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How many amp breakers?
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By *tu_b_man OP Man
over a year ago
Nottingham |
I’m waiting for the electrician to wire in my new oven and hob next week but I’d like to go out and buy the breakers for the consumer unit for him this morning. What amp size should they be?
The oven is 3.45kW
The hob is 4.6kW |
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By (user no longer on site)
over a year ago
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The oven needs a 16amp supply and the hob needs a 20amp supply. If i was you i would leave it up to the electrician to decide on what rating the breakers should be. The wiring for each appliance is a factor as is diversity. Leave the calculations up to the electrician. |
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By *tu_b_man OP Man
over a year ago
Nottingham |
"The oven needs a 16amp supply and the hob needs a 20amp supply. If i was you i would leave it up to the electrician to decide on what rating the breakers should be. The wiring for each appliance is a factor as is diversity. Leave the calculations up to the electrician."
Cool, got you. The oven has 10mm2 cable and oven 6mm2 cable running to it. |
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By (user no longer on site)
over a year ago
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I'm a kitchen fitter, so fit an oven and hob every week. We use the same electrician every week. Breaker ratings have a lot of maths involved to come up with the correct rating. Unless someone has seen the cable, worked out how long the cable run is, worked out the appliance manufactures specs and then added in diversity............they can't answer your question with any degree of certainty. |
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By (user no longer on site)
over a year ago
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It is no longer a simple case of this thickness for this and this thickness for another. There are complex calculations to be done as others have said depending on length, installation and other appliances. You should not even be thinking about it and any qualified and competent electrician will not let you near it in terms of circuit breakers of wiring. Leave it to the professionals! |
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By (user no longer on site)
over a year ago
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"I'm a kitchen fitter, so fit an oven and hob every week. We use the same electrician every week. Breaker ratings have a lot of maths involved to come up with the correct rating. Unless someone has seen the cable, worked out how long the cable run is, worked out the appliance manufactures specs and then added in diversity............they can't answer your question with any degree of certainty. "
professionals!"
Exactly, why make a, simple job easy when you can make it seem like science. All those houses that had their wiring done the old fashioned way constantly exploding, melting and burning.
Oh wait, they don't, nothing is happening to them at all except working.   |
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By (user no longer on site)
over a year ago
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"
professionals!"
Exactly, why make a, simple job easy when you can make it seem like science. All those houses that had their wiring done the old fashioned way constantly exploding, melting and burning.
"
No one is making it look like science. You obviously arn't aware of regulations regarding all electrical installations nowdays. An electrician, just like a gas fitter, has to be qualified and has to issue a certificate to the customer and Gas Safe or NICEIC. What might look like a simple job to you, can actually only be done by you if you are qualified and registered to one of the bodies i just mentioned.
Just try selling your house if you have had gas or electrical work done and have no certificate to prove it was done legally. |
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By (user no longer on site)
over a year ago
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"The oven needs a 16amp supply and the hob needs a 20amp supply. If i was you i would leave it up to the electrician to decide on what rating the breakers should be. The wiring for each appliance is a factor as is diversity. Leave the calculations up to the electrician."
This is sound advice |
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By *ootleCouple
over a year ago
Romford, Essex |
"The oven needs a 16amp supply and the hob needs a 20amp supply. If i was you i would leave it up to the electrician to decide on what rating the breakers should be. The wiring for each appliance is a factor as is diversity. Leave the calculations up to the electrician.
This is sound advice"
This IS sound advice, there is something called notifiable works (Part P of the building regulations). Your house insurance could be void if electrical work is carried out by someone who is not part of the self certification scheme (NICEIC, ECA etc).
Leave it to your qualified electrician - if anything goes tits up you can claim off him or the association he belongs to - and you also wont be breaking the law.
 |
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By (user no longer on site)
over a year ago
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"
professionals!"
Exactly, why make a, simple job easy when you can make it seem like science. All those houses that had their wiring done the old fashioned way constantly exploding, melting and burning.
No one is making it look like science. You obviously arn't aware of regulations regarding all electrical installations nowdays. An electrician, just like a gas fitter, has to be qualified and has to issue a certificate to the customer and Gas Safe or NICEIC. What might look like a simple job to you, can actually only be done by you if you are qualified and registered to one of the bodies i just mentioned.
Just try selling your house if you have had gas or electrical work done and have no certificate to prove it was done legally."
I'm very well aware of the, ridiculous unnecessary regulations, made to protect jobs for the boys. Most electrical work is ridiculously easy, so they've deliberately made it hard and certifiable to protect an industry. |
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By (user no longer on site)
over a year ago
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" I'm very well aware of the, ridiculous unnecessary regulations, made to protect jobs for the boys. Most electrical work is ridiculously easy, so they've deliberately made it hard and certifiable to protect an industry. "
Don't get me wrong, i'm 100% in agreement with you. Gas Safe and the NICEIC are one and the same company and have the entire construction industry stitched up, thanks to friends in government. Where i do differ is it's not to protect gas installers or electricians jobs.............the whole idea of it is to protect the very nice cosy well paid jobs of the peeps that run Gas Safe and NICEIC. |
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By (user no longer on site)
over a year ago
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" I'm very well aware of the, ridiculous unnecessary regulations, made to protect jobs for the boys. Most electrical work is ridiculously easy, so they've deliberately made it hard and certifiable to protect an industry.
Don't get me wrong, i'm 100% in agreement with you. Gas Safe and the NICEIC are one and the same company and have the entire construction industry stitched up, thanks to friends in government. Where i do differ is it's not to protect gas installers or electricians jobs.............the whole idea of it is to protect the very nice cosy well paid jobs of the peeps that run Gas Safe and NICEIC."
OK, that's probably even more true. Not that I have anything against electricians and has fitters. Gas scares me anyway. Its just the unnecessary red tape and forcing it on unaware people. |
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"I’m waiting for the electrician to wire in my new oven and hob next week but I’d like to go out and buy the breakers for the consumer unit for him this morning. What amp size should they be?
The oven is 3.45kW
The hob is 4.6kW"
The advice you’ve had previously is sound . Don’t take any chances and leave it to the experts . The regulatory bodies are over the top when it comes to certification and testing requirements but it’s better to be safe than sorry .  |
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By (user no longer on site)
over a year ago
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Let the electrician do it. We had a whole fitted kitchen in 2014 and every appliance came with an ordinary 3 pin plug, including oven and induction hob. I was impressed. |
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By *tu_b_man OP Man
over a year ago
Nottingham |
"The oven needs a 16amp supply and the hob needs a 20amp supply. If i was you i would leave it up to the electrician to decide on what rating the breakers should be. The wiring for each appliance is a factor as is diversity. Leave the calculations up to the electrician."
Interestingly, the sparky fitted the oven with 20amp and hob with 30amp. Hope this was right?!  |
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By *ootleCouple
over a year ago
Romford, Essex |
"The oven needs a 16amp supply and the hob needs a 20amp supply. If i was you i would leave it up to the electrician to decide on what rating the breakers should be. The wiring for each appliance is a factor as is diversity. Leave the calculations up to the electrician.
Interestingly, the sparky fitted the oven with 20amp and hob with 30amp. Hope this was right?! "
Just a little concerned you have mentioned 30amp - hopefully you mean a 32A (the former would be an BS 3036 rewireable fuse while the latter is a circuit breaker).
Two questions that will hopefully put your mind at rest;
1. Were the hob and oven wired as a ring circuit or a radial circuit?
2. what were the cable sizes?.
You can easily find this out by looking at the paperwork he left you, in the schedule of test results, there is a column with a heading 'Ring Final Circuit Continuity' if these 3 columns (line, Neutral, cpc) are filled in then it’s a 'ring circuit’ if these 3 columns are blank then look just to the right.
The 2 columns under the heading 'Continuity  (R1+R2) or R2' - if the (R1+R2) column is filled in then you have a radial circuit.
Now, if you look to the left there is a Colum under conductor details that states 'Live' (mm²) in this column it should show either of the following:
For the oven: it should be 2.5mm² for a ring circuit and also 2.5mm² if it’s a radial circuit.
For the hob: it should be 2.5mm² for a ring circuit or 4mm² if it’s a radial circuit.
I’m assuming this an average size everyday family home and not a commercial installation or a 12 bedroom mansion where the ‘fuse board’ is in the West Wing !
 |
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By *tu_b_man OP Man
over a year ago
Nottingham |
"The oven needs a 16amp supply and the hob needs a 20amp supply. If i was you i would leave it up to the electrician to decide on what rating the breakers should be. The wiring for each appliance is a factor as is diversity. Leave the calculations up to the electrician.
Interestingly, the sparky fitted the oven with 20amp and hob with 30amp. Hope this was right?!
Just a little concerned you have mentioned 30amp - hopefully you mean a 32A (the former would be an BS 3036 rewireable fuse while the latter is a circuit breaker).
Two questions that will hopefully put your mind at rest;
1. Were the hob and oven wired as a ring circuit or a radial circuit?
2. what were the cable sizes?.
You can easily find this out by looking at the paperwork he left you, in the schedule of test results, there is a column with a heading 'Ring Final Circuit Continuity' if these 3 columns (line, Neutral, cpc) are filled in then it’s a 'ring circuit’ if these 3 columns are blank then look just to the right.
The 2 columns under the heading 'Continuity (R1+R2) or R2' - if the (R1+R2) column is filled in then you have a radial circuit.
Now, if you look to the left there is a Colum under conductor details that states 'Live' (mm²) in this column it should show either of the following:
For the oven: it should be 2.5mm² for a ring circuit and also 2.5mm² if it’s a radial circuit.
For the hob: it should be 2.5mm² for a ring circuit or 4mm² if it’s a radial circuit.
I’m assuming this an average size everyday family home and not a commercial installation or a 12 bedroom mansion where the ‘fuse board’ is in the West Wing !
"
Cool that makes sense.
In answer your questions....
1. They are both radials
2. The hob is on a 10mm2 cable and the oven is on a 6mm2 cable
The hob is on a 32amp breaker (sorry, typo previously). The oven is on a 20amp breaker.
The hob is 4.6kW
The oven is 3.45kW
As for paperwork, he didn’t leave anything but he’s sent me the bill! What is the document called? He’s with napit. Might try looking him up on there just as a sanity check lol |
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