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. Can use for Water heaters, credit card machines, water vending machine, flow measurement device. Features: Lght weight, small size, easy to install. Inlaid with stainless steel impeller shaft, durable wearable. Seal Ring with the upper and lower force structure never leaks. Precautions: Non-violent shock, and chemical erosion. Non-throwing or hitting. Mounted vertically, should not exceed 5 degrees inclination. Temperature of Medium should not exceed 120 ? Cord Connection: Red: Positive(+) Yellow: Signal output. Black: Negative(-) Specification: Working voltage range: DC 3.5~12 v Working current range: 0.5-1.5mA Work temperature: 1- 100 ? Allowing pressure: ? 0.8Mpa Electric strength: >600VAC Insulation resistance: >100m? Storage temperature: -40~+100 ° C Flow Range :0.3-10L / min External threads: 3/8" Size (L x W x H): Approx. 5.4 x 3.6 x 2.5cm / 2.13 x 1.42 x 0.98 inch Output interface inner diameter: Approx. 0.9cm / 0.35 inch Cable length: Approx. 15cm / 5.9 inch Color: White Material: plastic Package Includes: 1 x 0.3-10L/ min Water flow Sensor