Sorry, more noob questions!

I'm planning a new kitchen. The present electric cooker runs off a 32A spur.
I could just replace it with a new one, but would prefer a separate hob and
oven. The cooker incorporates a 13 amp socket and I can find an oven that
uses 13A or less. That leaves just under 20A available for the hob, ie about
5kw. Amazingly, I am struggling to find the power consumption of many hobs,
and those I have tracked down seem to be a bit higher, more like 6-7kw. Any
suggestions, please?



--
Murphy's ultimate law is that if something that could go wrong doesn't, it
turns out that it would have been better if it had gone wrong.

On Jan 27, 2:22*pm, "GB" wrote:
Sorry, more noob questions!

I'm planning a new kitchen. The present electric cooker runs off a 32A spur.
I could just replace it with a new one, but would prefer a separate hob and
oven. *The cooker incorporates a 13 amp socket and I can find an oven that
uses 13A or less. That leaves just under 20A available for the hob, ie about
5kw. Amazingly, I am struggling to find the *power consumption of many hobs,
and those I have tracked down seem to be a bit higher, more like 6-7kw. Any
suggestions, please?

--
Murphy's ultimate law is that if something that could go wrong doesn't, *it
turns out that it would have been better if it had gone wrong.

In a word DIVERSITY - "The first 10A of the rated current plus 30% of
the remainder of the rated current plus 5A for an integral socket ".

cynic wrote:
On Jan 27, 2:22 pm, "GB" wrote:
Sorry, more noob questions!

I'm planning a new kitchen. The present electric cooker runs off a
32A spur. I could just replace it with a new one, but would prefer a
separate hob and oven. The cooker incorporates a 13 amp socket and I
can find an oven that uses 13A or less. That leaves just under 20A
available for the hob, ie about 5kw. Amazingly, I am struggling to
find the power consumption of many hobs, and those I have tracked
down seem to be a bit higher, more like 6-7kw. Any suggestions,
please?

--
Murphy's ultimate law is that if something that could go wrong
doesn't, it turns out that it would have been better if it had gone
wrong.

In a word DIVERSITY - "The first 10A of the rated current plus 30% of
the remainder of the rated current plus 5A for an integral socket ".

Well, I agree that **in practice** a 32A socket will run cooking appliances
with a much higher load. The rings switch themselves on and off all the
time, so even with the oven and all 4 rings on, nearly all the time you'll
be running at much less than the rated current. I just didn't think you were
allowed to bank on that.





--
Murphy's ultimate law is that if something that could go wrong doesn't,
it turns out that it would have been better if it had gone wrong.

GB wrote:
cynic wrote:
On Jan 27, 2:22 pm, "GB" wrote:
Sorry, more noob questions!

I'm planning a new kitchen. The present electric cooker runs off a
32A spur. I could just replace it with a new one, but would prefer a
separate hob and oven. The cooker incorporates a 13 amp socket and I
can find an oven that uses 13A or less. That leaves just under 20A
available for the hob, ie about 5kw. Amazingly, I am struggling to
find the power consumption of many hobs, and those I have tracked
down seem to be a bit higher, more like 6-7kw. Any suggestions,
please?

--
Murphy's ultimate law is that if something that could go wrong
doesn't, it turns out that it would have been better if it had gone
wrong.

In a word DIVERSITY - "The first 10A of the rated current plus 30%
of the remainder of the rated current plus 5A for an integral socket
".

Well, I agree that **in practice** a 32A socket will run cooking
appliances with a much higher load. The rings switch themselves on
and off all the time, so even with the oven and all 4 rings on,
nearly all the time you'll be running at much less than the rated
current. I just didn't think you were allowed to bank on that.

I'll bet if you find the load plate for your existing cooker you will find
out that is exactly what you have been doing.

The OSG gives a maximum of 15kW for a household cooker with a 32A supply.

--
Adam

John Rumm wrote:

In practice (for domestic use) a 32A supply is more than adequate for
even a fairly large cooker. To work out what your design current for
the circuit is, take 10A plus 30% of the remaining load. Add on
another 5A if you have a general purpose socket on the cooker point
as well.
So for a 6.5kW hob, and a 3.2kW oven that is a 42A peak load. So if
you provision a circuit to supply 10 + 30% x 32 = 19.6A

I could see that working in practice - I just hadn't expected it to be
allowed by the regs. Thanks.


I've seen overloading quite recently. I lent my extension lead to a builder
to run his steam stripper off. He did not think to wind it all off the drum,
and the first I knew about it was when my PC went off. He had melted the
drum completely as well as enough of the cable sheath to cause a short
circuit. Even 5 minutes later the cable drum was too hot to touch.

On Jan 27, 11:25*pm, John Rumm wrote:
On 27/01/2011 14:22, GB wrote:

Sorry, more noob questions!

I'm planning a new kitchen. The present electric cooker runs off a 32A spur.
I could just replace it with a new one, but would prefer a separate hob and
oven. *The cooker incorporates a 13 amp socket and I can find an oven that
uses 13A or less. That leaves just under 20A available for the hob, ie about
5kw. Amazingly, I am struggling to find the *power consumption of many hobs,
and those I have tracked down seem to be a bit higher, more like 6-7kw. Any
suggestions, please?

In practice (for domestic use) a 32A supply is more than adequate for
even a fairly large cooker. To work out what your design current for the
circuit is, take 10A plus 30% of the remaining load. Add on another 5A
if you have a general purpose socket on the cooker point as well.

So for a 6.5kW hob, and a 3.2kW oven that is a 42A peak load. So if you
provision a circuit to supply 10 + 30% x 32 = 19.6A


So how much can I run on bellwire in conduit with fan cooling? And
neutral earthing


NT

"GB" writes:

I've seen overloading quite recently. I lent my extension lead to a builder
to run his steam stripper off. He did not think to wind it all off the drum,
and the first I knew about it was when my PC went off. He had melted the
drum completely as well as enough of the cable sheath to cause a short
circuit. Even 5 minutes later the cable drum was too hot to touch.

That's an interesting and useful warning.
I've been trying to dry out after a huge water leak from the flat
above, with the usual level of help from the inusurers [I swear that
typo was an accident; the subconscious in action again] who still
haven't got dehumidifier etc. in place.

My home-brew extension cord works well, but the drum unit I use for
outdoor work overheats. Not to the point of melting, and I've been
assuming that it was a flaky socket rather than the tightly-wound cable
which was responsible, but now I'm wondering.
Cable diameter suggests rather thin conductors so fairly high
resistance, despite the claim of a 13A. rating.

--
Windmill, Use m a i l
@ r m i l l
. a d s l 2 4
. c o . u k