This Practice is a guideline for developing Overall Electrical One-Line Diagrams (OEOLDs) by engineers and designers. It covers the generation of new OEOLDs and may not apply to the revision of existing OEOLDs.
This Practice applies to one-line diagrams that fit the definition of an OEOLD in Section 3. This Practice uses ANSI/IEEE 315 - IEEE Graphic Symbols for Electrical and Electronics Diagrams and IEEE C57.12.80 - IEEE Standard Terminology for Power and Distribution Transformer symbols.
The main purpose of an OEOLD is to provide an initial view of the electrical system for use in early design discussions. Then, the OEOLD can be updated as the project develops and kept current to provide a reference document that shows a high level view of the overall electrical system.
As a secondary purpose and function the symbols provided for use in a OEOLD are intended to provide basic information. The basic information is shown in visible fields by default. Many OEOLD symbols have hidden or invisible fields that provide extra information or details. The invisible or hiddens fields can be changed to be visible based on owner requirements.
This Practice can be applied to CAD systems used for developing OEOLDs, and is not supplier, hardware, or software specific. Electronic native files for the text, symbols, and cover sheets are available from PIP for use in CAD systems and have been developed in AutoCAD 2015. While the symbols can also be developed in Microstation DGN files, the functionality from AutoCAD may not be available in Microstation. Development of project-specific legend sheets is recommended using the PIP native files as a starting point. Additions and/or deletions are permitted to meet project requirements. Drawing borders and title blocks can be altered to be project specific.
The guidelines in this Practice provide a balance between showing all data on OEOLDs and making OEOLDs legible and easy to read. Although this Practice describes major components in the electrical system, specific applications may require additional or alternative components. Determinations concerning fitness for purpose and matters of application of the Practice to a particular project or engineering situation should not be made solely on the information contained in this Practice.
The OEOLD symbols included in the Appendices of this Practice are not intended to recommend specific design details or requirements. An example OEOLD is included to provide an illustration of how the elements of this Practice are combined into an OEOLD.
