Radar level transmitter

Radar level transmitter is a device used for the measurement of liquid levels. Due to their high precision and accuracy, these radar type level transmitters are widely used commercially.

Working principle

The working principle of radar level transmitters is very much similar to the ultrasonic level transmitter and the only difference is that radar level indicators make use of radio waves instead of ultrasonic waves. This transmitter consists of three parts.

• 1- A transmitter
• 2- An antenna
• 3- A signal receiver

This transmitter is attached to the top of the tank that contains the liquid to be measured. The transmitter part of this device emits waves known as radio waves and is very much similar to microwaves. As soon as these electromagnetic waves strike the surface of liquid they are reflected in the opposite direction. These waves, in turn, enter the antenna and are sensed by the receiver. The time of flight i.e the time taken by these waves to travel the given distance is then used to calculate the level of the liquid.

Types of radar level transmitters

Some radar level use waveguides to guide the waves in a proper direction of liquid in the tank whereas others simply emit these high-frequency waves in an open space. Based on this difference these transmitters are divided into two types.

1- Guided wave radar level transmitter

These transmitters employ guide waves for directing the radio waves and help in combating the wave loss. They channel the waves in a straight line towards the liquid surface and thus help in precise measurement.

2- Non-contact radar level transmitter

Noncontact radar transmitters make use of their antennas to direct the waves and also to receive them. Therefore these transmitters offer a chance for signal loss. These transmitters are however simpler in their structure and signal propagation occurs in an open space.

Features

• ✔ Continuous level sensor-Radar emits electromagnetic waves, and the probe is hardly affected by temperature, pressure, gas, etc.
• ✔ Wide applications-can be used to measure liquid, slurry,grains,solids,powder.,etc
• ✔ Noiseless and self-adjustable sensing ability
• ✔ Higher accuracy in measurement for up to a distance of 100 ft.
• ✔ The transmitters can vary the amplitude of waves.
• ✔ They can also analyze the shape of the echo.
• ✔ The shape of the tank and other environmental features don’t affect the measurement.

Applications of Radar level transducer

The non-contact and top-down installation and accuracy of measurement make it a very useful level measuring device. Thus these transmitters are used in food processing industries, water and fuel management, mining industries, acid management industries, saline, and wastewater management and other industries. These level transmitters are highly capable of measuring the level of corrosive and clean liquids in tanks.

Level sensor for solids 

Radar level transmitter is also a kind of level sensor for solids, it can measure bulk solids, powder, grain, ore,granular solids, sludge blanket.,etc in a silo, tank,  powder hopper  or other vessel  ,it is a kind low cost solids level transmitter for continuous level detection. 26G Hz radar is a kind of reliable solid level measurement technologies, the level measurement not affected by solids temperature, pressure, dust, or noise.

Guided wave radar level transmitter

Overview of guided radar type level transmitter

This transmitter is radar type level transmitter that utilizes a guided wave for the emission of the electromagnetic waves from the transmitter. The aim of using a guided wave radar is to properly channel the waves in order to avoid any signal loss that can affect the measurement. This radar level sensor is installed on the top side of the tank and a probe is immersed into the liquid. Thus it is not a noncontact type of level measuring device. The waves are emitted down the level probes and when they strike the surface of liquid they reflect backward within the confines of the probe. The overall working principle is the same as radar level transmission.

Applications of GWR level transmitter

The controlled guiding of the electromagnetic waves prevents the loss of signals and thus the accuracy of measurement is greatly increased. This guided wave radar level sensor finds its great application for interface level measurement of liquids like water and oils and it also measures through the foams. These devices are not affected by high density, temperature, and pressure, and this quality favors wide applications. The key usage of these transmitters is employed in oil, gas, petrochemical and other process industries.