The water flow sensor mainly consists of a copper valve body, a water flow rotor component, a steady flow component, and a Hall element. It is installed inwater heaterThe inlet end is used to measure the inlet flow rate. When water flows through the rotor component, the magnetic rotor rotates and the speed changes linearly with the flow rate. Hall element outputs correspondingpulse signalFeedback to the controller, which determines the size of the water flow rate and adjusts the controlproportional valveThe current is controlled by a proportional valve to regulate the gas volume and avoidgas water heaterDuring use, there is a phenomenon of warm summers and cool winters.

advantage

The water flow sensor fundamentally solves the problem of differential pressureWater gas linkage valveThe disadvantages of high startup water pressure and prone to misoperation of the flap type water valve, such as dry burning. It has sensitive response, long lifespan, fast action, safety and reliability, easy connection, and ultra-low startup flow(1.5L/min)Such advantages are deeply loved by a large number of users.

working principle

The water flow rotor assembly mainly consists of a turbine switch housing, a magnetic rotor, and a brake ring. usewater flow switchIn terms of performance, it outperforms mechanical differential pressure disc structures and significantly reduces in size. When water flows through the turbine switch housing, it drives the magnetic rotor to rotate. When different magnetic poles approach the Hall element, the Hall element conducts, and when they leave, the Hall element disconnects. Thus, the rotor speed can be measured. Based on the measured water flow rate, rotor speed, and output signal(voltage)The curve can determine the starting water pressure of the water heater, as well as the corresponding starting water flow rate and rotor starting speed for the starting water pressure. By controlling the circuit, it is possible to start the water heater when the rotor speed is greater than the starting speed;When the speed is lower than the starting speed, the water heater stops working. In this way, the starting water pressure of the water heater is generally set at0.01MPaThe starting water flow rate is3~5L/min(Need to meet the maximum temperature rise limit of the water heater standard)In addition, due to the magnetic field cutting of the permanent magnet material, water becomes magnetized water, and the oxygen content in the water increases, making people feel refreshed after bathing. The function of the brake ring is to stop the high-speed rotating magnetic rotor from rotating and terminating when the water is stoppedpulse signalOutput. The controller cannot receive the pulse signal and immediately controls the gasproportional valveClose the valve, cut off the gas source, and prevent dry burning.

Selection techniques

Firstlyaccuracy classThe accuracy level of water flow sensors is usually relatively high, and in general, the higher the accuracy, the more sensitive they are to the on-site application environment. From an economic perspective, do not blindly seek high precision levels. For situations with large caliber flow, such as in the West East Gas Pipeline Project, high-precision sensors should be selected, while for situations with small transport volumes that require measurement, conventional sensors can be selectedTurbine flow sensor.

Secondly, density. The stability of density has a significant impact on the measurement accuracy of water flow sensors. For situations where density is often changed, it is necessary to considerflow coefficientAdopting corrective measures for handling, especially for low traffic areas.

Thirdly, the scale of traffic. The selection of flow scale for water flow sensors directly affects their performanceaccuracyAnd the service life also determines the selection of flow sensor caliber. The selection of traffic scale is usually based on the following principles:The minimum flow rate should begreater than or equal toThe minimum flow rate that can be measured by appearance should be less than or equal to the maximum flow rate that can be measured by appearance;For situations where uninterrupted work is less than eight hours, the maximum flow rate should be the actual maximum flow rate1.3About times;For situations where uninterrupted work exceeds eight hours, the maximum flow rate should be the actual maximum flow rate1.4More than double;The minimum flow rate should be the practical minimum flow rate0.8Double is the best.

Fourth, loss of pressure. The smaller the pressure loss, the lower the energy consumption of gas during activity, which can save energy, reduce transportation costs, and improve utilization efficiency. So when choosing, try to choose those with less pressure lossTurbine flow sensorUsually, half is chosenEllipsoidfrontflow guideThe pressure loss of the turbine flow sensor is smaller than that of the front diffuser of the cone.

Fifth, layout method. The layout method is determined by using the above three methods:The best choice for internal layout is the reverse thrust turbine flow sensor, as this layout can keep the impeller in a floating state within a certain flow scale, with no contact points in the axial direction, no end face conflicts or wear, and can extend the service life of the bearing;Regarding the flow sensor of the horizontal layout device, its connection method with the pipeline can be flange connection, threaded connection, or clamping connection;Only threaded connections can be used for flow sensors with straight layout devices

selection

In the need for a more accurate water control systemThe water flow sensor will be more useful and intuitive to use. withpulse signalTaking the output water flow sensor as an exampleInICwater meterHigher water and electricity heating environments are required for flow controlWater flow sensors have stronger advantages. togetherdue toPLCConvenience of operationThe linear output signal of the water flow sensor can be directly connectedPLCEven achieving correction and compensationQuantitative control and electrical switching can be performed. Therefore, in some relatively higher water control systemsThe application of water flow sensors is gradually replacingwater flow switchWith the sensing function of the water flow switch, it also satisfies the need for water flow measurement.

Precautions

Precautions for the use of water flow sensors

1When magnetic data or sensors are affectedmagnetic forceWhen the data approaches the sensorIts characteristics can be altered.

2To prevent particles and debris from entering the sensorIt is necessary to install a filter screen at the inlet of the sensor.3The device of water flow sensor should avoid environments with strong sensation and shakingPrevent affecting the measurement accuracy of the sensor.