Intereesting question - the "right symbol".


BS 7671 (as with the harmonised and international standards it's currently aligned with, HD60364-series and IEC 60364-series) require IEC60617 symbols on diagrams for electrical installations.


If we have safety-related systems, or electrical installations where isolation is required, and there's some confusion by operating and maintenance engineers about a particular symbol, then the results could be catastrophic. Worse, some organisations have their own standards, which may not align with the BS, EU or international standards ... a new member of staff, or a supplier or designer for a modification or extension to the installation or system may well have a problem reading the diagrams properly.


So, standardisation of symbols for diagrams really is a safety requirement for many installations.



However, I'm sure we've all been involved in large projects where the CAD standard for the project doesn't fully comply - with either the standards or the O&M organisation's own standard !!


There's another topic for discussion here - the use of the socket outlet symbols. Has anyone else noticed that they are always used tincorrectly on archtectural plan drawings (if you think how it appears in a circuit diagram, as a receptacle, you'll see it's not really acceptable to make it an "ANSI NAND Gate", and the open part of the box or "cup" should point away from the wall) ... so much for a standard !!

Intereesting question - the "right symbol".


BS 7671 (as with the harmonised and international standards it's currently aligned with, HD60364-series and IEC 60364-series) require IEC60617 symbols on diagrams for electrical installations.


If we have safety-related systems, or electrical installations where isolation is required, and there's some confusion by operating and maintenance engineers about a particular symbol, then the results could be catastrophic. Worse, some organisations have their own standards, which may not align with the BS, EU or international standards ... a new member of staff, or a supplier or designer for a modification or extension to the installation or system may well have a problem reading the diagrams properly.


So, standardisation of symbols for diagrams really is a safety requirement for many installations.



However, I'm sure we've all been involved in large projects where the CAD standard for the project doesn't fully comply - with either the standards or the O&M organisation's own standard !!


There's another topic for discussion here - the use of the socket outlet symbols. Has anyone else noticed that they are always used tincorrectly on archtectural plan drawings (if you think how it appears in a circuit diagram, as a receptacle, you'll see it's not really acceptable to make it an "ANSI NAND Gate", and the open part of the box or "cup" should point away from the wall) ... so much for a standard !!