Wiring Diagram Symbols

[JohnW2]

"Symbols for what" is what I'd ask, which particular items you want symbols for?

Indeed. Quite honestly, for the wiring/layout diagram, virtually anything would do - just squares/rectangles labelled 'switch', 'double socket', 'light' etc. would suffice!

For the schematic, there are very well-established symbols, which have changed little over the decades - and, again, he won't need many.

Kind Regards, John

 

[333rocky333]

I always read the Reg as, if you do use symbols then they have to be the proper ones, though there is no requirement to use symbols, a written schedule will do.
Up to the 17th the regs were saying use BS3939.
Some common symbols here
https://link.springer.com/content/pdf/bfm:978-1-349-81514-2/1.pdf

 

[JohnW2]

I always read the Reg as, if you do use symbols then they have to be the proper ones, though there is no requirement to use symbols, a written schedule will do. .... Up to the 17th the regs were saying use BS3939.

Interesting - I've never noticed that.

Some common symbols here ....

I may be wrong, but I suspect that a good few electricians would not recognise a good few of those BS3939 symbols.

I still stick with what I said before that, whatever BS7671 (to which there is no compulsion to work) says, pragmatically I think that the only really important thing is that the documentation should be easily understandable by anyone (particularly any electrician) who looks at it in the future. As I said, if there is any doubt that a particular symbol will be understood by every electrician who looks at it, it should be defined within the document - and, having looked at your link, I think that probably should include a good few (if not most!) of the BS3939 symbols (if they are used)!

Kind Regards, John

 

[ban-all-sheds]

My LABC asked me for detailed plans of layout and even cable routes before they would consider my application.

Were it not for the inadvisablity of p****ng them off, the correct response to that would be to refuse. It's a totally ridiculous and pointless requirement. There are no regulations which dictate where accessories must be placed, and as for routes, "I plan to comply with BS 7671" fully covers it. If they do not require post facto documentation of what was done from a registered electrician then they do not require it in advance from an unregistered one.

They were just being awkward in the hope they would dissuade you from doing it.

 

[ban-all-sheds]

That does not require the symbols to be in accordance with any formal standard (which many/most electricians probably wouldn't be aware of, anyway)

I may be wrong, but I suspect that a good few electricians would not recognise a good few of those BS3939 symbols.

(and anyway, how many domestic electricians know the symbols)

 

[ban-all-sheds]

The symbols are not in the 4th edition of the Electricians Guide to the 17th Edition.

Mine's older than that.

It's the sort of book which, after you've bought it, you think "never going to buy an updated one".

I am 59 and in good health, but I am not arrogant enough to think that will always be so. The bungalow will still be in family ownership long after my brain has ceased to be reliable. I would like to make things easier, and safer for all who come after. In any event, it is good practice, and might even prevent a silly error on my part, to have drawings before construction.

This is an ordinary house, not a nuclear power station, or oil refinery.

By all means do it for your own satisfaction, but I'm confident in promising you that yours will be the only ordinary house in the country with such drawings. Are you going to have documented version control procedures in place to ensure that any future changes to the electrical installation will be reflected in the documentation, and that there will be no risks of people inadvertently using out-of-date versions? Incorrect plans are worse than no plans at all.

 

[mattylad]

I can assure you that the planning department and any future home owner would not know one end of those standards from the other.
As said, little boxes with 2 letter text in will suffice, a little list on the side of the drawing identifying what each one means is adequate.
This is more than sufficient.

 

[ban-all-sheds]

Or little boxes which look like sockets, switches, etc.

 

[333rocky333]

I think most electricians, cant speak for the new Domestic course ones, know just some of the basic symbols, like sockets, switches lighting point and what back then was the fusebox, i too think most would struggle with the others, without a schedule attached.

When Part p initially came out was there not two sections, one regarding drawings and info etc to maintain the installation, I assume thats defunct now, could the Labc be a bit out of date.

 

[ban-all-sheds]

 

[ncoups]

Are you after an application that can input them onto drawings or just want to know what the symbols are?

Do you know of a basic software that you can input symbols and lines onto drawings with?

 

[ban-all-sheds]

https://www.bing.com/search?q=free+electrical+cad+software

 

[ericmark]

Be it Visio, or Electronics workbench, or another software package, I use the symbols supplied with the package. If the socket looks like a US version, so what you know what it is.

I do see the point in using software to pre work out volt drop, but really living room north wall sockets to MCB 5 B32 is enough. OK spur best room north corner taken from socket bedroom east corner may help some time in the future. But really what one really needs is Y plan central heating junction box wiring, knowing 5 and 6 goes to thermostat would be really help full. But knowing the JB is in the airing cupboard, well that's the first place I would look.

Of course should you submit a detailed design which shows the route of the ring final which with all the dimensions shown would require 150 meters of cable which is on the drawing as 2.5 mm² leaves the LABC with the task of actually adding up all the dimensions given and rejecting the plan as it will not conform with permitted volt drop. So in real terms a detailed plan is a real problem for them, as then they have to actually do some work.

With detailed plans it causes more problems than it solves, I have been on the jobs where the plans show a panel which will clearly stop some one accessing a valve, I have pointed out error and been told, fit it, but only use enough bolts to hold it, and don't gland any cables, once the client sees it we will be told to move it and we will get extra money to move it.

If detailed plans show sockets at 200 mm above finished floor level, then no good the inspector saying should be at 450 mm as it has already been agreed at 200 mm. So inspectors in the main prefer as built plans after every thing is installed, then if they see something they don't like, they can object.

 

[mattylad]

Google sketch, Desgignspark, Eagle the list is endless.

There is even one called Automation40 that I have installed but not got my head around yet. It has lots in it for electrical schematics.