new installation of 3.7kw oven 3.3kw hob

[ninjadude]

hi i'm installing a 3.7kw built in oven in a above oven housing unit. this appliance is in a different part of the kitchen to my new induction hob. the length of wire will be 8metres to connect them on the same radial circuit. then from the hob another 3metre length to the consumer unit. i'm going to connect them to a 40amp breaker in the CU and use a 45amp isolation switch which has a socket on it as well. does this sound ok because after the isolation switch i'm connecting 2 x 6mm wires, 1 to the hob and 1 going to the oven

 

[ban-all-sheds]

When you applied for Building Regulations approval, what did you say would be the way you'd comply with Part P?

• http://www.tlc-direct.co.uk/Book/6.2.1.htm
  
  
• //www.diynot.com/wiki/electrics:mcbtocable
  
  
• http://www.tlc-direct.co.uk/Book/4.3.1.htm
  
  
• http://web.archive.org/web/20080213151445/http://www.kevinboone.com/cableselection_web.pdf
  
  
• http://www.tlc-direct.co.uk/Book/5.3.1.htm
  
  
• http://www.tlc-direct.co.uk/Book/4.3.11.htm
  
  
• http://www.tlc-direct.co.uk/Technical/Charts/VoltageDrop.html
  
  
• http://www.tlc-direct.co.uk/Book/8.1.1.htm
  
  
• //www.diynot.com/wiki/electrics:part-p
  

 

[ninjadude]

i'm not an electrician, 'm doing work on my my own home

 

[ban-all-sheds]

1. You are still legally obliged to comply with Part P.
   
2. The work you are doing is notifiable and requires you to obtain Building Regulations approval in advance, and when you apply you will have to say how you will comply with it.
   
3. You must not work to a lower standard of safety than an electrician, so if you are going to DIY you have to learn and understand everything that's involved. And you have to be able to test your work before and after energising the new circuit.

 

[ninjadude]

i've noticed there was damage on the old cable so i think i'm allowed to replace it because its on a single circuit as stated in the building regs. are you complimenting me with your quote regarding the ark and the titanic lmao

 

[ban-all-sheds]

1. You are still legally obliged to comply with Part P.
   
2. Part P is not about notifying. Even if you try and wriggle out of notifying what is clearly a new circuit by lying about damage, the fixed appliances are also notifiable.
   
3. You still need to know what you are doing. You still need to learn and genuinely understand what you are doing, not just follow some electricity-by-numbers instructions, so get stuck into those links.
   
4. You still have to carry out testing. Do you know what tests you would carry out on the new circuit - what sequence you'd do them in and at what point you would energise it, and for each test do you know what is being measured, why it is important, how you would carry out the test, and with what equipment, and what sort of results you would expect to get if everything was OK?

 

[ninjadude]

thanks for your help.

 

[riveralt]

hi i'm installing a 3.7kw built in oven in a above oven housing unit. this appliance is in a different part of the kitchen to my new induction hob. the length of wire will be 8metres to connect them on the same radial circuit. then from the hob another 3metre length to the consumer unit. i'm going to connect them to a 40amp breaker in the CU and use a 45amp isolation switch which has a socket on it as well. does this sound ok because after the isolation switch i'm connecting 2 x 6mm wires, 1 to the hob and 1 going to the oven

It is unclear from your post how you are going to connect things up.
It is normal to work from the consumer unit (CU) to cooker switch and then the appliances.
So 3 metres from the CU to the hob and then 8 metres from the hob to the oven - where is the cooker switch going? It is recommended that appliances are no more than 2 metres from the cooker switch.
You need to be guided by the manufacturers instructions regarding the size of the MCB but 32Amp is the norm for this arrangement.
You also need the circuit protected by an RCD.
You need to ensure that the cable routes are within the safe zones and not affected by insulation as this will severley affect its current carrying capacity.
This work is notifiable to your Local Authority Building Control.
If you intend to do this yourself you should advise them immediately and pay their fee. They will want to know how you intend to test and certify that the installation is safe.
If you wish to ignore this advice then no-one here can help you further.

 

[ninjadude]

hey thanks for helping me, yes the cooker switch will be less than 2m to the front of the oven. also (3700w/230v) + (3300w/230v) + 5amp for single socket = 35amps. so is 40amp breaker in CU not right?

 

[ban-all-sheds]

That question was answered for you at 11:12 yesterday - why are you still asking it?

 

[riveralt]

hey thanks for helping me, yes the cooker switch will be less than 2m to the front of the oven. also (3700w/230v) + (3300w/230v) + 5amp for single socket = 35amps. so is 40amp breaker in CU not right?

No 3700+3300 = 7000/230 = 30.43A
Apply diversity:
(30.43 - 10) *.30 = 6.129+10+5 (for cooker switch) = 21.129A. Next higher MCB required - could be 25Amps but norm is to use 32Amp MCB.