What this shows me, to work safely with customers or contractors digrams, requires the diagrams to include a key.

Mike

Chris Pearson said:

If the cup is facing the wall, the symbol looks more like a plug with a stump of flex.

Just some context, this is schematically how a "plug contact" (bottom) in a "socket receptacle" (top) ought to be shown (ISO 7000 - 0354)

mapj1 said:

requires the diagrams to include a key

Not required for the symbols that conform to the standards, though, only for symbols not conforming ? Or at least that's the idea.

Not just being awkward, I've worked with schematics that would require sheets for the key alone, and to keep referring back isn't productive.

Same with colour code that's been harmonized for a very long time now - why do people invent their own?

probably in some cases because the standard is not readily available - see  that thread about free standards, and in the case of colour codes, has to suit the cable you can actually get- which in defence electronics at least  tends to be dominated by AWG sizes and US color codes. (red and black for DC +/- anyone ?

And for things like logic symbols, because the BS ones are rubbish.

M.

mapj1 said:

probably in some cases because the standard is not readily available - see  that thread about free standards,

But we have been talking about an isolator symbol, which is shown in BS 7671 itself, and also in IET Guidance, so it's really not "hidden away" anywhere?

Whilst it doesn't cover all the ISO 60617 symbols (the annual subscription for that being in the region of £600). most of the common ones can be found in the on-line browsing platform, e.g. for the symbols we are looking at, follow the link, click the radio button for "graphical symbols" and search for "disconnector"

mapj1 said:

and in the case of colour codes, has to suit the cable you can actually get

What I mean by colour codes, is the 2-letter colour code (4-letter for bi-coloured insulation) for wiring diagrams (say I have a 20-core cable that I want to connect for controls - you're not limited by colour except that GNYE is reserved for PE/PB (or combined PE+FE/PB+FB) and blue ought, as far as possible, to be used to refer to neutral (as defined in Part 2 of BS 7671).

Following the lead of BS EN IEC 60445, We've put the BS EN IEC 60757 colour codes in Table 51.1 of BS 7671 now, so there really is no excuse regarding access to the standard when preparing diagrams:

BK - Black
BN - Brown
RD - Red
OG - Orange
YE - Yellow
GN - Green
BU - Blue
VT - Violet
GY - Grey
WH - White

GNYE - Green-and-yellow

mapj1 said:

And for things like logic symbols, because the BS ones are rubbish.

Only because they are never taught. Just like most people would gravitate towards 'V=IR' rather than 'U=IR', and 'live and neutral' rather than 'line and neutral'

Sometimes the ANSI "NAND" or "AND" symbols end up being used for socket-outlets on architectural layout drawings/floor plans.

It's a TP isolator. The Architectural ACAD symbol. If you zoom in on the schematic you can see the handle at the top ; the three diagonal bars donate three phases 

regards burn 

burn said:

The Architectural ACAD symbol.

I'm not 100 % sure of the alignment with IEC 60617?

The OP says it's on a schematic, and the later post is a schematic ... therefore I believe symbols should be as per IEC 60617-7-13-xx and be like the single-line diagram symbols I posted earlier (with "TPN" qualifier or similar)?

However, if it's architectural (i.e. for use on floor plans and elevations to show rough location of equipment and controls in a room), IEC 60617-11-14-xx and a TNP (4-pole) switch, disconnector or isolator would look something like this, perhaps with a feature indicating it's an isolator.

Can anyone confirm who has access to the current IEC 60617 database?

I didn't say it was in line with IEC 60617. Nowadays most of us working on larger scale construction projects have no choice but to use Autodesk products (ACAD 2D or Revit for BIM 3D modelling) and have to take what they give us. 

regards burn

The great thing about standards is that there are so many of them to choose from!

Simon Barker said:

The great thing about standards is that there are so many of them to choose from!

Not in this case. BS 7671 specifically requires IEC 60617 (see Regulation 514.9.1)