Cable for storage Heaters

[shaw7380]

Is 1.5mm 3 core heat resistent flex suitable for a storage heater, from switch to appliance obviously.

And is the 2.5mm twin and earth thats there to supply the switch adequate

 

[plugwash]

sounds fairly normal to me. what rating is the storage heater?

 

[shaw7380]

need to get back to you on that plugwash

 

[mapj1]

2.5mm is good for at least 20A (nearly 5000 watts say) depending on how well it can cool itself (27A in free air)
1.5mm flex is good for 12A, so 3000 watts approx.
The rating should be clearly marked on the makers plate.

 

[shaw7380]

One of the heaters is 2.5kw the other is 3.4kw

 

[mapj1]

the larger one could do with the next size up of flex.

 

[plugwash]

i've always seen 1.5mm flex sold as 15A where do you get your 12A figure from.

now in this situation it may be running hot but its high tempreature flex as well so precisely working out the rating is made a little trickier.

 

[mapj1]

Oops fingers on the wrong line in the tables... (looking at 1.25mm)
It would probably just do 4KW in 1.5mm, assuming it is mounted so it can cool itself.
Mind you, the next size up would do no harm..

 

[felix]

Where are the fuses and what size are they? If the only fuses/breakers are the ones in the consumer unit then these dictate the size of all the cable and flex that lies downstream. If the switches have smaller fuses of their own you can use smaller flex.