Cooker and hob rating

[davebullocklive]

Hi moved into a new house
On the consumer unit shower and immersion have been crossed out (they have been removed)
The breakers are now used for a cooker and hob

The cables are 2.5mm and wired as a ring for both
The cooker is 3.0kw and has a 20a breaker
The hob is 6.5kw and has a 30a breaker

Does this seem right ? I'm unsure how to work it out

 

[ban-all-sheds]

Already answered.

 

[sparkwright]

Already answered.

I'm not wading through that lot again.

This question probably need a topic of it's own, because it doesn't look like his electrician is going to be doing ANY of the work.

The 3 kW oven would seem to be ok on just a radial circuit wired in 2.5 mm on a 20 amp breaker - so why it's a 'ring' is anyone's guess.

Are you certain it's a ring, and not two radials in one breaker?

Perhaps one cable does the oven, the other cable does something else, eg immersion, etc.

You need to check this.

---

A 6.5 kW on a ring in 2.5 mm cable is unacceptable in my opinion. If it is how you describe, it sounds like this is an attempt to double up cable to make it bigger. Equally, it would also be in the form of a ring circuit, 30 amp MCB and all, but it's just not right.

You need to replace for a larger cable, probably 6 mm, but your electrician can work it out first.

 

[davebullocklive]

Already answered.

I'm not wading through that lot again.

This question probably need a topic of it's own, because it doesn't look like his electrician is going to be doing ANY of the work.

The 3 kW oven would seem to be ok on just a radial circuit wired in 2.5 mm on a 20 amp breaker - so why it's a 'ring' is anyone's guess.



Are you certain it's a ring, and not two radials in one breaker?

Perhaps one cable does the oven, the other cable does something else, eg immersion, etc.

You need to check this.

---

A 6.5 kW on a ring in 2.5 mm cable is unacceptable in my opinion. If it is how you describe, it sounds like this is an attempt to double up cable to make it bigger. Equally, it would also be in the form of a ring circuit, 30 amp MCB and all, but it's just not right.

You need to replace for a larger cable, probably 6 mm, but your electrician can work it out first.

There is no immersion in house as combi boiler
So the breakers are the right size but just the size of cable to hob needs upgrading ? Have checked breakers nothing else in house goes off so both wired as rings

 

[sparkwright]

I imagine there WAS an immersion heater. Check for unused switch or blank plate or junction box.

Or maybe the immersion supply was used to feed the boiler.

Check all this first, usually immersions were put in large cupboards.

 

[davebullocklive]

I imagine there WAS an immersion heater. Check for unused switch or blank plate or junction box.

Or maybe the immersion supply was used to feed the boiler.

Check all this first, usually immersions were put in large cupboards.

I'll take a look now under cupboard will report back

 

[flameport]

The cables are 2.5mm and wired as a ring for both
The cooker is 3.0kw and has a 20a breaker
The hob is 6.5kw and has a 30a breaker

Both circuits are wrong.
A 20A ring with 2.5mm cable is pointless and a waste of cable.
A 30A ring is designed to have the load distributed at multiple points, with each load not exceeding 3kW (and usually far less than that).

 

[davebullocklive]

Right here we go this is setup
View media item 83977
I unscrewed top switches there are 2 2.5mm cables in and 2 out

I unscrewed bottom blank plates under worktop /hob

There are 2 2.5 mm cables in

And then a much bigger white cable out of each 1 to hob 1 to cooker
Never seen this setup before !

Is it safe ?? In your opinions

 

[RF Lighting]

Doesn't sound great and certainly doesn't comply with regs, not that that seems to bother you.

 

[sparkwright]

It's certainly not right. The hob at least needs one larger cable instead - as opposed to two smaller cables doubled up.

 

[davebullocklive]

Does either comply ?

Are the mcbs correct size for the appliance if the cable was changed to correct size

 

[sparkwright]

A 3 kW oven can go on a 15/16 amp MCB, typically wired in 2.5 mm, but length of run and cable route in thermal insulation etc should be considered. So details needed.

A 6.5 kW hob can go on a 30/32 amp MCB, typically wired in 6.0 mm, but length of run and cable route in thermal insulation etc should be considered. So details needed.

 

[ban-all-sheds]

A 3 kW oven can go on a 15/16 amp MCB, typically wired in 2.5 mm, but length of run and cable route in thermal insulation etc should be considered. So details needed.

A 6.5 kW hob can go on a 30/32 amp MCB, typically wired in 6.0 mm, but length of run and cable route in thermal insulation etc should be considered. So details needed.

No point asking - he already has all of the information he needs to work out the cable sizes taking account of all of those details.

This question probably need a topic of it's own, because it doesn't look like his electrician is going to be doing ANY of the work.

We MUST NOT support or encourage or facilitate any of his dangerously ignorant bumblings.

Maybe he will go ahead regardless, and not for one second consider that his abysmal ignorance should in any way be a bar to doing the work, but it MUST NOT be with any connivance from us.

The ONLY thing we should tell him is to get an electrician. Anything else would be a shamefully irresponsible dereliction of duty.

 

[ban-all-sheds]

The 3 kW oven would seem to be ok on just a radial circuit wired in 2.5 mm on a 20 amp breaker - so why it's a 'ring' is anyone's guess.

We don't know that it is.

Are you certain it's a ring, and not two radials in one breaker?

He was asked that dozens of posts ago, and he ignored the question.

He doesn't have a clue.

You need to check this.

No!

His electrician needs to check that.

 

[davebullocklive]

A 3 kW oven can go on a 15/16 amp MCB, typically wired in 2.5 mm, but length of run and cable route in thermal insulation etc should be considered. So details needed.

A 6.5 kW hob can go on a 30/32 amp MCB, typically wired in 6.0 mm, but length of run and cable route in thermal insulation etc should be considered. So details needed.

Both lengths are 5 Mtrs from board to appliance (3.5 in ceiling through joists and 1.5 down plastered wall