2x supplies down swa

[bigspark17]

does having two circuits travelling down one swa directly condradict a reg.?
Circuits in question are 2 63A submain down 1x 4c 16mm swa

 

[Richard Burns]

I do not believe there is any contravention there, two circuits in the same containment, just a little more difficult to separate. The armour would need to be suitable as a cpc for the worst case.

 

[westward10]

No it is fine, if it was conduit you wouldn't pose the question it is really no different.

 

[Spoon]

Interesting one. That figure would you use for grouping factors?

 

[Spoon]

I suppose you could use the 3 phase figure from the tables.

 

[LeeH]

I don't know the circumstances but isn't it worth taking all 3 phases if possible?

 

[DPG]

I don't know the circumstances but isn't it worth taking all 3 phases if possible?

Think he means 2 x single phase supplies in the one SWA.

 

[Chr!s]

Interesting one. That figure would you use for grouping factors?

Hi why would you need to group, its already rated assuming all conductors loaded?

 

[Spoon]

Hi why would you need to group, its already rated assuming all conductors loaded?

You have two single phase supplies going to different submains, in a 4 core cable.
Do you not think grouping should apply?

 

[westward10]

See Reg 521.7.

 

[LeeH]

Think he means 2 x single phase supplies in the one SWA.

Yes I know, just if it's possible take all 3 from the source or you could end up with 2 loaded up phases.

2 of 3 phase boards populated as single phase supplies.

Like I said no specific info but thought I'd ask.

 

[Chr!s]

You have two single phase supplies going to different submains, in a 4 core cable.
Do you not think grouping should apply?

Hi

In single phase what goes up must come down, so other than the proximity effect the CCC will be similar.

 

[westward10]

Treat it as a three phase supply for ccc.