Types of level measurement transmitters
There are various types of level measurement transmitters available, each utilizing different principles and technologies to measure and monitor the level of liquids or bulk materials. Here are some common types of level measurement transmitters:
Differential Pressure (DP) Transmitters:
- These transmitters work based on the principle of hydrostatic pressure. They measure the pressure difference between the bottom of the tank or vessel and the liquid surface. The pressure difference then converted into a level measurement. DP transmitters widely used and suitable for a range of applications.
Ultrasonic Level Transmitters:
- Ultrasonic transmitters use high-frequency sound waves to measure the level of liquid or solid materials. They emit ultrasonic pulses towards the liquid or solid surface and measure the time it takes for the echo to return. By calculating the time of flight, the level determined. Ultrasonic transmitters are non-contact and used in various industries.
Radar Level Transmitters:
- Radar transmitters utilize radar waves to measure the level of liquids or solids. They emit microwave signals that reflect off the surface of the material, and the time it takes for the signal to return is used to calculate the level. Radar transmitters are suitable for challenging environments with dust, vapors, or extreme temperatures.
Capacitance Level Transmitters:
- Capacitance transmitters work based on the change in capacitance between two electrodes as the level of the liquid or material changes. As the level increases or decreases, the capacitance changes, and the difference converted into a level measurement. Capacitance transmitters commonly used for liquids and solids with a dielectric constant.
Guided Wave Radar (GWR) Transmitters:
- GWR transmitters use guided microwave signals that travel along a probe or waveguide. The signals reflect back when they encounter the liquid or solid surface, and the time of flight used to determine the level. GWR transmitters are suitable for liquids, slurries, and solids.
Magnetic Level Transmitters:
- Magnetic transmitters use a float equipped with magnets that move up and down with the liquid level. The movement of the float changes the magnetic field, which is then detected and converted into a level measurement. Magnetic transmitters often used for continuous level measurement in tanks or vessels.
Hydrostatic Pressure Transmitters:
- These transmitters measure the hydrostatic pressure exerted by the liquid column above the sensing element. The pressure converted into a level measurement using the hydrostatic pressure formula. These transmitters are suitable for liquids and used in open tanks or closed vessels.
These are just a few examples of level measurement transmitters, and there are other specialized types available as well. The selection of a specific type depends on factors such as the nature of the material, operating conditions, accuracy requirements, and installation considerations.