6 Pieces Black Water Level Sensor Aquarium Tank Side Mounted Horizontal Liquid Float Switch

Works great with Arduino to control nutrient solution levels in hydroponic system. digitalRead(A0); returns "1" or "0." For my application, as sensor falls, a "1" is sent to the Arduino, which charges a DC-DC relay to activate normally closed solenoid valve until signal reads "0" again. I was hesitant to order after reading a lot of the reviews that insisted they go out after a short while, until I more closely examined the reviews. You cannot wire these directly between a source and a load (over about 5v) or they will predictably burn out! They are sensors, not switches, and as such must be "read" by another device that is then able to act upon it. As at least one other reviewer has noted, Arduino is a simple and safe platform for reading the signal and causing some other action based on the state of the sensor. If you need more info, Youtube it - "Arduino float switch"

Very simple reed switch. So far, all of them work great. The supply an input to a microcontroller. These are very low current switch, keepnthat in mind. If you are looking to directly use it as an inline switch, I would suggest using it to feed a MOSFET or opto-isolator. I would recommend using a SCR if it is for AC current

Works well for flood sensor on jobs. Just make sure you check continuity. Have had a couple bad out of the package.

I bought these to use and when they arrived, they were about twice as big as I was lead to believe, and so of no use to me. Other reviewers would have given these a 1 star rating and complained that they were too big. Just because they were too big for me has no bearing on the quality of the product, just the information on the site.

The sensors themselves work great so far and seem reliable.There are no instructions on how to properly install this so I had to dig around and look at other similar products and installation photos to figure it out. The photos show the silicone gasket backwards from what actually works. The flange goes on the inside, through the hole, then the nylon washer goes on, then the nut. These create a watertight seal on both sides.

Connected in series to a 12v motor pump. Set to turn on once the switch is flipped. It work for a few times during test but now seems to be permanent on position. I guess despite the switch seem water resistant but not when it is submerged in water.

I have used these switches in the past with good success. They are easy to use and can be installed to switch on or off depending on the orientation of the switch. I use these in 300 and 500 gallon water tanks to control the well pump. The switches feed the low current and voltage inputs to control relays and contractors.

Used these on my 300 gallon rain (barrel) collection system. Working great! Programmed a WeMos D1 Mini to provide five water levels, water temperature, and activation of an irrigation valve.