The intelligent liquid turbine flowmeter is a new type of intelligent instrument that integrates the turbine flow sensor and display integration, which is developed by using advanced ultra-low power single-chip microcomputer technology. It has compact structure, intuitive and clear reading, high reliability, and is not interfered by external power sources. , Anti-lightning, low cost and other obvious advantages.
A flow meter that uses a turbine for measurement. It first converts the flow rate into the rotational speed of the turbine, and then converts the rotational speed into an electrical signal proportional to the flow rate. This kind of flowmeter is used to detect instantaneous flow and total integrated flow, and its output signal is frequency, which is easy to digitize. In the figure, the induction coil and the permanent magnet are fixed on the shell together. When the ferromagnetic turbine blade passes the magnet, the reluctance of the magnetic circuit changes, thereby generating an induction signal. The signal is amplified and shaped by the amplifier, and sent to the counter or frequency meter to display the total accumulated flow. At the same time, the pulse frequency undergoes frequency-voltage conversion to indicate instantaneous flow. The speed of the impeller is proportional to the flow, and the number of revolutions of the impeller is proportional to the total amount of flow. The output of the turbine flowmeter is a frequency modulated signal, which not only improves the anti-interference of the detection circuit, but also simplifies the flow detection system. Its turndown ratio can reach 10:1, and the accuracy is within ±0.2%. The time constant of the turbine flowmeter with small inertia and small size can reach 0.01 second.
Turbine flowmeter is the main type of velocity flowmeter. When the measured fluid flows through the turbine flowmeter sensor, under the action of the fluid, the impeller is rotated by force, and its speed is proportional to the average flow velocity of the pipe. At the same time, the blades are periodic Ground cutting of the magnetic field lines generated by the electromagnet changes the magnetic flux of the coil. According to the principle of electromagnetic induction, a pulsating electric potential signal, that is, an electric pulse signal, is induced in the coil. The frequency of the electric pulse signal is proportional to the flow rate of the fluid to be measured.