6mm SWA cable

[Pete1960B]

Hi simple question can you tell me is 6mm the overall diameter of 6mm SWA cable please.

 

[charliegolf]

No, it is the cross sectional area of each wire in the cable. So, in twin and earth, each wire (conductor) will, when cut, look like a circle. The area of that circle is 6 square millimetres.

 

[Pete1960B]

Thanks charliegolf so what would be the overall diameter of 6mm twin and earth swa cable be then please.

 

[davelx]

it'll be 3-core, not twin and earth, and the overall dia is about 16mm (though may vary a little depending on make)

(twin & earth is a specific cable construction that is different from SWA cable)

 

[Pete1960B]

it'll be 3-core, not twin and earth, and the overall dia is about 16mm (though may vary a little depending on make)

(twin & earth is a specific cable construction that is different from SWA cable)

Thanks davelx is that because the armour is the earth on armoured cable. So i am not sure if electrician is using 2 or 3 core. I have to make an access point so he can get cable into bottom of garden room so needed to know the diameter of cable i will leave a 30mm gap so i know cable will fit.

 

[bernardgreen]

so needed to know the diameter of cable i will leave a 30mm gap so i know cable will fit.

You also need to know the minimum bend radius for the cable. For most SWA cables this is at least 6 times the diameter of the cable

 

[Pete1960B]

Accord

You also need to know the minimum bend radius for the cable. For most SWA cables this is at least 6 times the diameter of the cable

According to doncastercables website it will be 120mm

 

[davelx]

Thanks davelx is that because the armour is the earth on armoured cable. So i am not sure if electrician is using 2 or 3 core. I have to make an access point so he can get cable into bottom of garden room so needed to know the diameter of cable i will leave a 30mm gap so i know cable will fit.

It depends on a number of factors - sometimes 2 core can be used with the armour alone providing the earth (actually known as the Circuit Protective Conductor - CPC), sometimes the armour does not have a low enough resistance and the armour and the thirds core are used together as the CPC. In other situations two core may be used with the armour connected to earth at the origin only and isolated at the destination end, with a local earth rod being installed. Your electrician will know the appropriate method to use for your installation.

 

[securespark]

No, it is the cross sectional area of each wire in the cable. So, in twin and earth, each wire (conductor) will, when cut, look like a circle. The area of that circle is 6 square millimetres.

The live and neutral are 6mm².

The CPC is 2.5mm².

 

[chivers67]

Thanks davelx is that because the armour is the earth on armoured cable. So i am not sure if electrician is using 2 or 3 core. I have to make an access point so he can get cable into bottom of garden room so needed to know the diameter of cable i will leave a 30mm gap so i know cable will fit.

20mm will be large enough.