Cable from loft to CU

[sedgy34]

I would put 6 mm t&e in and cap it with 3 mm sheathing

 

[SolarCity]

Ok. So 6mm is the way to go...

My next question is using SWA a good idea so that the cable run doesn't need RCD protection?

Depends where you're running it. Sometimes it is best to run the cable on the outside of the house (although no need to do this with a rewire - which is what I assume you are doing) If you can get the cable into the loft (or garage) without sinking the cable in then you shouldn't need SWA.

 

[Octopus]

Depends where you're running it. Sometimes it is best to run the cable on the outside of the house (although no need to do this with a rewire - which is what I assume you are doing) If you can get the cable into the loft (or garage) without sinking the cable in then you shouldn't need SWA.

The cable would be added as part of a major refit, so yes its a rewire, and no I don't want a cable on the outside of the house unless I have to, or trunking on the inside.

 

[sedgy34]

Do post 41 then

 

[Octopus]

Do post 41 then

Yup, sounds like a plan!

 

[Dale200bhp]

I would just put a steel 25mm conduit with endbox behind consumer unit straight up into the loft in the corner if you can (im asumeing con unit would be in a corner), then you can pull in what you want at later date.

On the timber frame houses we do we stick a 25mm plastic conduit straight to loft for solar at later date, and its behind the stud work so it will be 125mm back from the surface too.

I would advise however to install inverter else where, im not keen on installing them in lofts although many do.

 

[moggy1968]

SWA may not be regarded as sufficient protection against nails and the like if burried in a wall less than 50mm. neither is metal capping.

 

[moggy1968]

No, you're right Gavin, never on a shared RCD. Most TL manufacturers will tell you that their unit exhibits about 20mA AC leakage under normal operating conditions. Odd though, that SMA "recommend" a 100mA min trip limit (to avoid nuisance tripping) and I could be mistaken but didn't P1 always recommend a 300mA trip limit, per inverter - although that could be due to the fact that most of mainland Europe (especially Germany curiously) don't consider a 100mA trip limit RCD as a standard rating, normally using either 30mA or 300mA.

So, we know in practice that a 30mA limit on a dedicated circuit is generally ok with a good quality TL unit (damp mornings are when a problem will typically materialise as we know) but on the other hand we have manufacturer's recommendations to follow....what to do? ;-)

which is why I didn't understand your previous post! Hence Huh!