Cable sizing a shower

[Mike2007]

9kw shower
30m cable length
SWA
Clipped direct outdoors uncovered
What would the CSA be on the cable?
Cheers in advance

 

[EFLImpudence]

9kW @ 240V = 37.5A
so 40A MCB.
so 4mm. SWA clipped or buried in masonry.

You might care to use 6mm² to cover a larger shower.

 

[delmel]

don't forget has to have an RCD

 

[Londoner2]

4mm???

I thought a 10mm is the right choice.

 

[winston1]

4mm???

I thought a 10mm is the right choice.

You thought wrong.

 

[Mike2007]

First time I have ever heard someone suggest 6mm for a 9kw shower.
And like the other poster implied, 4mm sounds extremely light for drawing all those amps?
It was 30 metres, not 30 centimetres.

 

[oldbutnotdead]

First time I have ever heard someone suggest 6mm for a 9kw shower.
And like the other poster implied, 4mm sounds extremely light for drawing all those amps?
It was 30 metres, not 30 centimetres.

Well do the sums rather than relying on instinct. Cable type and installation method are more important than you might think

 

[EFLImpudence]

First time I have ever heard someone suggest 6mm for a 9kw shower.

You need to get out more.

I suggested 4mm².

9kW @ 240V is 37.5A
4mm² SWA has a Method C CCC of 42A, and
6mm² 53A
10mm² 73A

And like the other poster implied, 4mm sounds extremely light for drawing all those amps?
It was 30 metres, not 30 centimetres.

If it sounds wrong, you are listening to the wrong things.