Non-contact liquid sensors use a capacitive technique to detect stationary or flowing liquids in pipes or tanks. Because they are using capacitance, they only work through plastics or glass and will not work on metal pipes.
The Icstation XKC-Y26-V sensor pictured here works with 5V to 12V dc, can switch 200mA maximum (using an NPN transistor) and has a response time of approximately 500mS. It also features adjustable sensitivity.
We are currently testing this sensor to detect when our rain water harvesting system is collecting rain water.
