SWA to garage

[cor]

just looking for guidance,

was thinking of getting power to my garage and futureproofing for EV car if i ever go that way

it would have a radial set of sockets 5 doubles i think, lights and the space in the box for EV set up surge protector and RCD

i might run an air compressor - maybe a welder at times 

i wondered if catenary wire set up is ok instead of underground and if 16mm 3 core with cat5  is the right size or too big? probably 30m run from CU to unit in garage

no water in the garage atm but i might go that route 

was going to just use the earth to the house extended to garage and not add a TT rod set up

 

the house is on an old board 1975 which i will change- plug in fuse with wires

the earth set up appears TN C S  as there is not earth band to the incoming supply

100amp fuse

 

simple single skin block garage

TIA

 

 

 

 

 

[Nickfromwales]

30m should be fine to export the supplied earth, and I’d defo go with the 16mm2 to stave off voltage drop and give some headroom, but you could probably get away with 10mm2. 
 

Catenary is fine, just remember to get duct grade CAT6 (I don’t use CAT5 anymore). 
 

That SWA can be protected by a 50a breaker, and should allow use of most things even when the EV charger is in use.

 

I’d only recommend a rod and isolating the earths if this was a metal clad building.
 

 

[Nickfromwales]

Surge protection would only be installed in the new CU in the house   no need for a secondary one in the remote CU. 

[cor]

21 hours ago, Nickfromwales said:

30m should be fine to export the supplied earth, and I’d defo go with the 16mm2 to stave off voltage drop and give some headroom, but you could probably get away with 10mm2. 
 

Catenary is fine, just remember to get duct grade CAT6 (I don’t use CAT5 anymore). 
 

That SWA can be protected by a 50a breaker, and should allow use of most things even when the EV charger is in use.

 

I’d only recommend a rod and isolating the earths if this was a metal clad building.
 

 

 

morning nick

thanks for the reply

i only saw the surge protection in the garage of my friend who has an ev and when i looked online any of the EV type boxes had them in there- so just assumed it would be there.

 

ive seen the integrated ev ultra swa 16 in cat5 and cat 5e  but cant see much in a cat 6 version- i assume there is some induction issues if running them as separate cable type for a 6 but together on the wire

 

i was going the route of box profile on roof and walls batten to the block.....either way the roof will be box profile

 

 

cheers

[Alan Ambrose]

>>> i assume there is some induction issues if running them as separate cable

 

I've never looked at the EV ultra cable in the flesh - but barring some proper magic, I can't imagine that SWA with its armour earthed and cat 6 with a screen foil will have much in the way of induction.

[cor]

On 14/05/2025 at 19:46, Alan Ambrose said:

>>> i assume there is some induction issues if running them as separate cable

 

I've never looked at the EV ultra cable in the flesh - but barring some proper magic, I can't imagine that SWA with its armour earthed and cat 6 with a screen foil will have much in the way of induction.

 thanks for the reply