Installing oven

[GB]

I've just installed a single oven. The previous one had a 13 amp plug,
so I simply wired up the new oven the same way. It's a single oven, with
"Energy consumption 0.79 kWh", which doesn't seem too high for a 13 amp
plug.

What concerned me is that the manual that came with it said it should be
wired to a DPDT switch, direct from the consumer unit, and fused with a
maximum of 30A. (**See below for verbatim wording.) That would mean
rewiring the kitchen and probably replacing the consumer board to
provide the extra connection. It seems overly specified, and I wondered
whether they cut and paste the same stuff into all their oven manuals,
whether they are low end single ovens or high end double ones?

It's this oven here.
http://www.currys.co.uk/gbuk/household-appliances/cooking/ovens/essentials-cbconx12-electric-oven-stainless-steel-12448421-pdt.html


Am I misunderstanding what's required? Does it really require a
dedicated cable? It would be pretty easy just to break into the ring
main and put in an oven connection with a DPDT switch.

Any help gratefully received.


**
"An approved suitable cable must be connected from the Consumer Unit
(main fuse box)and be protected by its
own 30 amp fuse or Micro Circuit Breaker (MCB).
The electrician must provide a fused double-pole isolation switch, which
disconnects both the line (live) and
neutral conductors, with a contact separation of at least 3 mm
incorporated into the fixed wiring. The fused
switch should be fitted to the kitchen wall, and must be placed in an
easy accessible position in accordance with
IEE regulations. Connect the fused switch to a junction box which should
be fitted on the wall. The ovens power
supply cable can then be connected. Connect one end to the junction box
and connect the other end to the
ovens power connection box which is located at the back of the oven.
Remove the cover of the power connection
box and install the cable, in accordance with the connection diagram.
The power supply cable must be positioned
away from direct heat sources. It should not be subjected to a
temperature rise of more than 50°C above room
temperature."

[ARW]

On 19/11/2016 21:09, GB wrote:
> I've just installed a single oven. The previous one had a 13 amp plug,
> so I simply wired up the new oven the same way. It's a single oven, with
> "Energy consumption 0.79 kWh", which doesn't seem too high for a 13 amp
> plug.

You might be at home to Mr Cockup on this one.

The 0.79 kWh is some sort of bollocks that that is used by the
manufacturer to represent the average use per cycle of the oven and has
fuck all to do with the maximum electrical load.




--
Adam

[Graham.]

It's a single oven, with
>"Energy consumption 0.79 kWh", which doesn't seem too high for a 13 amp
>plug.

A mobile phone charger will consume that much energy if you leave it
switched on for long enough.

It's the power consumption in Watts you need.




--

Graham.

%Profound_observation%

[tabb...@gmail.com]

There's no power rating in the specs so we can't know. Look on the oven's rating plate and tell us. If it is a 30A oven, just get a suitable 13A or less (3.1kW max) oven instead.


NT

[Graham.]

On Sat, 19 Nov 2016 21:09:12 +0000, GB <NOTso...@microsoft.com>
wrote:

http://manuall.co.uk/currys-essentials-cbconw12-oven/

10SpecificationsModelCBCONW12 / CBCONX12Rated Voltage230-240V
Rated Frequency50 Hz
Power2600-2800 W
Current11 – 12 A
Top Element1200 W
Bottom Element1100 W
Grill1400/2600 W
Net Weight30.2 kg
Product Dimensions59.5 (W) x 59 (H) x 57 (D) cm
Usable Oven Capacity61 Litres
Energy Efficiency ClassA


So as far as I can see you can use your existing circuit, but I
personally would replace the socket with an FCU and hardwire it in.

Lets see what Adam says.


--

Graham.

%Profound_observation%

[John Rumm]

On 19/11/2016 21:09, GB wrote:

> I've just installed a single oven. The previous one had a 13 amp plug,
> so I simply wired up the new oven the same way. It's a single oven, with
> "Energy consumption 0.79 kWh", which doesn't seem too high for a 13 amp
> plug.

Alas that does not tell you much of use directly, however the manual
seems to indicate that it can draw up to 2800W, which will be ok on a
plug (although would be better on a proper flex outlet).

> What concerned me is that the manual that came with it said it should be
> wired to a DPDT switch, direct from the consumer unit, and fused with a
> maximum of 30A. (**See below for verbatim wording.) That would mean

Note it says fused at a *maximum* of 30A - it does not specify the
actual required minimum.

They may be assuming you will be powering a hob from the same circuit.

(its also a bit daft since many cooker circuits will be protected by a
32A MCB)


--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

[Tim Watts]

From the manual:

http://ns323666.ip-37-187-156.eu/manuals/Currys%20Essentials%20Oven/Currys%20Essentials%20CBCONW12%20Oven.pdf

"Power 2600-2800 W"

So a 16A direct circuit would be satisfactory. Technically it *could* be
plugged in on a 13A plug but that would not be so recommended. Can't see
anything wrong with a 13A spur though, with DP isolator (ie switched
fused spur).

Especially as it will not draw that power level for long, once it's
heated up and cycling.

[tabb...@gmail.com]

On Saturday, 19 November 2016 22:09:33 UTC, Graham. wrote:
> On Sat, 19 Nov 2016 21:09:12 +0000, GB <NOTso...@microsoft.com>
> wrote:
>
> >I've just installed a single oven. The previous one had a 13 amp plug,
> >so I simply wired up the new oven the same way. It's a single oven, with
> >"Energy consumption 0.79 kWh", which doesn't seem too high for a 13 amp
> >plug.
> >
> >What concerned me is that the manual that came with it said it should be
> >wired to a DPDT switch, direct from the consumer unit, and fused with a
> >maximum of 30A. (**See below for verbatim wording.) That would mean
> >rewiring the kitchen and probably replacing the consumer board to
> >provide the extra connection. It seems overly specified, and I wondered
> >whether they cut and paste the same stuff into all their oven manuals,
> >whether they are low end single ovens or high end double ones?
> >
> >It's this oven here.
> >http://www.currys.co.uk/gbuk/household-appliances/cooking/ovens/essentials-cbconx12-electric-oven-stainless-steel-12448421-pdt.html

> http://manuall.co.uk/currys-essentials-cbconw12-oven/
>
> 10SpecificationsModelCBCONW12 / CBCONX12Rated Voltage230-240V
> Rated Frequency50 Hz
> Power2600-2800 W
> Current11 – 12 A
> Top Element1200 W
> Bottom Element1100 W
> Grill1400/2600 W
> Net Weight30.2 kg
> Product Dimensions59.5 (W) x 59 (H) x 57 (D) cm
> Usable Oven Capacity61 Litres
> Energy Efficiency ClassA
>
>
> So as far as I can see you can use your existing circuit, but I
> personally would replace the socket with an FCU and hardwire it in.
>
> Lets see what Adam says.

OK on a 13A plug then.


NT

[The Natural Philosopher]

On 20/11/16 02:46, tabb...@gmail.com wrote:
> On Saturday, 19 November 2016 22:09:33 UTC, Graham. wrote:
>> On Sat, 19 Nov 2016 21:09:12 +0000, GB <NOTso...@microsoft.com>
>> wrote:
>>
>>> I've just installed a single oven. The previous one had a 13 amp plug,
>>> so I simply wired up the new oven the same way. It's a single oven, with
>>> "Energy consumption 0.79 kWh", which doesn't seem too high for a 13 amp
>>> plug.

Irrelevant.

What counts is the peak power.

I.e. what happens when you switch on everything?

>>>
>>> What concerned me is that the manual that came with it said it should be
>>> wired to a DPDT switch, direct from the consumer unit, and fused with a
>>> maximum of 30A. (**See below for verbatim wording.) That would mean
>>> rewiring the kitchen and probably replacing the consumer board to
>>> provide the extra connection. It seems overly specified, and I wondered
>>> whether they cut and paste the same stuff into all their oven manuals,
>>> whether they are low end single ovens or high end double ones?
>>>
>>> It's this oven here.
>>> http://www.currys.co.uk/gbuk/household-appliances/cooking/ovens/essentials-cbconx12-electric-oven-stainless-steel-12448421-pdt.html
>
>> http://manuall.co.uk/currys-essentials-cbconw12-oven/
>>
>> 10SpecificationsModelCBCONW12 / CBCONX12Rated Voltage230-240V
>> Rated Frequency50 Hz
>> Power2600-2800 W
>> Current11 – 12 A
>> Top Element1200 W
>> Bottom Element1100 W
>> Grill1400/2600 W

The point here is whether or not all these can be put on together. If
they can they will blow 13A fuses.

>> Net Weight30.2 kg
>> Product Dimensions59.5 (W) x 59 (H) x 57 (D) cm
>> Usable Oven Capacity61 Litres
>> Energy Efficiency ClassA
>>
>>
>> So as far as I can see you can use your existing circuit, but I
>> personally would replace the socket with an FCU and hardwire it in.
>>
>> Lets see what Adam says.
>
> OK on a 13A plug then.
>

Only if it is not physically possivle to have grill top and bottom
elements all on at once.

>
> NT
>


--
If you tell a lie big enough and keep repeating it, people will
eventually come to believe it. The lie can be maintained only for such
time as the State can shield the people from the political, economic
and/or military consequences of the lie. It thus becomes vitally
important for the State to use all of its powers to repress dissent, for
the truth is the mortal enemy of the lie, and thus by extension, the
truth is the greatest enemy of the State.

Joseph Goebbels

[Harry Bloomfield]

Graham. submitted this idea :

> So as far as I can see you can use your existing circuit, but I
> personally would replace the socket with an FCU and hardwire it in.

A plug and socket provides a much safer/ more certain means of
isolation for servicing, than a DP switch. As it needs to draw close to
the maximum capability of a 13amp socket, both plug and socket need to
be good quality items.

[Mike Clarke]

On 19/11/2016 22:09, Graham. wrote:
> http://manuall.co.uk/currys-essentials-cbconw12-oven/
>
> 10SpecificationsModelCBCONW12 / CBCONX12Rated Voltage230-240V
> Rated Frequency50 Hz
> Power2600-2800 W
> Current11 – 12 A

The maximum current at 2800W would be 2800/240 = 11.67A which would be
OK on a 13A plug.

> Top Element 1200 W
> Bottom Element 1100 W
> Grill 1400/2600 W

Which makes 4900W maximum if everything was full on, drawing 20.4A.

But the guideline for diversity is to take the first 10A plus 30% of the
rest which gives 13.1A.

You'd get away with that on a 13A plug unless you have a lot of other
high powered things on the same ring circuit. But as said elsewhere,
make sure the plug and socket are decent quality.

--
Mike Clarke

[Mike Clarke]

On 19/11/2016 22:09, Graham. wrote this extract from the manual for an oven:

> "An approved suitable cable must be connected from the Consumer Unit
>>(main fuse box)and be protected by its
>>own 30 amp fuse or Micro Circuit Breaker (MCB).
>>The electrician must provide a fused double-pole isolation switch, which
>>disconnects both the line (live) and
>>neutral conductors, with a contact separation of at least 3 mm
>>incorporated into the fixed wiring.

Looks like a distinct lack of joined up thinking there. If the oven
really *needs* a 30A fused circuit then there's no need for a second 30A
fuse in the switch beside the oven. They don't say what rating the fused
switch should be but the only domestic fused double pole switch you're
likely to come across is a 13A FCU, implying that it should also be OK
on a 13A socket.

If you use a plug and socket instead of a FCU then it would be worth
using an *unswitched* socket. Not all switch sockets are double pole and
they might not provide a 3mm separation gap. Unplugging before working
on the oven will ensure total isolation.

The only reason I could see the need for a dedicated 30A supply would be
if you were running the oven and a hob off the same circuit. If you were
connecting the hob directly to the main cooker switch then you'd need to
use a heavy 30A cable from the main cooker switch unless you used a 13A FCU.

--
Mike Clarke

[GB]

On 20/11/2016 05:17, The Natural Philosopher wrote:

>>
>>> http://manuall.co.uk/currys-essentials-cbconw12-oven/
>>>
>>> 10SpecificationsModelCBCONW12 / CBCONX12Rated Voltage230-240V
>>> Rated Frequency50 Hz
>>> Power2600-2800 W
>>> Current11 – 12 A
>>> Top Element1200 W
>>> Bottom Element1100 W
>>> Grill1400/2600 W
>
> The point here is whether or not all these can be put on together. If
> they can they will blow 13A fuses.

I have checked the oven's function controller. Page 5 of the manual, if
interested.

It is possible to have top and bottom elements on together = 2300W
It is possible to have grill and top element on together. I assume the
grill is actually 1400W, and the higher figure shown of 2600W is the top
element and grill combined.

So, that's a maximum of 10.8A.

As far as isolation is concerned, it's only possible to disconnect the
plug once the oven has been removed from the kitchen unit. OTOH, it's
easy enough to switch the ring main off, or even the whole supply.
Exactly the same would apply to a FCU in the same location.

Thanks very much, everyone.

[tabb...@gmail.com]

13.1A for limited time would be ok on a plug. 20A would not. Try some plugs & see if you think otherwise.


NT

[Roger Hayter]

In practice the grill function and the oven function are likely to share
the same elements, so not simultaneously usable.

--

Roger Hayter

[DerbyBorn]

Surely the top element is the grill element.

Mine has a knob to select Oven or Grill.

[Mike Clarke]

On 20/11/2016 12:38, tabb...@gmail.com wrote:
> 13.1A for limited time would be ok on a plug. 20A would not. Try some plugs & see if you think otherwise.

But diversity considerations mean that it won't draw 20A for sufficient
time to be a problem.

--
Mike Clarke

[tabb...@gmail.com]

On Sunday, 20 November 2016 13:54:01 UTC, Mike Clarke wrote:

> On 20/11/2016 12:38, tabbypurr wrote:
> > 13.1A for limited time would be ok on a plug. 20A would not. Try some plugs & see if you think otherwise.
>
> But diversity considerations mean that it won't draw 20A for sufficient
> time to be a problem.

Try it or don't.

[John Rumm]

Ideally there should be a accessible isolation switch within 2m of the
cooking appliance that can be reached without moving the appliance. So a
cooker switch above the worktop or in an adjacent cupboard usually
suffices.

Note that switching off the circuit does not usually truly isolate it,
since the neutral will still be connected.

> Thanks very much, everyone.

[John Rumm]

On 20/11/2016 09:58, Mike Clarke wrote:
> On 19/11/2016 22:09, Graham. wrote:
>> http://manuall.co.uk/currys-essentials-cbconw12-oven/
>>
>> 10SpecificationsModelCBCONW12 / CBCONX12Rated Voltage230-240V
>> Rated Frequency50 Hz
>> Power2600-2800 W
>> Current11 – 12 A
>
> The maximum current at 2800W would be 2800/240 = 11.67A which would be
> OK on a 13A plug.

The range is probably a reflection of the 2800W figure only being
achievable with a true 240V...

>
>> Top Element 1200 W
>> Bottom Element 1100 W
>> Grill 1400/2600 W
>
> Which makes 4900W maximum if everything was full on, drawing 20.4A.

I would expect since they quote a power figure, that would be the actual
highest achievable (i.e. not all elements can be run at the same time
due to interlocks)

[ARW]

On 20/11/2016 17:00, John Rumm wrote:
> On 20/11/2016 09:58, Mike Clarke wrote:
>> On 19/11/2016 22:09, Graham. wrote:
>>> http://manuall.co.uk/currys-essentials-cbconw12-oven/
>>>
>>> 10SpecificationsModelCBCONW12 / CBCONX12Rated Voltage230-240V
>>> Rated Frequency50 Hz
>>> Power2600-2800 W
>>> Current11 – 12 A
>>
>> The maximum current at 2800W would be 2800/240 = 11.67A which would be
>> OK on a 13A plug.
>
> The range is probably a reflection of the 2800W figure only being
> achievable with a true 240V...
>
>>
>>> Top Element 1200 W
>>> Bottom Element 1100 W
>>> Grill 1400/2600 W
>>
>> Which makes 4900W maximum if everything was full on, drawing 20.4A.
>
> I would expect since they quote a power figure, that would be the actual
> highest achievable (i.e. not all elements can be run at the same time
> due to interlocks)

By interlock do you mean the switch on the front that only allows the
use of the grill and top oven element at the same time?:-)



--
Adam

[John Rumm]

Yup.

[Graham.]

On Sun, 20 Nov 2016 17:00:44 +0000, John Rumm
<see.my.s...@nowhere.null> wrote:

>On 20/11/2016 09:58, Mike Clarke wrote:
>> On 19/11/2016 22:09, Graham. wrote:
>>> http://manuall.co.uk/currys-essentials-cbconw12-oven/
>>>
>>> 10SpecificationsModelCBCONW12 / CBCONX12Rated Voltage230-240V
>>> Rated Frequency50 Hz
>>> Power2600-2800 W
>>> Current11 – 12 A
>>
>> The maximum current at 2800W would be 2800/240 = 11.67A which would be
>> OK on a 13A plug.
>
>The range is probably a reflection of the 2800W figure only being
>achievable with a true 240V...

I'm fed from an unusual looking transformer in a roadside cabinet and
I get a constant true 245V RMS


--

Graham.

%Profound_observation%

[John Rumm]

So you might get another 60W out of it ;-)

[Fredxxx]

I felt obliged to look on Screwfix to check, but irrespective of the
regulations surrounding cooker switches, all the ones I saw were DP
(dual/double pole) switching.

[John Rumm]

I was referring to switching off the *circuit*.

I.e. if you forgo having a cooker switch, and rely on being able to turn
off the MCB for the circuit, then you won't have a way of isolating the
appliance fully.

i.e. you should have an isolation switch (and yes they will be DP)