What is a Tank Level Sensor and How Does it Work?

A tank level sensor is a device that is used to measure the level of liquid in a tank or container. These sensors can be used in a variety of industries, including oil and gas, water treatment, chemical processing, and many others.

There are several different types of tank level sensors available, including float sensors, ultrasonic sensors, pressure sensors, and radar sensors. Each type of sensor works in a slightly different way, but all are designed to provide accurate and reliable measurements of liquid level.

Float sensors, for example, use a float that is attached to a metal rod or cable. As the level of liquid in the tank rises or falls, the float moves up or down, which causes the rod or cable to move as well. This movement is then transmitted to a sensor, which converts it into an electrical signal that can be used to determine the level of liquid in the tank.

Ultrasonic sensors use sound waves to measure the level of liquid in a tank. The sensor emits a sound wave that travels through the liquid and reflects off the surface of the liquid back to the sensor. The time it takes for the sound wave to travel to the surface and back is used to determine the distance between the sensor and the liquid surface, which can be used to calculate the level of liquid in the tank.

Pressure sensors work by measuring the pressure at the bottom of the tank. As the level of liquid in the tank rises or falls, the pressure at the bottom of the tank changes. This change in pressure is detected by the sensor and converted into an electrical signal that can be used to determine the level of liquid in the tank.

Radar sensors use radar technology to measure the level of liquid in a tank. The sensor emits a radar signal that travels through the air above the liquid and reflects off the surface of the liquid back to the sensor. The time it takes for the radar signal to travel to the surface and back is used to determine the distance between the sensor and the liquid surface, which can be used to calculate the level of liquid in the tank.Tank level sensors are an important tool for accurately measuring the level of liquid in tanks or containers. By using a variety of sensing technologies, these devices provide reliable and accurate measurements that are critical for ensuring proper operation and maintenance of industrial processes and systems.

Tank Level Sensors Types

There are several types of tank level sensors, each with its own advantages and disadvantages. Here are some of the most common types:

Float Level Sensors 

The float level sensors use a float attached to a lever to measure the level of liquid in the tank. As the level of liquid rises or falls, the float moves up or down and the lever translates this movement into a measurement signal.

Ultrasonic Level Sensors

Ultrasonic level sensors use sound waves to measure the level of liquid in the tank. An ultrasonic transducer sends a sound wave pulse toward the surface of the liquid, which reflects the wave back to the transducer. The time it takes for the wave to return is used to calculate the level of liquid.

Capacitance Level Sensors

Capacitance level sensors use changes in electrical capacitance to measure the level of liquid in the tank. The sensor is mounted at the top of the tank and sends an electrical signal to a probe that extends into the liquid. As the level of liquid rises or falls, the capacitance between the probe and the tank changes, providing a measurement signal.

Pressure Level Sensors

Pressure level sensors use changes in pressure to measure the level of liquid in the tank. The sensor is mounted at the bottom of the tank and measures the pressure of the liquid. As the level of liquid rises or falls, the pressure changes, providing a measurement signal.

Radar Level Sensors

The radar level sensors use radar waves to measure the level of liquid in the tank. A radar signal is sent toward the surface of the liquid, which reflects the wave back to the sensor. The time it takes for the wave to return is used to calculate the level of liquid.

Optical Level Sensors

Optical level sensors use infrared or laser light to measure the level of liquid in the tank. An emitter sends light toward the surface of the liquid, and a receiver detects the reflected light. The amount of reflected light provides a measurement signal.

Each type of sensor has its own benefits and drawbacks, and the appropriate sensor to use depends on the specific application and the characteristics of the liquid being measured.

What Should You Think Before Do Tank Level Measurement?

Before measuring tank level, there are several important factors to consider to ensure accurate and reliable measurements:

Tank Geometry and Material: The shape and size of the tank, as well as the material it is made of, can affect the accuracy of the measurement. Tanks with irregular shapes or that are made of materials that can interfere with the measurement signal may require special sensors or calibration.

Liquid Properties: The properties of the liquid being measured can also affect the accuracy of the measurement. Viscosity, density, and temperature can all impact the way the liquid behaves in the tank and how it interacts with the sensor.

Measurement Range: It is important to choose a sensor that can measure the full range of the liquid level in the tank. Sensors that are too small or too large for the tank can lead to inaccurate measurements or damage to the sensor.

Mounting and Installation: Proper mounting and installation of the sensor is crucial for accurate measurements. The sensor should be installed at the correct location and height in the tank, and any obstructions or interference should be avoided.

Calibration: Calibrating the sensor is essential to ensure accurate measurements. Calibration should be done regularly, especially if there are changes in the tank or liquid properties.

Safety: Before measuring tank level, it is important to ensure that the tank is safe to access and that all necessary safety precautions have been taken. This may include wearing appropriate personal protective equipment and following any relevant safety procedures.

Careful consideration of these factors can help ensure accurate and reliable tank level measurements, which can be critical for a variety of applications.

The Tank Level Measurement Environments You will Face

Tank level measurement environments can vary widely depending on the application, and can present a range of challenges that must be considered when selecting a sensor or measurement technique. Some common tank level measurement environments include:

Hazardous Environments: Tanks containing flammable, explosive, or toxic materials may require special sensors and safety precautions to ensure safe and accurate measurement.

High or Low Temperatures: Tanks containing liquids at high or low temperatures may require sensors that are designed to withstand extreme temperatures or that use cooling or heating elements to protect the sensor.

Corrosive Environments: Tanks containing corrosive liquids may require sensors that are made from materials that are resistant to corrosion, or that use protective coatings or barriers to prevent damage to the sensor.

Dirty or Contaminated Environments: Tanks containing liquids with high levels of contaminants, such as sediment or debris, may require sensors that are designed to avoid interference from the contaminants or that use filtration systems to remove them.

High Pressure or Vacuum Environments: Tanks that are under high pressure or vacuum may require sensors that can withstand the extreme forces and provide accurate measurements under these conditions.

Outdoor Environments: Tanks that are located outdoors may be subject to extreme temperatures, humidity, or exposure to the elements, which can affect the accuracy and reliability of the sensor.

Selecting a sensor or measurement technique that is appropriate for the specific tank level measurement environment is essential to ensure accurate and reliable measurement.

Tank Level Sensor Industries & Applications

Tank level sensors are widely used in many different industries and applications where the measurement of liquid levels is important. Some common industries and applications for tank level sensors include:

Oil and Gas: Tank level sensors are used to measure the level of oil, gas, and other fluids in tanks and storage containers in the oil and gas industry.

Chemical and Pharmaceutical: In the chemical and pharmaceutical industries, tank level sensors are used to measure the level of chemicals, solvents, and other liquids in tanks and vessels.

Water and Wastewater: Tank level sensors are commonly used in water and wastewater treatment facilities to monitor water levels in tanks and reservoirs.

Food and Beverage: In the food and beverage industry, tank level sensors are used to measure the level of liquids such as milk, juices, and beer in storage tanks and vats.

Agriculture: Tank level sensors are used in agriculture to measure the level of liquid fertilizers, pesticides, and other chemicals in storage tanks.

Automotive: Tank level sensors are used in automotive applications to measure the level of fuel in gas tanks.

Marine: In marine applications, tank level sensors are used to monitor the levels of fuel, water, and other fluids in tanks on ships and boats.

Tank level sensors are used in a wide range of industries and applications where the measurement of liquid levels is important for safety, quality control, and process optimization.

How do you calculate the liquid level in a vessel?

The calculation of liquid level in a vessel depends on the shape and dimensions of the vessel. Here are some common methods used for calculating the liquid level in vessels:

Sight glass: A sight glass is a transparent tube or window installed on the side of the vessel that allows the operator to visually inspect the liquid level. The sight glass is marked with calibrated indicators that provide an estimate of the liquid level.

Dipstick: A dipstick is a simple tool that can be inserted into the vessel to measure the liquid level. The dipstick is marked with calibrated indicators that show the level of liquid in the vessel.

Pressure measurement: Pressure measurement is a commonly used method for measuring the liquid level in closed vessels. The pressure at the bottom of the vessel is measured, and the liquid level is calculated based on the pressure reading and the specific gravity of the liquid.

Ultrasonic level measurement: Ultrasonic level measurement is a non-invasive method that uses ultrasonic waves to measure the distance between the liquid surface and the top of the vessel. The distance is then converted to a liquid level measurement.

Radar level measurement: Radar level measurement is a non-contact method that uses radar waves to measure the distance between the liquid surface and the top of the vessel. The distance is then converted to a liquid level measurement.

Overall, the method used for calculating the liquid level in a vessel depends on the type of vessel, the specific requirements of the application, and the accuracy required for the measurement.