Shower Circuit

[Geffers]

Don,t get annoyed guys yet another shower question, 10.5kw shower to be fitted in a bungelow it is 10m from the board (RCD protected) & will be clipped direct, i will use 10mm cable so - calculated = P/V = 45.6A no problems so far, the usual factor is that the protective device must be equal to or more than the resulting figures (lb<ln). However the OSG only goes up to 45A rating & for 10mm cable allows only BS1361 to be used. I cannot find in the regs if 50A mcb is going to be ok. can any of you fine gentlemen point me in the right direction or have i got my calcs wrong.

Please only helpful replies no criticism i have not had a drink for 5 x days!

 

[lilygee]

Use a 50A mcb. As long as your mcb is sized to cut out before your current carrying capacity of your cable, you're alright. Regs says that's 80 amp for 10mm clipped direct, so no worries

 

[PC Electrics]

A 50A mcb is fine for this application.From table 4D5A the rating of 10mm t&e clipped direct is 64A.

---------- Post Auto-Merged at 19:05 ---------- Previous post was made at 19:04 ----------

As it's clipped direct you could use 6mm and a 45A mcb (if one is available for the make of board)

 

[Geffers]

Great stuff best forum on the net i knew you guys would,nt let me down.

thanks a lot. Going for a drink now as its bank holiday tomoz

Geffers

 

[PC Electrics]

Ah! 'tis true Geff. I might even have managed to attract someone here from the 'dark side'.

We do have one pet hate though - text talk. It seems to be creeping in more and more.

 

[batty]

What size is main fuse if its 60 amp may be an idea to get customer to get it upgraded.

 

[WarrenG]

Also bear in mind any thermal effects when routing your cable. This will have a derating effect on the circuit.

 

[Andy™]

Use a 50A mcb. As long as your mcb is sized to cut out before your current carrying capacity of your cable, you're alright. Regs says that's 80 amp for 10mm clipped direct, so no worries

er.... its not as simple as picking a breaker thats lower than the cable capacity. to start with, you also need to make sure your within Zs.

 

[Geffers]

Apologies PC i will endeavour to communicate all future interactions using only the Queens english.

:Salute

 

[Sidewinder]

Geffers,

It's just that us "older" folks have a problem understanding some of the text talk!!!

 

[Sidewinder]

ME!

B/Day last Friday so another year older!

Getting closer to 50 year by year.