本标准为显示所需布线系统各部分的一般物理位置和布置提供了依据，确定了在建筑物中提供电气安装所需的各类材料的物理要求。在某些情况下，符号可能表示系统的功能或电气特性；然而，这并不是他们的主要目的。按照美国国家标准Y32的规定，这些功能或特性通过使用电气图的图形符号来表示。2-1970，电气和电子图的图形符号（IEEE Std 315）- 1971). 图纸上通过使用各种适用的插座和设备符号，以及互连电路或馈线，并辅以必要的符号，显示了所需的安装。一般来说，基本符号已包含在符号一览表中。在某些情况下，可能需要使用在基本符号内或侧面绘制的字母表中的数字或字母，以识别符号在特定类型或插座用途中的具体应用。在某些情况下，符号标识的物品的物理或电气尺寸将标注在其一侧。

This standard provides a basis for Showing the general physical location and arrangement of the sections of the required wiring system Identifying the physical requirements for various types of materials needed to provide the electrical installation in buildings In some instances, the symbols may indicate the function or electrical characteristics of the system; however, that is not their primary purpose. Such functions or characteristics are shown by the use of the graphic symbols for electrical diagrams, as specified in American National Standard Y32.2-1970, Graphic Symbols for Electrical and Electronics Diagrams (IEEE Std 315-1971). The required installation is shown on the drawing by the use of the various applicable outlet and equipment symbols, together with interconnecting circuit or feeder run lines, supplemented with necessary notations. In general, basic symbols have been included in the symbol schedule. In some instances, the use of numbers or letters of the alphabet drawn in, or at the side of, the basic symbol to identify a specific application of the symbol for a particular type or use of outlet may be required. In some instances, the physical or electrical size of the item identified by the symbol will be noted to one side of it.