Accurate readings, durable build, and easy integration with my Arduino project. Threads were clean and fit standard fittings with no leaks. Will be ordering more

This flow sensor is very noisy and not accurate above 37l/ minute (10 Gallons/minute). It is 30% off, not really useful. I tried two, they were the same.The noise caused by the sensor impeller at medium to high flow is also very annoying because it is heard through the whole house as it is carried by the piping.Make sure you know what is the flow rate you are going to measure. If it is bellow 7 Gallons/minute you can give it a try. For higher flow rate look elsewhere.

I've adapted this Gredia GR-201 1/2" flow sensor paired with a Digiten Flow Meter to monitor flow rate thru a UV sterilizer. The sterilizer I have requires a flow at 37 GPH optimum and 60 GPH max to be effective eradicating protozoa.Out of the box the pairing of the meter and sensor was way off reporting 16 GPH while a had a gate valve nearly closed.So to calibrate it, the meter has a K-factor value that has to be adjusted to the sensor you pair it with. The default was a K-factor value of 1.98.I did a Google Bard search for what the sensors K-factor should be... 11.45. I set the meters K-factor to that. It was much closer but not accurate.I adjusted my valve until the meter was reading 1 GPH of flow. I set up a bucket to divert the water exiting the system into so I could measure the amount dispensed in a minute. I recorded .453 gal. with the K- 11.45.Now a little math, divide the current K- (11.45) by the flow it produced (0.453) while the valve restricted flow with the meter reading 1 GPM.The resulting new K-factor of 25.27 worked precisely. Well, as precise as using a large measuring cup to measure the amount of water dispensed.I re-ran the test, I got 1 gallon at the 1 minute mark, 3 gal at 3 minutes.The one annoying thing about the meter is the backlit display goes dark after 15 seconds. Annoying during the calibration when your hands are busy turning on/off a pump and a timer. But in actual use I'll only be using this to set the gate valve position and the backlighting won't so much be an issue.I hope this helps those trying to get a more accurate reading.