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Intelligent liquid turbine flowmeters can only measure single-phase fluids with low viscosity and low corrosivity. They consist of a turbine, bearings, a pre-reducer, and a display instrument. Intelligent liquid turbine flowmeters are used for measuring liquid media; although turbine flowmeters can also be used to measure gases, their external structure differs from that of liquid turbine flowmeters. Since gases are greatly affected by temperature and pressure, in some cases, temperature and pressure compensation devices must be used when measuring gases at high temperatures in order to improve the accuracy of the measurement data. When the fluid under test flows through the turbine flowmeter sensor, it impacts the turbine blades, causing the turbine to rotate. The speed of rotation of the turbine changes as the flow rate changes; in other words, the higher the flow rate, the faster the turbine rotates. The speed of rotation is then converted into electrical pulses of corresponding frequency using a magnetoelectric converter. After being reduced in amplitude by a pre-amplifier, these pulses are sent to a display instrument for counting and showing. The instantaneous flow rate and cumulative flow rate can be determined based on the number of pulses per unit time and the total number of pulses accumulated. Wiring requirements for intelligent liquid turbine flowmeters (1): When selecting the cable length, make sure to use a single, complete cable whenever possible ； (2) The wiring should be placed as far away as possible from sources of electrical noise (such as high-power transformers, motors, and strong power cables), and it should be avoided to run parallel to power supply cables ； (3) Advocate the use of non-soldered clamping terminals at the ends of thick wires. (4) To prevent water ingress and mechanical damage, cables should be placed in metal conduits as much as possible; however, high-power transmission cables should not be placed in the same conduit. (When the maximum power that can be transmitted by one cable is 10 times greater than the minimum power transmitted by the flow meter signal cable, the two cannot be installed in the same conduit.) ； (5) In areas with a strong external magnetic field, the axis of the detection installation should be perpendicular to the direction of the magnetic flux from the external field, or the flow sensor or related components should be shielded using highly magnetic materials ； (6) The connection of the cable for the explosion-proof intelligent turbine flowmeter sensor must strictly comply with the relevant standards for explosion-proof reducers. Like other flowmeters, when installing a turbine flowmeter it is important to keep it away from sources of disturbance and avoid installing it on vibrating pipes. The installation location should be chosen so that the sensor of the flowmeter is in a condition of full flow. The following installation considerations are particularly important: (1) Since there are stationary components outside the turbine flowmeter, high standards are required regarding the cleanliness of the fluid. To prevent impurities in the fluid being measured from affecting the instrument, a filter should be installed before the flowmeter to ensure the fluid’s cleanliness. The filter can be funnel-shaped, and its mesh size depends on the level of impurities in the fluid; it is usually between 20 and 60 mesh. The filter needs to be cleaned regularly to maintain its cleanliness. The timing for cleaning can be determined by measuring the pressure difference across the filter. The specific procedure is as follows: the filter that comes with the turbine flowmeter ； P1 and P2 are the pressure measurement points before and after the filter; the pressure difference between these two points is measured using pressure conduits in order to assess the cleanliness of the fluid flowing through the pipeline. If the pressure difference increases, it indicates that the fluid is not clean. Once the pressure difference reaches a certain level, it is necessary to disassemble the filter for cleaning and to review the properties of the fluid used in the process. (2) Turbine flowmeters have certain requirements for the straight pipe sections upstream and immediately upstream of them. For industrial applications, the required lengths of straight pipe are 20D upstream and 5D upstream; to eliminate secondary flows, it is advisable to install flow straighteners at the upstream end as much as possible. If a straight pipe section of about 10D can be ensured at the upstream end, and a flow rectifier is installed, the measurement accuracy of the flow meter can reach the accuracy level obtained during calibration. (3) Turbine flowmeters can only measure single-phase media; therefore, when measuring liquids, it is necessary to prevent air or vapor from entering the instrument. When the fluid contains free gas, a degasser should be installed upstream of the instrument if necessary. For liquids that are prone to vaporization, a sufficient back pressure must be ensured upstream of the flowmeter. The value of this back pressure can be set as twice the pressure drop across the flow meter at maximum flow, plus 1.2 times the vapor pressure of the liquid being measured at the lowest temperature; it is also important to ensure that the entire piping system is properly sealed.