calculating the de-rating of a cable near a heat source

[Neon Vagabond]

Im Working on a new build site at the moment, and the kitchen layout has changed to include an island with a hob on it.
Meaning im goin to have to get power to it.

The underfloor heating pipes have been run in already and the floor has been screeded.
Theres about 50mm before you get to the pipes. Pipes will reach 50 degrees max
My questions are;

1. Does anybody know if its against the regs to do this?

2. how can i calculate the de-rating of my cable?
was goin to use 6mm t+e in a conduit

 

[Neon Vagabond]

i am well aware that this not an ideal scenario but im trying to explore all possibilties

 

[Wilko]

Hi NV - I'm thinking Table 4A2 installation method 60, which is ref method B. Then temp derating from Table 4B1. How much load is there on the Island ?

 

[telectrix]

Hi NV - I'm thinking Table 4A2 installation method 60, which is ref method B. Then temp derating from Table 4B1. How much load is there on the Island ?

depends on the power rating of the music system playing the desert island discs. .

 

[Neon Vagabond]

i think its going to be a neff induction hob at 20A but i could be wrong

 

[Neon Vagabond]

so would a factor pf 0.71 mean a 70% capacity for current?

Its been a while since i done the whole calculations

 

[Wilko]

Hi - yes, that's how I read it too. So it's 10mm to get what 6mm would've done

 

[Neon Vagabond]

so just assuming its got a 40a capacity on a 6mm t/e then at 70% i calculate we are now at 28A.
So a hob with 20a capacity should be fine?