Awa cable? Any information would be helpful thanks

[Davehaywire]

doing an eicr
I noticed the cable feeding the service head on 3rd floor from ground floor is a 1x25mm awa cable
From the service head 3rd floor it’s your normal tails to dB in flat
So the awa cable is being used as below
The inner core used as line
The outer sheath (unsure on mm size of this anyone?) is being used as neutral and earth
Does anyone know about this set up as I haven’t seen it before?

 

[westward10]

It's a concentric cable.

 

[Deleted member 26818]

Are you sure it’s AWA, not copper concentric?
Aluminium conductors are usually larger than Copper and require special lugs for terminating.

 

[westward10]

AWA stands for Aluminium Wire Armour and the line core can be copper or aluminium.

 

[Deleted member 26818]

AWA stands for Aluminium Wire Armour and the line core can be copper or aluminium.

Yes, usually used with 3 phases to prevent eddy currents and made off into an Aluminium gland.
The AWA usually has a lower CCC than the core, as it is only being used to provide earth fault protection.

Not sure a reduced CCC would be acceptable when the AWA is being used as a PEN conductor.

 

[westward10]

I don't think it is AWA. If it has an aluminium core and is concentric the outer conductor is likely to be copper.

 

[davesparks]

Are you sure it’s AWA, not copper concentric?
Aluminium conductors are usually larger than Copper and require special lugs for terminating.

It doesn't always need special lugs, barrier grease can be used to terminate aluminium into brass terminals. This is how DNO's terminate aluminium concentric cables into standard cutouts.

 

[MJPD29]

I agree it is more likely to be concentric

 

[Davehaywire]

I don't think it is AWA. If it has an aluminium core and is concentric the outer conductor is likely to be copper.

Yes I can see the outer core is copper but I can’t See if it’s aluminium inner core, it’s terminated.
What would the csa of the outer copper sheath be , if the inner core is aluminium 25mm ,(this is being used for cpc and neutral

 

[westward10]

That is probably DNO property as concentric cables cannot be used for general wiring.