cooker/hob wiring

[bigt]

Bob,
What is the accepted method to connect the hob and oven,both of which will be within 2metres of the CCU?Do I need to be running a 10mm and a 6mm across the house to feed them,as plugwash suggested.Should I use two 45amp isolators? Space is a bit limited on the wall and I don't really want it full up of sockets,a bit of a job tiling afterwards! even though I will remove all the sockets and refit them afterwards for neatness.I have got to get in 3 double sockets,2 3amp fused switches for lights,1 3amp fused switch for chimney and whatever is required for the oven and hob!Is one 10mm cable to the CCU and two out of it OK (both 10mm if possible to get them in)or two cables,one 10mm,one 6mm with 2 45amp isolators?

 

[BobRathbone]

Ban all sheds should recognise the need to classify some circuits as 'exclusive circuits'. By doing this the designer of the circuit is able to accurately caculate the loading and other conditions that the circuit may have to meet. I trust that the wiring to the contactor coil is rated greater than or equal to the rating of the protective device at the origin of the circuit. ie it is 6 or 10mm. You may think that 10mm for a contactor coil is silly, but what would happen if the wiring to the coil developed a short circuit or eath fault? Fire could result. If the wiring is smaller it must be protected by a fuse at the point the conductor size reduces, that will probably be in the shower or in the isolator, you do have an isolator B.A.S.?
Anyway, if I was called to test and certify this circuit I would have to mark it down as a deviation from the regulations and refuse to issue a certificate.
The solution to the problem would be to connect the fan to the lighting circuit as is normal, or use a PIR away from the shower, say over the door, to trigger the fan. Use the PIR timer and you don't need a timer on the fan, it will stay on as long as you keep moving.
They don't make the regulations to make things difficult for us, they are to keep us safe from electric shock and fire.

How do I know all this? Well, I am a fully qualified electrician and have spent the last 10 years + teaching the 16th edition regulations along test and inspection to qualified electricians in the West Midlands and Shropshire.

 

[ban-all-sheds]

Ban all sheds should recognise the need to classify some circuits as 'exclusive circuits'. By doing this the designer of the circuit is able to accurately caculate the loading and other conditions that the circuit may have to meet.

Sorry - I didn't realise that accurately adding the load of a cooker hood to the load of a cooker was too difficult for a designer to do.

I trust that the wiring to the contactor coil is rated greater than or equal to the rating of the protective device at the origin of the circuit. ie it is 6 or 10mm.

It's 10mm².

You may think that 10mm for a contactor coil is silly, but what would happen if the wiring to the coil developed a short circuit or eath fault? Fire could result. If the wiring is smaller it must be protected by a fuse at the point the conductor size reduces,

Thank you. I did know that, which is why I've used 10mm². On what basis have you decided that I might think it's silly?

that will probably be in the shower or in the isolator, you do have an isolator B.A.S.?

Were you as condescending as that when you were a teacher?

Anyway, if I was called to test and certify this circuit I would have to mark it down as a deviation from the regulations and refuse to issue a certificate.

If you didn't mind me then refusing to pay you, that'd be fine.
Which regulation does it contravene?

The solution to the problem would be to connect the fan to the lighting circuit as is normal,

That's not a solution - I don't want the fan to come on just because someone has turned the light on. The light doesn't make steam. Your design fails to meet a mandatory customer specification.

or use a PIR away from the shower, say over the door, to trigger the fan. Use the PIR timer and you don't need a timer on the fan, it will stay on as long as you keep moving.

That's not a solution - I don't want the fan to come on just because someone has entered the bathroom. Someone just being in there doesn't make steam. Your design fails to meet a mandatory customer specification.

They don't make the regulations to make things difficult for us, they are to keep us safe from electric shock and fire.

What is there about this:

that is unsafe?

How do I know all this? Well, I am a fully qualified electrician and have spent the last 10 years + teaching the 16th edition regulations along test and inspection to qualified electricians in the West Midlands and Shropshire.

Did you ever teach them to think for themselves?

 

[bigt]

Bob,
Finally found out cooker rating 4.3KW and hob rating of 6.4KW!I will be running a 10mm cable for the double oven (in case a freestanding appliance gets put in at a later date) and a 6mm for the hob.The 10mm going through a cooker control unit and the 6mm via a 45amp double pole switch.Have completed ring main for sockets/lights etc.Just got to find someone to change over my consumer unit and repair the walls!!But that's another storey!!!Thanks for help.

 

[fiz]

here is a quandary

I have just had a look at my mums wiring

she has a 32 amp fuse on a radial
circuit 4mm supplying down stairs and kitchen

the hob is gas but the cooker (not sure of amps)is electric

the microwave tv cooker washing machine
kettle are all on the same circuit.

they are aware of this but do not want to rectify it

do i have to. knowing the dangers

 

[plugwash]

bas one little question about that setup

what kind of fuse did you use and in what kind of carrier?

i would imagine that din rail units to take plug fuses are quite rare and 3A is not a standard size for other types of fuse.

 

[ban-all-sheds]

It's actually a 3.15A fuse - IEC 127-2 spec, in a 5 x 20mm format

According to the data sheet, at 15A (Iz for 1mm² T/E) it will operate in less than 0.2s, and at 1.45Iz in less than 0.06s

I could replace it with a 1A, for which those times would be approx 0.006s and less than 0.002s respectively, but I don't think I need to....

 

[securespark]

As they chant on Jerry Springer, "Go, Girl!!"

 

[Eve]

Could you please advise, at the mo we have a switch for the cooker and a socket together under the extractor fan. the extractor fan has the wire out of the top which then runs down the side of the extractor and plugs in to the socket, is this the best way or is there any way of hiding the wire?