Load for a 5amp wall socket

[meow2222]

Britain's target voltage is 240v, not 230. So if you want the correct answers, it needs to be 240. We have an odd situations now where what is in actual fact 240v is described as 230v.

NT

[meow2222]

230v is not Britain's actual mains voltage, its a description of a standard within which our 240v supply falls (after we tweaked the outlying permitted limits).

NT

[charles]

It was 240v (+6%, -6%) until 31 December 1994. Since then it has been 230v (+10% - 6%). Permitted range: 216v -253v)

[Dave Plowman (News)]

He's wrong. They are common where you want to plug in say a table lamp to a lighting circuit switched from elsewhere, but prevent that being overloaded by other devices - as might happen if you used a 13 amps one. Especially where the lighting circuit has a dimmer.

[John Rumm]

Yup, I am sure most folks know that, but you should still design using the nominal voltage of 230V since this is what is used to generate all the tables of permitted circuit lengths etc as found in the OSG etc.

[meow2222]

Not quite, measure some socket voltages to see what it actually is.

NT

[ARW]

Are they f*ck - they are on a radial circuit:-)

If you ALWAYS use a fused plug then that would be OK.

[charles]

well yes, that the legal requirement.

[Graham.]

You may wish to comment on my switched socket in the dining room. It's a 2 gang 13A socket swiched by a 15A switch by the door. It's a spur off the downstairs ring protected by a 32A MCB.

Done when the property was rewired around 1972 by the previous owner who were, incidentally American. That switch was, and still is the only light-switch for that room, there were no fixed light fittings.

[ARW]

Indeed, and if the voltage is outside that range then the suppliers have to rectify it.

[meow2222]

Since the target voltage is 240, its in fact 240v +13 -24, not 230+- anything. 230 is the international standard, not the British voltage.

NT

[John Rumm]

Its not the British voltage delivery target which as you say remains at

240V, but it *is* the British standard (i.e. 230v +10%/-6%).

It also what we use as a basis for calculations.

[John Rumm]

In effect, no different from any other unfused spur then...

[meow2222]

Bit of a contradiction there.

NT

[ARW]

So why not call it 230v +23 -14? The voltages are anywhere between both ranges.

[meow2222]

For a descriptor such as a +-b, a is the target figure, b the tolerance limits. So our current supply voltage is 240 +13 -24 by basic definition. The term 230v is a fudged description rather than a real engineering description.

NT

[ARW]

Why do you not go and shove the target voltage up your arse? - preferably without RCD protection.

All UK calculations are done at 230V as that is the nominal voltage for the UK supply and for the appliances that use the supply. Apart from incandescent lamps and really old appliances it makes no difference.

[Dave Plowman (News)]

Bought some ex-BBC gear recently. Had a mains selector switch with (along with others) 230 and 240v. Had a Dymo label across the selector - 240v only. Later versions had no selector switch - you had to open it up and do a solder job to alter the tapping. ;-)

[meow2222]

This is getting stupid

[John Rumm]

Well you started it ;-)

(suggesting that my use of 230V in a calculation was inappropriate)