GB/T 18657.4-2002 (English Version) PDF

Standard No.: GB/T 18657.4-2002
Language: Chinese, Available in English version
Release Date: 2002
Published By: General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
Latest: GB/T 18657.4-2002

Scope: This standard is applicable to telecontrol equipment and systems with bit-serial data transmission for the monitoring and control of geographically widely distributed processes. This standard gives the rules for defining information elements, proposes a set of information elements, and especially proposes some commonly used digital and analog process variables in telecontrol systems. Chapter 4 presents methods for defining the grammatical rules that apply to specific information elements, including semantic statements. These methods are instructions for the functional interpretation of the defined information domain. Chapter 5 applies the presented methods to the basic data types defined in Chapter 4 and introduces specific subtypes of data. Chapter 6 presents a set of information elements commonly used in telecontrol systems. The applications indicated in these elements and recommendations are advisory only. The statement of information element definition shall be defined in the application protocol set. A single information element, a sequence or a combination of information elements can form an information body, which is described in GB/T 18657.3. The information body address and the information body structure specification identifier.

GB/T 18657.4-2002 history

2002 GB/T 18657.4-2002 Telecontrol equipment and systems Part 5: Transmission protocols Section 4: Definition and coding of application information elements