undersized cable provided by electric hob/cooker manufacturer?

[impish15]

Hi All,

I am a little confused, probably something I am missing.....

I have just wired in a 7.4kw Neff V57THQ4L0 N70 Vented Hob. I ran a supply of 6mm from the board for the hob. My confusion is why the manufacture has provided a 1.5mm cable for me to wire this into the cooker connection unit. Is this common practice? Isn't the cable provided from the manufacturer massively undersized?

Many thanks

 

[littlespark]

Yes. It’s common practice.

We are trained to use diversity with high loads, and take the rated full load of the appliance….

However, the hob itself may have electronic load management built in… it will never take the full load, or anything near the CCC of the cable

 

[James]

Can you post the installation instructions? Can’t find them online.

 

[snowhead]

It's common on many appliances, check the cable size on most electric kettles.

 

[impish15]

Yes. It’s common practice.

We are trained to use diversity with high loads, and take the rated full load of the appliance….

However, the hob itself may have electronic load management built in… it will never take the full load, or anything near the CCC of the cable

Ok thanks for confirming. I wasn’t aware of this. Many thanks

 

[Teddy Lop]

Is it a 5 core with parallel L+N? This is quite a nifty solution imo and far nicer to work with than 4mm flex.

If the hob is 7.4kW rated it won't be managing the load down from that, I've seen 5 ring hobs that manage the load to 3 kW, complete with plug top, complete junk IMO.

 

[impish15]

Is it a 5 core with parallel L+N? This is quite a nifty solution imo and far nicer to work with than 4mm flex.

Yes 5 core with parallel L+N

 

[impish15]

Can you post the installation instructions? Can’t find them online.

Photo attach from the back of it.

 

[nicebutdim]

Yes 5 core with parallel L+N

Something to think about in relation to your original question.

 

[Teddy Lop]

Yes 5 core with parallel L+N

Well there's your answer, it's not 1.5, it's 1.5*2.

I've always wondered why more use isn't made of parallel runs.

 

[littlespark]

Ah… 5 core, so that in other country markets that it’s sold in, they can utilise the local electricity systems…. 2L + 2N or 3P + N

 

[freddo]

I've always wondered why more use isn't made of parallel runs.

I guess it's normally only really worth while for larger things. It's much easier to run 2x 150mm2 4 core SWAs than 1x 300mm3 SWA for example. The cable costs are higher buying 2 cables but if it saves a lot of effort or the routes are difficult for stiff cables it is worth it. On a smaller scale I do have a 4H4 MICC feeding a small single phase distribution board in my house, with the conductors paralleled, though this was mainly as the cable was to hand. The main drawback is it's a big problem if one core gets disconnected.

 

[freddo]

I actually did it with a 4 core 4.0mm swa last week!