GB/T 4728.1-2005 in English

《GB/T 4728.1-2005电气简图用图形符号 第1部分:一般要求》由TC27（全国电气信息结构、文件编制和图形符号标准化技术委员会）归口，主管部门为国家标准化管理委员会
本部分为GB/T 4728的第1部分，等同采用IEC 60617 database《电气简图用图形符号数据库标准》(英文版)中的相应内容。 本部分代替GB/T 4728.1-1985《电气简图用图形符号 第1部分：一般 要求》。

1.1 Introduction
This standard database is one assemblage of data describing the graphic symbols and their attributes. Please point-and-click the "General Descriptions" at left to comprehend how the database is constituted, how to apply the graphic symbols and how to handle the change request of new symbols.
1.2 Languages
All the symbol data in the database are expressed in two languages: Chinese and English, users may open one kind of language to look through the symbol data.
1.3 Linkage
All the items shall be looked through in categories; the blue triangle arrowhead is applied to represent the linkage to other factors or to the compulsory exercise.
1.4 Symbol query
This database standard provides two kinds of symbol querying methods.
1.4.1 Query function
The asterisk (*) may be applied as the asterisk wildcard when querying in the specified language, and two query criterions will be connected with logical operator "AND" (AND gate) or "OR" (OR gate). The character fields may be used for query are: name, surname, keyword, SN of the previous edition (such as 03-01-15) and symbol identification number (such as S00823).
1.4.2 Look through by categories
The symbols are classified according to the identification number, keyword, application category, function category, shape category, condition and the standard number of previous edition. The specific projection list of this classification will appear by clicking the object classification, and then the web page will open by clicking the reference No.(blue ) of one item therein. Linkages to relevant symbols or application notes also may exist in this specific page.
1.5 Snapshot dump
The maintenance team of this database standard will carry out snapshot dump on the database contents periodically in format of PDF. Please click the "Snapshots" at left for further detailed information.
1.6 Consultation
Please contact the customer service center of the database standard if you have any problem on subscription (expiration and renew) or database contents.

Foreword I
1 Symbol Query
1.1 Introduction
1.2 Languages
1.3 Linkage
1.4 Symbol query
1.5 Snapshot dump
1.6 Consultation
2 General Descriptions
2.1 Database structure
2.2 How to apply the existing symbols
2.3 Selection of symbols
2.4 Symbol size
2.5 Orientation of symbols
2.6 Representation of terminals
2.7 How to combine new symbols into the existing symbols
2.8 How to handle "new symbol request"