Sub Main

[ml1936]

What size SWA will be needed to supply a CU, which will only have a lighting circuit 6A, Shower 32A and Ring 32A?
The length of the sub main will be 50M tho

 

[davy_owen_88]

How long will the cable need to be?

Davy

 

[breezer]

How long will the cable need to be?

Davy

let me guess

The length of the sub main will be 50M tho

I guess 50M

 

[RF Lighting]

16.0mm² 3 core SWA will allow you a load of 68A (all your circuits at full load), over a distance of 50m.

I have not applied diversity.

 

[ml1936]

Cheers RF, but what about applying diversity? What would it be then 10mm?

 

[RF Lighting]

As it happens you still need 16.0mm²

 

[ml1936]

What bout if its XLPE from TLC does that make difference?

 

[RF Lighting]

Still 16.0mm²

Are you trying to get down to a 10.0m² to save some money?

 

[ml1936]

Save money, and effort putting it in, seems its a 50M run!

wudda thought XLPE rated at 73A wudda been fine

 

[RF Lighting]

Do you have switches etc rated to 90 degrees to take the XLPE?

Also the cable is 16mm² due to volts drop.

If you are going to all the effort of putting in 50m of SWA, then put in something that will also give you room for future expansion.

Stop being a tight arse and do the job properly.

 

[securespark]

He's got a job lot of 10 from e-bay & is reluctant to let go.....??

 

[RobFurn]

3 Core SWA. If your going to use this as single phase (2 core and earth) Cant it be treated as 2 core single phase i.e. 85A

For 3 core (3 phase) the CCC would be 73A. but if used for single phase cant you treat it as such and have an increased CCC.

What Im trying to say is are the tables and cable manufactures specs depandant on the use of the cable?

 

[ml1936]

It would be used as single phase neutral n earth, so is that true?

 

[ELZ4742]

is it 50mts detached from the building mains? if so AFAIK , it will need to be earthed with its own system i.e. a stake. so removing the need of the 3rd core.

perhapes someone in the know could clarify

 

[RobFurn]

It would be used as single phase neutral n earth, so is that true?

I dont know if its true Im just posing the quesiton for some of the more experianced sparks, Anyone?