12V DC Water Level Controller Module Water Level Detection Sensor Automatic Liquid Control Switch PCB Board Supports Automatic Water Pumping/Filling/Draining

The instructions could be a little better, and better still if they were included and not just online. As my pump used more than 10 amps I used this board to run a automotive relay. Happy overall as this was a very cost effective option for me.

Works great for turning on a small pump to lower the water in a test tank. If you need to run a big motor pump use a big contactor to drive the motor and this board to drive the contactor.

Exactly what it looks like; it's a relay you hook up to a pair of sensors with a simple state machine that will maintain the water level in a tank between the low and high sensor by either draining or filling the tank, depending on how you hook it up to a pump.If the liquid in the tank is conductive enough, presumably you can just use wires as sensors. I did not try this; I used it to build a water tower to pressurize rain water which won't conduct much, so instead I just used aquarium water level sensors that close the circuit (connect) when the water level is at or above them to fulfill the same role.The only hiccup I had was the somewhat sparse documentation, though that is understandable given it is a very simple module. Specifically, the relay has no "off" -- you're supposed to connect your pump to ground and power through the relay to complete the circuit, using the central pin and then EITHER the "drain" or the "fill" pin. The way this works is that the board "remembers" whether it is filling or draining based on the sequence of the water level sensors.TL;DR you need to power it off and then on again whenever you change between draining and pumping, and if you manually trigger the sensors in a pattern that is not consistent with that mode, you may get odd results.Overall I am very happy with this item and would recommend it, I think you could use it for all sorts of things, not just pumps. Do understand that this is just a circuit board with some screw terminals; "some assembly required" would be an understatement. But it was exactly what I needed and it works great.

I use this module to partially drain and then fill my aquarium weekly. The module is basically a TWO state machine that uses the sense leads to determine when to energize the relay or not. It works consistently well. I've only used it for a couple weeks but no issues this far. See the illustration and write-up I made...that should help.

Used in a small arduino project. Been using for a few months now, have not encountered any issues. Good value, so far.

Functional looking board, but hand soldered. Plenty of resin in various spots, but no obvious solder bridges or cold joints. PCB printing looks clean with wide traces and simple, easily discernible layout. Shipped in an anti-static bag ONLY. No box, no spec sheet, no useable QR code, no website. Amazon put this in a box with lots of other (heavy) stuff I ordered at the same time. Between the build quality and the shipping, it will be a miracle if this thing works. Summer project, so we'll see.If you take a chance, order this by itself so it comes packaged singly.