IEC TS 63064:2018 gives guidance and basic principles on how to design graphical symbols for diagrams for standardization and inclusion in IEC 60617. This document does not specify how to apply such graphical symbols in the diagrams.
IEC TS 63064:2018 pdf free download.The size is 1.7M.IEC TS 63064:2018,Graphical symbols for diagrams – Guidance on design for standardization in IEC 60617.
Graphical symbols for diagrams with the same visual impression representing different information should be avoided. Due to the limited number of graphical elements and the imited number of their combinations, different concepts may be assigned the same graphical identified by a separate identifier.
Graphical symbols for diagrams with different shapes should not represent the same concept.Depending on needs, different shapes may represent the same information such as in Form 1 Form 2, and so on. For a human reader, the meaning of a graphical symbol for diagrams can normally be recognized because of the context of the diagram. If not, such graphical symbols for diagrams shall be provided with supplementary information in the diagram.
4.4 Qualifying symbols
Qualifying symbols representing physical quantities shall be exclusively taken from the letter symbols as specified in IEC 80000 (all parts)， ISO 80000(all parts) and IEC 60027(all parts).
5 Grids and module
5.1 Orthogonal grid system
As a basis for the design of a graphical symbol for diagrams, an orthogonal grid system of parallel lines spaced 1 M apart, where M is the module, shall be used. See Annex A.
For the detailed design of graphical symbols for diagrams, 1 M is subdivided into 0,5 M. See also Annex A and SO 81714-1: 2010, Figure 9.
For the purpose of inclusion of graphical symbols in EC 60617 the size of module M=2,5 mm is defined.