IEC 62828-4:20 20制定了测试工业过程和机械控制系统测量和控制系统中使用的液位变送器的具体程序。对于一般测试程序，应参考适用于所有类型变送器的IEC 62828-1:20 17。 在整个本文件中，术语“工业变送器”涵盖用于工业过程和机械的测量和控制系统中的所有类型的变送器。 本文件的要求适用于所有液位测量原理。 为了提高清晰度，针对两个主要原理给出了发射机的详细描述。

IEC 62828-4:2020 establishes specific procedures for testing level transmitters used in measuring and control systems for industrial process and machinery control systems. For general test procedures, reference is to be made to IEC 62828-1:2017, applicable to all types of transmitters.
Throughout this document, the term "industrial transmitters" covers all types of transmitters used in measuring and control systems for industrial processes and for machinery.
The requirements of this document are applicable to all level measurement principles.
Detailed description of transmitters is given for two main principles for improved clarity.