Neff B1421 Oven (Built-in) Install

[DavePrior]

Guys,
Need your help please. 2.8Kw Neff built-in oven, no cable, installation kit etc. I was expecting 3 core flex and a plug.
Manual states H05VV-F cable, which I understand to be 3-core flex.
Idiot questions now:
1) Since P=IV, then I=2800/230 which is about 12 amps. Is it permissible to simply put a plug on and connect into the kitchen ring-main (ordinary 2.5mm T&E) ?
2) manual (sic) also talks about an isolation switch. Is this necessary?
3) Does H05VV-F have heat resistant qualities? And can I replicate these qualities with flat 2.5mm T&E and heat-resistant sheathing?
4) H05VV-F comes in different conductor sizes. Begging question (1), I guess I would need 2.5mm?

Many thanks for your help and patience

 

[securespark]

Best to contact mfr, don't guess.

But flex used by mfrs for 13A is usually 1.25mm², some use 1.5mm² as 1.25 difficult to find.

Look in reference for cable coding - if it is not HR(heat resisting), you can use ordinary flex. If the oven is built-in, then an isolation switch is a good idea.

One way to do this would be to take the ring (or your radial feed) to a 20A DP switch and then run the load side to a single socket convenient for the oven.

 

[ban-all-sheds]

Manual states H05VV-F cable, which I understand to be 3-core flex.

Info on decoding cable specs like that is in the For Reference section

1) Since P=IV, then I=2800/230 which is about 12 amps. Is it permissible to simply put a plug on and connect into the kitchen ring-main (ordinary 2.5mm T&E) ?

Yup.

2) manual (sic)

What's wrong with "manual"??

also talks about an isolation switch. Is this necessary?

Not if the socket where you plug it in is accessible.

3) Does H05VV-F have heat resistant qualities? And can I replicate these qualities with flat 2.5mm T&E and heat-resistant sheathing?

Why use T&E? It's not designed to go into plugs. Use flex

4) H05VV-F comes in different conductor sizes. Begging question (1), I guess I would need 2.5mm?

1.5mm² will be ample.

 

[DavePrior]

Thanks guys - most appreciated.

BAS - manual comprises about 10 lines of install info, hence the (sic) !
Maybe I expect too much

I've put a double socket directly behind where the oven will be housed, so I'm looking at an isolation switch. Trying to avoid using one of the large clumsy ones (naturally, if safety and regs won't allow me this then so be it), so can I use a switched 13A FCU? And will this be wired as load one side & supply the other, or as an inline on the phase?

Once again, many thanks for your help in this.

 

[andy]

might be easier to hard-wired the PCU into the ring main, and then flex from the FCU to the oven. OR, take T&E (buried) to behind cooker and put a connection plate then wire in flex from there to oven

 

[securespark]

The FCU is a DP switch, so you will have L IN and N IN to which you connect the feed, and L OUT and N OUT to which you connect the load. The switch will disconnect both L & N from the appliance.

 

[DavePrior]

Nice - thanks once again all

 

[ban-all-sheds]

As the oven is a fixed appliance, do you plan to notify LABC, or do the work last year?

 

[DavePrior]

Building notice all filled out, complete with my amateurish diagrams. I've got a NICEIC reg'd electrician lined up to install a new CU and do pre-install test and certify, and naturally post-install certify.
Spoke with building control a number of times - very helpful guys.

I think I've covered it - is there anything I've missed?

Once again - many thanks...much appreciated.

 

[ban-all-sheds]

Crazy, isn't it.

If it were a free-standing device, you could put a plug on it, and plug it in. Because it fixes into an item of kitchen furniture, which electrically means SFA, you have to jump through all these hoops.

And all because of the utterly cynical, self-serving, money-grabbing attitude of the electrical contracting industry bodies.

 

[DavePrior]

Whilst I'm obviously not qualified to comment on that, I must say I can't argue! Their first stab at ensuring mugs like me don't kill anyone?

One last one, if I may. The normal 45amp cooker isolation switches aren't fused (but OK, they have their own MCB). Do I have to use a fused switch? (think I've just answered my own question, but I'd appreciate your thoughts!)

Must owe u several pints by now.....

 

[ban-all-sheds]

If you are supplying the oven via 1.5mm² flex from a cooker circuit then yes, as the rating of the circuit fuse/MCB will be too high to protect the flex.

Same applies to coming from a 30/32A socket circuit.

 

[DavePrior]

Gentleman and a scholar.
I'll update this once the LABC inspectors have inspected, and my NICEIC guy has tested and certified, in case they throw up anything of interest/enlightenment/humour.

 

[DavePrior]

LABC guy was in & out in 5 mins
Now just wants to see the final certs from the NICEIC sparkie.
16th Edition On-Site Guide came in handy with both - was recommended this book by a sparkie friend.