PV fed into sub board

[andrewcann]

hi all me and a friend are just about to go for our mcs and the install that my friend wants to show them is one that he did on a garage at the end of this garden. there is a sub bord down there but didnt no if it was ok to use that or if we would have to run a swa all the way back to the house ccu

 

[yellowvanman]

As far as using a sub main thats Ok, but for you its depends on the size of the cable from house to garage.

 

[andrewcann]

ok thanks is there a min size for the swa in the garage as there is pv down there or is it that it must be ok to take the extra 16amps

 

[yellowvanman]

Needs to take 16 amps if thats the size of your inverter but you need to aim for <1% volt drop.

 

[moggy1968]

If your voltage drop is too high the voltage may not be high enough (>1% as above) to overcome mains voltage so you can utilise PV output in the house. Your assessor will expect you to have looked at this (SMA's free online design tool will help you with this)
Also you need to make sure you aren't sharing an RCD with anything else (this configuration may not need an RCD, depends on the inverter) - lots of recent posts on here about that. The jury is out on the definitive answer but arm yourself with the arguments and counterarguments so if your assessor raises an issue you can dazzle him with diamonds (or baffle him with bull****!)
Also consider what earthng arrangements you need, agaiun, lots of posts on here about that.