Mcb rating shower

[bathroomboy]

Installing 8.5kw shower which will pull 37 amps, looking at shower cu with rcd, but it comes with 50a mcb will it be ok to overrate or should I change the mcb to 40a.

 

[DHES-LTD]

Installing 8.5kw shower which will pull 37 amps, looking at shower cu with rcd, but it comes with 50a mcb will it be ok to overrate or should I change the mcb to 40a.

I'd change it to a 40 if its on 10mm cable.

 

[acat]

You would be better of fitting a 32A as mcb should be the same as or lower than the current carrying capacity of the cable as your mcb is meant to protect the cable if I remember correctly thats for 6mm cable or as the post above


Chris

 

[DHES-LTD]

Yeah you're right acat, i have a 9.8kw shower at home, 10mm cable but i put it on a 32A MCB and hold in fine on full power.

 

[acat]

Decided to have a look if you use the 50A mcb provided it should be on a 16mm cable


Chris

 

[sparkswillfly]

bs en 60898 only requirs a 32a mcb to operate within 1 hour when carrying 40a

 

[electro]

You would be better of fitting a 32A as mcb should be the same as or lower than the current carrying capacity of the cable as your mcb is meant to protect the cable if I remember correctly thats for 6mm cable or as the post above


Chris

Hi


Ib should be less than or equal to In, and In should be less than Iz. Not In less than Ib...


Regards

 

[bathroomboy]

Thanks for thr replies lads

 

[flukey]

Decided to have a look if you use the 50A mcb provided it should be on a 16mm cable


Chris

you sure about that acat nobody mentioned the installation method but method C 10mm is fine on that mcb