Is a radar level meter a primary or secondary instrument?

Project Overview

　　Primary instrumentation is responsible for the direct detection of process variables such as temperature, pressure, flow and level, while secondary instrumentation is used to receive the output signal from the primary instrument and process, display or control it. For a long time, the question of whether radar level meters belong to primary or secondary instruments has confused many engineers or purchasers who are new to the industry. The purpose of this article is to clarify the classification of radar level meter, so that you no longer worry about this problem.

　　Radar level meter is a kind of non-contact level measurement instrument using microwave signals, by transmitting microwave pulses and receiving the reflected signals back, and calculating the level height according to the time difference or frequency difference. It is widely used in a variety of complex working conditions, harsh environments, liquid and solid material level measurement, especially in the dusty, heavy vapour, noise and so on. Radar level meter is a primary instrument or secondary instrument? The answer is very clear: radar level meter belongs to the primary instrument.

　　The reasons are as follows: Direct detection: radar level meter is directly installed on the storage vessel or pipeline, directly measuring the level height of the material, in line with the definition of primary instrumentation. No need for external signals: the radar level meter does not need to obtain signals from other instruments, it has its own function of transmitting and receiving microwaves, and can complete the level detection independently. Output Signal: The radar level meter usually converts the detected level information into an electrical signal (e.g. 4-20mA current signal), which is output to the downstream secondary instrument or control system for further processing and control.

　　Field applications: In practice, radar level meters are usually used as field level devices to directly face the various challenges in the industrial field, which is a typical characteristic of primary instruments. Although the radar level meter belongs to the primary instrument, it is very common to use it in conjunction with secondary instruments. For example, the radar level meter can transmit the measured level information to secondary instruments - such as PLC systems, DCS systems or other control devices - which will display, record or control actions according to the data provided by the radar level meter according to the set These secondary instruments will display, record or control the data provided by the radar level meter according to the set logic. This partnership makes the entire measurement and control process more accurate and efficient.

　　Summary: Radar level meter is a typical primary instrument, which is directly involved in the detection of the level and convert the measurement results into signals that can be processed by secondary instruments. Understanding this is essential for the correct selection and use of instrumentation to ensure the smooth operation of industrial automation systems. We hope that this article can help you to dispel your doubts about the classification of radar level meters, so that you can be confident in the face of such problems.