Principal Details of Design Drafting for Substations by Computer

The Bonneville Power Administration has been developing a system for producing substation design drawings by using automatic data processing methods. Although the system is not yet 100-percent operational on all phases of substation design, it is operational on 115-kV one-line diagrams, buslayouts for 500-kV breaker- and-a-half and ring-bus schemes, 115-kV customer\´s service stations, and some switchboard and relay panels. The basic programming structure has been established, and the system offers a practical and economical method of decreasing the man-hour requirements for substation design, where repetitive-type drawingsmust be produced for construction purposes. The project has been separated into six basic parts: 1) developing the basic logical structure, 2) reducing the graphical components to numerical data, 3) retrieving and assembling the necessary components for a specific drawing, 4) transforming the numerical data back into graphic form ( plotting), 5) generating a "bill of material," 6) writing a "material summary list." Ways of applying these parts to design drafting are discussed.