Windy Miller wrote:
We're looking at a new dual fuel cooker. There's no dedicated cooker
supply in our kitchen so it has to go on the kitchen ring, either on a
FCU or a plug. The kettle is the only other high power device on the ring.

One Zanussi model has a power rating ('total rating' in their language)
of 3100W at 230V. Is this just over the limit or can this be connected
to our ring main?

One Zanussi model has a power rating ('total rating' in their language)
of 3100W at 230V. Is this just over the limit or can this be connected
to our ring main?

If it comes with a plug (or says that a 13A plug is acceptable in the
instructions), then it can be put on your ring, assuming you are correct
about the current appliance loading on the ring.

Christian.

Christian McArdle wrote:
One Zanussi model has a power rating ('total rating' in their language)
of 3100W at 230V. Is this just over the limit or can this be connected
to our ring main?

If it comes with a plug (or says that a 13A plug is acceptable in the
instructions), then it can be put on your ring, assuming you are correct
about the current appliance loading on the ring.

Thanks.

The plug bit I understand?

If it doesn't come with plug, can it be connected to a FCU off the ring
main through an appliance connector? At what power rating would I
expect to have to have a dedicated cooker circuit?

I can get no other information other than the 3100W figure for now.
That's a tad over 13A @230V, so it seems 'close'.

If it doesn't come with plug, can it be connected to a FCU off the ring
main through an appliance connector?

Not usually. If it is suitable for connection to a socket, EU law states it
should be supplied with a plug. Only appliances that could be supplied with
a plug are suitable for an FCU. Therefore, it is a reasonable assumption
that no plug supplied means no ring suitability. This presumption appears
correct in this case as the load is actually fractionally over 13A. If it
was 3100W/240V rated, I would say that it probably was suitable, as that
would be fractionally under 13A at both 230V and 240V.

At what power rating would I expect to have to have a dedicated cooker
circuit?

I would run the circuit using 6mm cable, but connect it to a 16A MCB. The
3100W/230V appliance needs a 16A MCB, but if you are running a cooker
circuit, make it 6mm so that it could be upgraded to a 32A cooker circuit in
case some muppet wants an electric cooker in the future.

Christian.

urchaidh wrote:
Windy Miller wrote:

We're looking at a new dual fuel cooker. There's no dedicated cooker
supply in our kitchen so it has to go on the kitchen ring, either on a
FCU or a plug. The kettle is the only other high power device on the ring.

One Zanussi model has a power rating ('total rating' in their language)
of 3100W at 230V. Is this just over the limit or can this be connected
to our ring main?

Did you forget to reply?


--
Alex Meaden
Technical Support Officer
Computing Service
University of Kent

On 8 Nov 2005 02:41:48 -0800, "urchaidh" wrote:

| Windy Miller wrote:
| We're looking at a new dual fuel cooker. There's no dedicated cooker
| supply in our kitchen so it has to go on the kitchen ring, either on a
| FCU or a plug. The kettle is the only other high power device on the ring.
|
| One Zanussi model has a power rating ('total rating' in their language)
| of 3100W at 230V. Is this just over the limit or can this be connected
| to our ring main?

The *actual* voltage in the UK is still 240V so 3100W / 240V is 12.91 amps
so it is OK. If you run it on the rated voltage of 230V it will take
slightly less current than that.

I have run 3100W kettles on our ring main for years without problems, and
the come with 13 amp plugs attached.
--
Dave Fawthrop dave hyphenologist co uk
Help make Usenet a better place: English is read downwards,
please don't top post. Trim replies to quote only relevant text.
Check groups.google.com before asking an obvious question.

Dave Fawthrop wrote:
On 8 Nov 2005 02:41:48 -0800, "urchaidh" wrote:

| Windy Miller wrote:
| We're looking at a new dual fuel cooker. There's no dedicated cooker
| supply in our kitchen so it has to go on the kitchen ring, either on a
| FCU or a plug. The kettle is the only other high power device on the ring.
|
| One Zanussi model has a power rating ('total rating' in their language)
| of 3100W at 230V. Is this just over the limit or can this be connected
| to our ring main?

The *actual* voltage in the UK is still 240V so 3100W / 240V is 12.91 amps
so it is OK. If you run it on the rated voltage of 230V it will take
slightly less current than that.

The *actual* appliance rating in this case is 3100W/230V which is over
13A. Increased the voltage to 240V and the current goes over 14A and
power to 3375W.

MBQ

In an earlier contribution to this discussion,
Dave Fawthrop wrote:


The *actual* voltage in the UK is still 240V so 3100W / 240V is 12.91
amps so it is OK. If you run it on the rated voltage of 230V it
will take slightly less current than that.

But if it's rated at 3100W at *230V* like the OP says, it will actually be
3375W at 240V, and take 14 amps. Even at 3100/230 it uses more than 13 amps.

Whilst it may physically work without blowing fuses, it is very marginal and
potentially dangerous - and cannot be recommeded. As others have said, if it
is capable of running off a 13A plug, it would have been supplied with one
fitted.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

wrote:
Dave Fawthrop wrote:
On 8 Nov 2005 02:41:48 -0800, "urchaidh" wrote:

| Windy Miller wrote:
| We're looking at a new dual fuel cooker. There's no dedicated cooker
| supply in our kitchen so it has to go on the kitchen ring, either on a
| FCU or a plug. The kettle is the only other high power device on the ring.
|
| One Zanussi model has a power rating ('total rating' in their language)
| of 3100W at 230V. Is this just over the limit or can this be connected
| to our ring main?

The *actual* voltage in the UK is still 240V so 3100W / 240V is 12.91 amps
so it is OK. If you run it on the rated voltage of 230V it will take
slightly less current than that.

The *actual* appliance rating in this case is 3100W/230V which is over
13A. Increased the voltage to 240V and the current goes over 14A and
power to 3375W.

MBQ

No. If its marked 13A @ 230v then its really 13A @240v, depsite how odd
that sounds. 230v is the legally accepted official description of our
really 240v supply. If it says 13A, its 13A.

Can you put a 13A cooker on a ring main? Of course. Can you put a 15A
cooker on a ring main? Of course. But possibly not at the same time as
a 200A arc welder.


NT

On 8 Nov 2005 04:56:56 -0800, wrote:

|
| Dave Fawthrop wrote:
| On 8 Nov 2005 02:41:48 -0800, "urchaidh" wrote:
|
| | Windy Miller wrote:
| | We're looking at a new dual fuel cooker. There's no dedicated cooker
| | supply in our kitchen so it has to go on the kitchen ring, either on a
| | FCU or a plug. The kettle is the only other high power device on the ring.
| |
| | One Zanussi model has a power rating ('total rating' in their language)
| | of 3100W at 230V. Is this just over the limit or can this be connected
| | to our ring main?
|
| The *actual* voltage in the UK is still 240V so 3100W / 240V is 12.91 amps
| so it is OK. If you run it on the rated voltage of 230V it will take
| slightly less current than that.
|
| The *actual* appliance rating in this case is 3100W/230V which is over
| 13A. Increased the voltage to 240V and the current goes over 14A and
| power to 3375W.

The 230V rating in the UK is just because of the EU rules. :-(

You snipped my experience of using a 3.1kw kettle for years without
problems, so I have repeated it.
--
Dave Fawthrop dave hyphenologist co uk
Help make Usenet a better place: English is read downwards,
please don't top post. Trim replies to quote only relevant text.
Check groups.google.com before asking an obvious question.

On Tue, 8 Nov 2005 12:57:03 -0000, "Set Square" wrote:

| In an earlier contribution to this discussion,
| Dave Fawthrop wrote:
|
|
| The *actual* voltage in the UK is still 240V so 3100W / 240V is 12.91
| amps so it is OK. If you run it on the rated voltage of 230V it
| will take slightly less current than that.
|
| But if it's rated at 3100W at *230V* like the OP says, it will actually be
| 3375W at 240V, and take 14 amps. Even at 3100/230 it uses more than 13 amps.
|
| Whilst it may physically work without blowing fuses, it is very marginal and
| potentially dangerous - and cannot be recommeded. As others have said, if it
| is capable of running off a 13A plug, it would have been supplied with one
| fitted.

My 3.1kw kettles come with a plug.
--
Dave Fawthrop dave hyphenologist co uk
Help make Usenet a better place: English is read downwards,
please don't top post. Trim replies to quote only relevant text.
Check groups.google.com before asking an obvious question.

No. If its marked 13A @ 230v then its really 13A @240v, depsite how odd
that sounds. 230v is the legally accepted official description of our
really 240v supply. If it says 13A, its 13A.

No. If it is marked as 13A @ 230V, it means just that. The same appliance
would draw 13.6A at 240V.

Many larger heating appliances, such as electric showers show a 230V rating
and a 240V rating. They will be different.

Christian.

My 3.1kw kettles come with a plug.

Yes. And a 3100W at 240V would be allowed to do this. It is a 3100W/230V
appliance that could not.

A 3100W/240V would draw 12.91A at 240V and would draw 12.4A at 230V.

Whilst a 3100W/230V appliance at 240V drawing 13.5 would actually be safe
enough in practice, it is not permitted to design a system with a built in
overload.

Christian.

In article , Dave
Fawthrop writes
On Tue, 8 Nov 2005 12:57:03 -0000, "Set Square" wrote:

| In an earlier contribution to this discussion,
| Dave Fawthrop wrote:
|
|
| The *actual* voltage in the UK is still 240V so 3100W / 240V is 12.91
| amps so it is OK. If you run it on the rated voltage of 230V it
| will take slightly less current than that.
|
| But if it's rated at 3100W at *230V* like the OP says, it will actually be
| 3375W at 240V, and take 14 amps. Even at 3100/230 it uses more than 13 amps.
|
| Whilst it may physically work without blowing fuses, it is very marginal and
| potentially dangerous - and cannot be recommeded. As others have said, if it
| is capable of running off a 13A plug, it would have been supplied with one
| fitted.

My 3.1kw kettles come with a plug.

A kettle is a short duty cycle item but a cooker is not, that makes quite a
difference.
--
fred
Plusnet - I hope you like vanilla

Dave Fawthrop wrote:
On 8 Nov 2005 04:56:56 -0800, wrote:

|
| Dave Fawthrop wrote:
| On 8 Nov 2005 02:41:48 -0800, "urchaidh" wrote:
|
| | Windy Miller wrote:
| | We're looking at a new dual fuel cooker. There's no dedicated cooker
| | supply in our kitchen so it has to go on the kitchen ring, either on a
| | FCU or a plug. The kettle is the only other high power device on the ring.
| |
| | One Zanussi model has a power rating ('total rating' in their language)
| | of 3100W at 230V. Is this just over the limit or can this be connected
| | to our ring main?
|
| The *actual* voltage in the UK is still 240V so 3100W / 240V is 12.91 amps
| so it is OK. If you run it on the rated voltage of 230V it will take
| slightly less current than that.
|
| The *actual* appliance rating in this case is 3100W/230V which is over
| 13A. Increased the voltage to 240V and the current goes over 14A and
| power to 3375W.

The 230V rating in the UK is just because of the EU rules. :-(

No, the 230V rating is a 230V rating. At 240V the power consumption
will be higher.

Look up the specs of a few high power items such as showers (e.g. MIRA
website is easy to use) or hobs where you'll find different values or a
range of values quoted for voltage v power.

MBQ

In article ,
Christian McArdle writes
No. If its marked 13A @ 230v then its really 13A @240v, depsite how odd
that sounds. 230v is the legally accepted official description of our
really 240v supply. If it says 13A, its 13A.

No. If it is marked as 13A @ 230V, it means just that. The same appliance
would draw 13.6A at 240V.

V**2 mate so 14.1A for a heating appliance.
--
fred
Plusnet - I hope you like vanilla

On Tue, 8 Nov 2005 16:51:26 UTC, fred wrote:

In article ,
Christian McArdle writes
No. If its marked 13A @ 230v then its really 13A @240v, depsite how odd
that sounds. 230v is the legally accepted official description of our
really 240v supply. If it says 13A, its 13A.

No. If it is marked as 13A @ 230V, it means just that. The same appliance
would draw 13.6A at 240V.

V**2 mate so 14.1A for a heating appliance.

pedant
But R will probably increase with the higher temperature from the higher
current, so it might not grow quite that much!
/pedant
--
The information contained in this post is copyright the
poster, and specifically may not be published in, or used by
Avenue Supplies, http://avenuesupplies.co.uk

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. For a long time it has been recommended that
special consideration is given to such heaters and a dedicated
circuit is strongly advised.

While an oven (I assume electric oven(s) and gas hobs in the cooker)
is unlikely to take as long to warm up, it still has a duty cycle
more onerous than a kettle has. If it really isn't possible to
provide a dedicated circuit then connecting it to a ring circuit
needs care and a thorough understanding of what one is doing.
Someone who asks the question may well not have enough
understanding.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

No. If it is marked as 13A @ 230V, it means just that. The same appliance
would draw 13.6A at 240V.

V**2 mate so 14.1A for a heating appliance.

V**2 for the power, not the current, assuming constant resistance.

i.e.

230V/13A = 17.69 ohms (and 2990W)

240V @ 17.69 ohms = 13.56A. (and 3256W)

Christian.

No, the 230V rating is a 230V rating. At 240V the power consumption
will be higher.

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
No. If it is marked as 13A @ 230V, it means just that. The same appliance
would draw 13.6A at 240V.

V**2 mate so 14.1A for a heating appliance.

V**2 for the power, not the current, assuming constant resistance.

i.e.

230V/13A = 17.69 ohms (and 2990W)

240V @ 17.69 ohms = 13.56A. (and 3256W)

Indeed, my bad, 14.1A was the answer for the for the o/ps wattage (not
that that's an excuse ;-)
--
fred
Plusnet - I hope you like vanilla

In article , Bob
Eager writes
On Tue, 8 Nov 2005 16:51:26 UTC, fred wrote:

In article ,
Christian McArdle writes
No. If its marked 13A @ 230v then its really 13A @240v, depsite how odd
that sounds. 230v is the legally accepted official description of our
really 240v supply. If it says 13A, its 13A.

No. If it is marked as 13A @ 230V, it means just that. The same appliance
would draw 13.6A at 240V.

V**2 mate so 14.1A for a heating appliance.

pedant
Sort yourself out mate ;-P
--
fred
Plusnet - I hope you like vanilla

On Tue, 08 Nov 2005 17:21:49 +0000, David Hansen
wrote:

| 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?
--
Dave Fawthrop dave hyphenologist co uk
Help make Usenet a better place: English is read downwards,
please don't top post. Trim replies to quote only relevant text.
Check groups.google.com before asking an obvious question.

Set Square wrote:
In an earlier contribution to this discussion,
Dave Fawthrop wrote:


The *actual* voltage in the UK is still 240V so 3100W / 240V is 12.91
amps so it is OK. If you run it on the rated voltage of 230V it
will take slightly less current than that.

But if it's rated at 3100W at *230V* like the OP says, it will actually be
3375W at 240V, and take 14 amps.

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.


Even at 3100/230 it uses more than 13 amps.

Whilst it may physically work without blowing fuses, it is very marginal and
potentially dangerous - and cannot be recommeded. As others have said, if it
is capable of running off a 13A plug, it would have been supplied with one
fitted.

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

wrote:
Set Square wrote:
In an earlier contribution to this discussion,
Dave Fawthrop wrote:


The *actual* voltage in the UK is still 240V so 3100W / 240V is 12.91
amps so it is OK. If you run it on the rated voltage of 230V it
will take slightly less current than that.

But if it's rated at 3100W at *230V* like the OP says, it will actually be
3375W at 240V, and take 14 amps.

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.

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

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.

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.

Christian McArdle wrote:
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.

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 perverted by newspeak.

NT

Christian McArdle wrote:
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.

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

David Hansen wrote:
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?

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.


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.

It can. I'm not endorsing it, but it can.

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).

yes it is, its designed to power 13A continuous appliances, such as fan
heaters etc.

The result can be at best overheating
and at worst a fire.

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.


For a long time it has been recommended that
special consideration is given to such heaters and a dedicated
circuit is strongly advised.

While an oven (I assume electric oven(s) and gas hobs in the cooker)
is unlikely to take as long to warm up, it still has a duty cycle
more onerous than a kettle has. If it really isn't possible to
provide a dedicated circuit then connecting it to a ring circuit
needs care and a thorough understanding of what one is doing.
Someone who asks the question may well not have enough
understanding.

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

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 perverted by newspeak.

They are exactly what they say. If the W/A rating is given at a particular
voltage, then you must assume that is what they meant.

We now have nominal 230V systems and are required to design systems for this
voltage. However, an appliance rating 3100W at 230V draws more than 13A even
at 230V, so is not permitted on a plug.

An existing 3100W appliance when things were officially 240V would now be
marked 2850W and be permitted, as it draw less than 13A.

Christian.

On 9 Nov 2005 07:18:14 -0800 someone who may be
wrote this:-

My 3kW fan heater came with a plug. Its long gone, but worked fine all
day long.

It wasn't fitted with a thermostat? Fascinating.

My 3.5kw toaster did too, and that was ok.

You had your 3.5kW toaster on all day long? Fascinating.

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.

It can. I'm not endorsing it, but it can.

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.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

David Hansen wrote:
On 9 Nov 2005 07:18:14 -0800 someone who may be
wrote this:-


My 3kW fan heater came with a plug. Its long gone, but worked fine all
day long.


It wasn't fitted with a thermostat? Fascinating.


My 3.5kw toaster did too, and that was ok.


You had your 3.5kW toaster on all day long? Fascinating.

The man likes toast, what more can I say?

In article ,
David Hansen wrote:
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.

An FCU has a plug in fuse unit. Describe how this will handle 13 amps long
term better than a plug and socket?

--
*What am I? Flypaper for freaks!?

Dave Plowman London SW
To e-mail, change noise into sound.

Meanwhile, (fused) connection units, or switches, provide a
rather means of connecting immersion heaters to fixed wiring
with less risk.

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.

David Hansen wrote:
On 9 Nov 2005 07:18:14 -0800 someone who may be
wrote this:-

My 3kW fan heater came with a plug. Its long gone, but worked fine all
day long.

It wasn't fitted with a thermostat? Fascinating.

It had an overheat stat which never tripped. Older fan heaters were not
normally thermostatic.


My 3.5kw toaster did too, and that was ok.

You had your 3.5kW toaster on all day long? Fascinating.

I'm sure you will have folloowed the point that a 13A plug can handle
13A continuous or 13A intermittent.


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.

It can. I'm not endorsing it, but it can.

Feel free to advocate this if you like.

I didnt, I merely stated a fact, that it can. One has to start by
getting the facts right, else what follows is valueless.

You will need to defend
yourself in court if it results in a fire.

Nope, there is no legal comeback for free advice on newsgroups.


Meanwhile, (fused)
connection units, or switches, provide a rather means of connecting
immersion heaters to fixed wiring with less risk.

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:-

An FCU has a plug in fuse unit.

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.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

In article ,
David Hansen wrote:
An FCU has a plug in fuse unit.

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?

I did wonder.

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).

You mentioned an FCU. Do you know what that means?

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.

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.

--
*What hair colour do they put on the driver's license of a bald man? *

Dave Plowman London SW
To e-mail, change noise into sound.

wrote:
Christian McArdle wrote:
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.

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 perverted by newspeak.

NT

So why do manufacturers give *different* ratings for 230V and 240V for
the *same* appliance? Which one are we supposed to use?

MBQ

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.

Christian.

On Thu, 10 Nov 2005 12:24:48 -0000, "Christian McArdle"
wrote:

| 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.
--
Dave Fawthrop dave hyphenologist co uk
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