Water flow sensor is mainly consists of plastic valve body, rotor assembly and Hall Current Sensor.It is installed in the hot water inlet end for detecting water flow. When water through the flow rotor assembly, Magnetic rotor will rotate and Speed will change as the flow change. Hall Current sensor output corresponding pulse Signal and feedback to controller, then the controller will control the flow. Features: Lght weight, easy to installSuitable for -type electric water heater and water-storage type electric water heaters' water power controlWhen water flows within the flow switch, and water flow ≥1.0L / min, the magnetic core in the flow switch driven by the push of water starts to move; the core's displacement causes magnetic effect and makes flow switch output "ON" signal. The signal inputs device control system, the control system finishes control action; when the water flow is less than the beginning flow, the flow switch output "OFF" signal. The control system will generate reverse control action.Water flow - ON; No water flow - OFF Specification: The lowest rated working voltage: DC 5V-24VMaximum operating current: 0.5AMaximum load current: 1.0AMaximum load power: 10WMaximum contact resistance: 100m&;Maximum switch voltage: 110V DCMinimum collapse voltage: 220V DCStart water flow: ≤1.0 L / min Working Flow Range: 1-25L / minStart pressure: ≤0.1MpaMax. pressure: 2.0MpaMin. pressure: ≤1.75MpaWork temperature: 1- 120 Ambient temperature: -40~150Span: 180 times (switching cycle)Work humidity range: 35%~90%RH (no frost)Allowing pressure: pressure 1.75MpaStorage temperature: -25~+80 ° cSave humidity: 25%95%RHResponse/Release time: 0.2sDimension(L*D): Approx. 53mm*22mm/2.09x0.87inchCable length: Approx. 35cm/13.78inchInput/Output Screw Diameter: Approx. 20mm/0.79inchColor: Black Package Includes: 1 x Water flow Switch