Plug-in ultrasonic flowmeter features
Programmable frequency low frequency rectangular wave excitation improves stability of flow measurement and low power loss;
Using 16-bit embedded microprocessor, the operation speed is fast and the precision is high;
Full digital processing, strong anti-interference ability, reliable measurement, high precision, flow measurement range up to 100:1;
Ultra-low EMI switching power supply, suitable for wide range of power supply voltage and good anti-EMC performance;
Full Chinese character menu operation, easy to use, easy to operate, easy to learn and understand;
High definition backlit LCD display;
It has two-way flow measurement and two-way total accumulation function, and the current and frequency have bidirectional output function;
There are three totalizers in the internal to display the forward cumulative amount, the reverse cumulative amount and the difference integrated amount;
With RS485 or RS232 digital communication signal output
It has a conductivity measurement function to determine whether the sensor is empty or not;
The constant current excitation current range is large, and can be used with different companies and different types of electromagnetic flow sensors;
With self-test and self-diagnosis function;
High reliability with SMD devices and surface mount (SMT) technology;
The internal design of the meter has a power-down clock that can record 16 power-down times.
Instruments that measure fluid flow are collectively referred to as flow meters or flow meters. The flowmeter is one of the important instruments in industrial measurement. With the development of industrial production, the accuracy and range of flow measurement requirements are getting higher and higher, and the flow measurement technology is changing with each passing day. Various types of flow meters have been introduced to suit various applications. More than 100 flow meters have been put into use. From different perspectives, flow meters have different classification methods. There are two commonly used classification methods. One is to classify according to the measurement principle adopted by the flowmeter: the second is to classify according to the structural principle of the flowmeter.
1. Sort by measurement principle
a. Mechanical principle:
Instruments belonging to such principles have differential pressure type, rotor type using Bernoulli's theorem;
Impulse type using the momentum theorem, movable tube type;
Direct mass equation using Newton's second law;
a target using the principle of fluid momentum;
Turbine using the angular momentum theorem;
Vortex type using vortex principle of fluid oscillation;
Use the total static pressure difference of the pitot tube type as well as volumetric and sputum, trough and so on.
b. Electrical principle:
Differential capacitor type,
Strain resistance type, etc.
c. Acoustic principle:
d. Thermal principles:
Indirect calorimetry and so on.
Pressure and temperature selection
The actual working pressure of the fluid in the pipeline should be less than the rated working pressure of the flowmeter. Pay attention to whether there is negative pressure in the pipeline, such as the evaporation process, and the negative pressure is up to -60KPa. Such working conditions should be communicated with the manufacturer's technicians when ordering. Strict requirements are imposed on the lining material. The actual temperature should meet the temperature requirements specified by the flowmeter.
Power supply selection
The choice of the electromagnetic flowmeter power supply should be selected according to the flowmeter itself and the environment of the site. If the site allows, the power supply is convenient, safe and easy to maintain. As a chemical company, more than 90% of the raw materials and process links are in the liquid phase. During operation, the internal humidity of the workshop is large, and no flammable gas is generated during the whole operation. It is safer to use DC24V for power supply. Outdoor dry environment, choose AC220V power supply, convenient lead wire, good maintenance and low cost.
Some explosion-proof occasions, such as flowmeters used in gas boilers, are ideal for battery-powered electromagnetic flowmeters.