Shows which choices can be made where IEC 60617-12 and IEC 60617-13 provide alternative techniques for the construction of graphical symbols that represent binary logic and analogue functions. Helps to create symbols having as consistent as appearance as possible, not depending on the originator, while still accurately representing the function. Furthermore, it establishes additional conventions for cases not covered by the IEC 60617-12 and IEC 60617-13. Has the status of a technical report type 3