Rcbo and rcd in series

[buzzlightyear]

a clue for him mv/ a/ m

 

[martinh89]

OK I think I'll go with separating it from the main tt, and creating its own tt and protect it from the submain, think this will be the easier option and prevent any inadvertent tripping.
Cheers for the replys

 

[buzzlightyear]

I've done my cable calculations and volt drop ect and sized the cable at 4mm/1.5mm swa because of the long run. The ze is 50ohms

There will be further decking and a longer run, I measured the garden at 89meters but I'll be ending the run at a out door socket at 65, just future proofed it, and yes there will be a socket but not prior to the board, it will be at the end.

this confuse me now 25amp fuse ?

 

[Pete999]

this confuse me now 25amp fuse ?

I have a head ache now

 

[westward10]

Unless the RCBO is single pole switched neutral or double pole then you will also trip the time delayed RCD as the neutral will remain connected in the event of a fault. You will struggle to find a SPSN RCBO or DP RCBO in single module form...only one I know of off the top of my head is SBS.

What time delayed rcd.

 

[telectrix]

even going up to 6.0mm SWA your VD @65m will be approx. 10V. assuming a Ib of 20A, so i think 4.0mm is a bit of wishful thinking.

 

[Leesparkykent]

What time delayed rcd.

Read post 9 and 10

 

[westward10]

Read post 9 and 10

Sorry Lee I jumped ahead

 

[HandySparks]

OK I think I'll go with separating it from the main tt, and creating its own tt and protect it from the submain, think this will be the easier option and prevent any inadvertent tripping.
Cheers for the replys

Separating the earthing systems won't do anything to prevent inadvertent tripping.

 

[suffolkspark]

I STILL DONT GET WHAT 4MM/2.5MM SWA IS?

 

[Pete999]

I STILL DONT GET WHAT 4MM/2.5MM SWA IS?

A new one on me as well