Fused rcd versus swa

[tuckermot]

house consumer unit has no rcd !!!! tn cs earth system

job description

power to garden pump !!

option 1
fused rcd spur fed from indoor socket through wall to Ip56 junction box on out side wall
from there swa 1.5 mm burried 500mm in ground for distance of 26mts then terminated in to ip56 2 gang socket

option 2
normal fused spur fed from indoor socket through wall to ip56 junction boxon out side wall from there 1.5mm swa buried 500mm in ground for a distance of 26 mts then terminated in to a 1p56 rated 2 way consumer unit with rcd ( i am lead to believe swa does not require rcd protection )

will these comply with minor works evn though its notifiable
also because of the earth differensal would the the 2 way consumer unit need to be tt and the earth not terminated at the 2 way consumer end from spur

there is no spare ways in db1 and i do not want to disturb ring final circuits and no room to split tails

i would interested to know how other sparks dealing with these sort of jobs

all responses would be gratefully received

Rich

 

[Spudnik]

Option 1 for me.

SWA does not need RCD protection.

 

[tuckermot]

Hi jason
can i go a head and do the work with option 1 even though consumer in house has no rcd !!!!

i am a waiting my inspection with napit and these jobs keep croping up and i can not afford to keep saying sorry mrs jones but to do this job it means a new dual board ect ect for £400

thank rich

 

[TPES]

If you choose option 1 then although the SWA does not need RCD protection im fairly sure the appliances/equipment pluged into your socket outdoors will require it.

You could run in SWA not RCD Protected directly to an RCD incorparated IP56 Double socket.

 

[tuckermot]

Hi magic sid

so as i am using swa i can use method 1 even though ccu has no rcd ???.Do you come against jobs like this and do you do it this way to ??
Rich

 

[xraytek]

Are you allowed to export the earth in this manner on a TN-C-S system?

 

[TPES]

If you feed in SWA its ok that the main CU doesnt have RCD.
As far as i'm aware your ok to export the earth aslong as your not feeding a building that has exposed conductive parts. (Any incoming services or steel frame work).

If this is the case then you will be required to TT.

 

[tigerpaul]

I'd go with option 1. Now, how is the circuit you are tapping into protected? If by an mcb, cant you change that for an rcbo??

You might not need to protect the SWA by rcd, but outdoor sockets you will

Furthermore, as you are altering an existing circuit, I believe you are then taking responsibilty for it. And I'm sure that it is probably T&E chased into walls, less than 50mm deep, no mechanical protection.... it needs 30mA protection anyway.

 

[tuckermot]

Hi just to respond to responsability of the original circuit !!! if i did a normal indoor spur and fed the new spur in trunking i would not need rcd protection so if i am feeding in swa does the same rule not apply ??