Hi guys, I have been searching for this water level sensor on the internet and i'm having no luck finding it. This is a water level sensor from a washing machine and i'm trying to sniff the signals to connect them to my arduino and know remotely what is the water level in real time.
This is a industrial washer. What i know so far:
The ground is the first pin
The other pins measure 2.5V , 5V, 2.5V
irrespectively of the water level the pins will always measure the same
All of the other water level sensors i have seen online have only 3 pins, i couldnt find one with 4
If you have any lead to where i could ind more info or if you have some info let me know. Thanks in advance.
Most washers use an air pressure sensor to measure water level.
With four pins, and those voltages, that is most likely a Wheatstone bridge. The voltage on the two ~2.5V pins will change in opposite directions as the pressure increases, perhaps by only a few mV.
An instrumentation amplifier module can be used to interface with it, also a strain gauge amplifier like the HX711 should work.
I agree.
The chip next to it is probably a HX710 (or equivalent), the smaller sister of the HX711.
Are you sure it's broken. A comon problem with washing machines is that the hose itself is blocked. Try to blow through the hose.
Leo..
@jremington Thanks, thats a good help, i will research more based on that and make some tests
@Wawa Fortunately its not broken, i want to learn how this thing works so i can get the water level on my arduino
@Railroader I have multiple washing machines and want to monitor the water level of each one, in case some is below water level it will trigger a warning
The output of the chip is likely digital, and not easy to read.
You could start with measuring the differential voltage between the two 2.5volt pins.
The difference could be about 0-40mV, depending on water level.
Take care.
The machine could have a capacitive (not isolated) power supply.
All parts could be live all the time.
Leo..
