Also, the fact that the voltage will actually more likely be 240V or even
250V, and that a 230V/13A appliance will draw more than 13A in practice is already accounted for in the specifications of the flexes, fuses and appliances.Christian.
In article , Christian McArdle writes
Indeed, my bad, 14.1A was the answer for the for the o/ps wattage (not that that's an excuse ;-)
Sort yourself out mate ;-P
| On Tue, 08 Nov 2005 14:26:40 +0000 someone who may be Dave Fawthrop | wrote this:- | | >My 3.1kw kettles come with a plug. | | How long does it take to boil the kettle when it is full? How often | is it boiled in a day? | | A fairly common mistake in house wiring is to think that a 3kW | immersion heater can be plugged into a ring main using a plug and | socket. The plug in particular is not really designed to feed such a | load for long periods of time (even a short immersion heater may be | on continuously for the best part of an hour if the cylinder is cold | and the thermostat set high). The result can be at best overheating | and at worst a fire.
In which case the fault is in the plug and/or socket. Where in the specification does it say they are only rated for intermittent loads?
No, its rating will be 13A on our nominallly 230v supply thats really
240v. Ie it will in fact be 13A @ 240v. The 230v description is newspeak, the now accepted description for what is IRL 240v.Not necessarily.
Tell that to all the owners of 15A appliances running on 13A plugs. No, its not ideal, but is common. 13A on a 13A plug is a non problem. People love to make issues where none exist.
There are genuine safety problems in peoples houses, 13A loads on 13A plugs isnt one of them.
NT
Is that true ? I've been saying no to all sorts of odd jobs because of Part P, and $%*&&&* knows I could do with the money.
They have a new edition of the 'electricians guide to the 16th' in the library wih a secion on part P too if anyone's curious.
Alex
On 8 Nov 2005 16:40:30 -0800 someone who may be "Alex Bird" wrote this:-
That applies only in England and Wales. It is a faulty implementation of what has been the case in Scotland for a very long time, giving legal recognition to the Wiring Regulations.
The fiddle in the tolerances of the supply to make it posible to say we are on the same nominal voltage as Europe is irrelevant when the rating is given at a specific voltage. Otherwise, why do manufacturers of high power appliances like showers and hobs give *different* ratings for
230V and 240V operation?MBQ
You're completely missing the point.
A 3100W/230A resistive appliance is not officially suitable for a 13A plug. A 3100W/240V rated appliance is. Of course, the system should work anyway without any problems. However, it is not permitted for a competent person to design a system that intentionally with malice aforethought has a larger design current than the components used to assemble it.
Christian.
As was said before. Imho it is you missing the point that the ratings are not what they say. They certainly used to be, but not now they've been complicated by newspeak.
What the resistance tolerance of a typical 13A heater is I've no idea.
NT
My 3kW fan heater came with a plug. Its long gone, but worked fine all day long. My 3.5kw toaster did too, and that was ok. Plugs are rated at 13A, meaning 13A rms continuous, with safety margin.
It can. I'm not endorsing it, but it can.
yes it is, its designed to power 13A continuous appliances, such as fan heaters etc.
If the plug or socket is faulty, sure. And there are faulty plugs about. When putting a 13A load on a plug I always check the plug doesnt get hot. Excessive oxidation on the pins, misshapen fuse holders, slack socket spring strips and burnt switch contacts are all problems at times.
This kind of madness gets increasingly common in the design and testing of electrical wiring. It stems partly from the one sided legal position, where you can bull and steam the customer as much as you want without worrying about comeback, but if you fail to meet every specified substantial margin just once you can be royally roasted. While that much is quite understandable, unfortunately in time it leads to this kind of unchecked silliness. The other thing it stems from is lack of knowledge, so claims like 'you cant run a 13A load on a 13A plug on a 30A ring' often go unchallenged..
NT
On 9 Nov 2005 07:18:14 -0800 someone who may be snipped-for-privacy@care2.com wrote this:-
It wasn't fitted with a thermostat? Fascinating.
You had your 3.5kW toaster on all day long? Fascinating.
Feel free to advocate this if you like. You will need to defend yourself in court if it results in a fire. Meanwhile, (fused) connection units, or switches, provide a rather means of connecting immersion heaters to fixed wiring with less risk.
The man likes toast, what more can I say?
An FCU has a plug in fuse unit. Describe how this will handle 13 amps long term better than a plug and socket?
The problem with connecting immersions to a ring is that they use up lots of the current capability, making it likely to overload or trip. It is particularly likely in the case of a gas mains failure, where the same ring is likely to be running several electric space heaters, just when you need to turn your backup immersion on. The square metre limits on socket circuits are all about how much electricity the rooms will need to be heated in the event of main heating system failure.
The reason immersions should normally be plugged in is, therefore, nothing to do with the point of connection being a plug/socket. The 13A plug/socket is rated for continuous use, although you should always ensure that the plug and socket of any 13A appliance is in good condition before use, due to the potential for even a slight bad connection to have bad consequences.
Christian.
It had an overheat stat which never tripped. Older fan heaters were not normally thermostatic.
I'm sure you will have folloowed the point that a 13A plug can handle
13A continuous or >13A intermittent.I didnt, I merely stated a fact, that it can. One has to start by getting the facts right, else what follows is valueless.
Nope, there is no legal comeback for free advice on newsgroups.
Theyre rated the same 13A continuous.
NT
On Wed, 09 Nov 2005 17:10:47 +0000 (GMT) someone who may be "Dave Plowman (News)" wrote this:-
Now, there's a surprise:-) Did you really think that I was unaware that inside a fused connection unit there is a BS1362 fuse, the same thing that is inside a BS1363 plug?
Well, I was aware of that before you said so. In fact I was aware of it for several decades before you said so. It does not alter the argument, because it is not the fuse that overheats. There is also not a fuse in a connection unit, or a switch (without a fuse incorporated into the same unit).
Your loud assertions may convince some. However, I'll stick to the advice that John Whitfield gave in his guides to the 15th and 16th editions, which is that plugs and sockets are not a good way of connecting immersion heaters to fixed wiring.
I did wonder.
You mentioned an FCU. Do you know what that means?
Because the implication is it will be connected to a final ring main circuit.
Does he recommend using an FCU?
Most would wire an immersion on its own radial with a 16 amp MCB and a DP isolator - not an FCU in sight.
You should design for the 230V value. The 240V value is just used as an indication of the likely performance, as you are more likely to have 240V available rather than 230V, although you'd have to measure to be sure.
Christian.
| > So why do manufacturers give *different* ratings for 230V and 240V for | > the *same* appliance? Which one are we supposed to use? | | You should design for the 230V value. The 240V value is just used as an | indication of the likely performance, as you are more likely to have 240V | available rather than 230V, although you'd have to measure to be sure.
Anyone designing something for use in the UK has massive documentary evidence that it will be used at 240V, and rightly will design and rate for
240V. The 230V figure is only a political fudge to allow stuff designed in the EU to be sold here. If I were designing something in say France for use in the UK, I would design for 240V. I would have to put a 13 amp plug on the wire so it would have to have a different drawing, as any draughie knows because "Form fit or function is different. Any components, motors, heating elements, etc. used could also be slightly different, in the windings or resistance, the rest could be the same.It is commonplace to have slightly different designs for different markets. I once went for a job at a company making refrigerators. I was shown an absolutely foul gaudy fridge, with the explanation, "this is the French version" where the salesman throws open the door and says doesn't it look wonderful.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.