概要
Level meters, also known as level gauges, are used in all industries to measure the level of a liquid. The most common level meters are float, bubbler, capacitive, ultrasonic, hydrostatic and laser.
Float level meters are the simplest and most economical method of level measurement. The primary principle is that a float, anchored to a stem, rides with the liquid’s surface. The stem is connected to a mechanism that indicates the level on a mechanical or electronic gauge.
Bubbler level meters measure the level of a liquid using pressurized air bubbles. Pressure is applied to a transmission line and is regulated to a specific pressure. When the level increases, the pressure of the air bubbles is reduced, allowing them to rise. The pressure is then monitored and used to determine the level.
Capacitive level meters measure the level of a liquid using two electrodes. The electrodes are connected to a power source and the capacitance of the liquid is measured. When the level of the liquid rises, the capacitance between the electrodes increases, which allows the reading of the level.
Ultrasonic level meters measure the level of a liquid using sound waves. An ultrasonic transmitter emits sound waves that travel through the liquid and are reflected by the surface. The reflected waves are measured and the level is calculated.
Hydrostatic level meters measure the level of a liquid using pressure. The pressure is determined by the weight of the liquid column. A pressure transmitter is connected to a pressure port and the pressure is monitored. The level is calculated from the pressure.
Laser level meters measure the level of a liquid using laser technology. A laser beam is directed down the sight tube and the reflected light is used to measure the level. The laser light is interrupted when it reaches the surface of the liquid, allowing the level to be determined.
Level meters come in a variety of shapes and sizes to suit a wide range of applications. Their range of operation may vary, depending on the type of level meter being used. Some level meters may be suitable for measuring the level of very small amounts of liquid whilst others may be capable of measuring extremely high levels. Hard-wired and wireless technologies are available, giving users maximum flexibility when choosing their level meters.
