The main technologies used to measure the level of solids, their operating principle, advantages, disadvantages and applications are detailed below:
1. Rotary Vane Level Sensors
They operate by means of a paddle that rotates inside the tank. When the level of solids reaches the paddle, the motor stops due to the resistance of the material, indicating the presence of the solid.
2. Vibrating Level Sensors
These sensors use a probe that vibrates at a specific frequency. When the solid covers the probe, the vibration frequency changes, indicating the level reached.
3. Ultrasonic Level Sensors
Ultrasonic waves are emitted towards the surface of the solid material. The time it takes for the echo to return to the sensor is converted into a distance measurement.
4. Radar Level Sensors
They use high-frequency radio waves that bounce off the surface of the solid material. The distance is calculated by measuring the time it takes for the echo to return to the sensor.
5. Capacitive Level Sensors
They detect changes in capacitance when the solid material is in contact with the sensor or approaches it.
6. Laser Level Sensors
They use a laser beam directed at the surface of the material. The time it takes for the laser to reflect back is converted into a level measurement.
7. Guided Microwave Level Sensors (TDR)
They work by sending microwave pulses along a guide probe. The reflection time of the waves, caused by contact with the material, allows the level to be measured.
8. Weighing Level Sensors
They use load cells to measure the total weight of the tank. With this information, the material level is calculated.
