External Power Advice....

[Crossed Wires]

Hello One and All,

I have a conondrum in regards to adding some external power. Specifically I have a pond which we have a pump/filter combined so just one cable for this, the device has a 10m cable and I also have conduit to bury it in. I also have an external double power socket which I'd like to add too.
So on an external facing wall I currently have a single power socket and next to it the previous owner has placed an FCU which feeds a sensor patio light on the inside of that wall. So what I want to do is drill directly through the back of these to feed the sockets on the outside wall.
Now this is where I'm a little confused with what's required....
Am I able to spur off of the single socket or FCU to then place an external RCD which the pump cable will be connected?
Then from the side of the RCD am I able to do a short covered cable to supply the external double socket?
The RCD I had seen was this...
http://www.screwfix.com/p/bg-13a-switched-weatherproof-rcd-fcu/20523
With this double socket...
http://www.screwfix.com/p/lap-13a-2-gang-dp-switched-plug-socket-with-outboard-rocker/30139

Answers on a postcard please....

Thanks
Alex

 

[winston1]

Is your socket circuit already protected by a RCD? If so you don't need or want another. Whether you can spur off the inside socket depends on various things. If it is already a spur on the ring you cannot. If it is part of the ring you can.

 

[Crossed Wires]

Thanks - the mains goes back to the CU but it's an old one (fuse wire) so I'd imagine it would be wise to place a modern RCD on the pond pump.
I need to check, my guess at the moment is that the single power socket in the living room is in the main ring but the FCU for the patio light was a later addition and I'd expect that to be spurred off of the single socket.

 

[ban-all-sheds]

I also have conduit to bury it in.

What type of conduit?

How deep will the cable be buried?

 

[Crossed Wires]

It's heavy gauge conduit, it'll be buried around a foot and a half down with the patio being replaced above it.
The pond itself is only about 3 metres from the house at that point.

 

[ban-all-sheds]

Unarmoured cables buried in plastic conduit do not comply with the regulations.

 

[mwatsonxx]

Unarmoured cables buried in plastic conduit do not comply with the regulations.

Wrong, they do comply.

 

[Crossed Wires]

Did I say it wasn't armoured cable?

Besides - as important as that is, I know where I stand with that. It's not the point in my query

 

[ban-all-sheds]

Wrong, they do comply.

And 522.8.10 says what, exactly?

 

[JohnW2]

Did I say it wasn't armoured cable?

You didn't - but if it were armoured, then you wouldn't actually need the conduit.

Besides - as important as that is, I know where I stand with that.

Fair enough

Kind Regards, John

 

[ban-all-sheds]

Did I say it wasn't armoured cable?

Besides - as important as that is, I know where I stand with that. It's not the point in my query

Well you and watson had better just get on with it, then.

 

[JohnW2]

And 522.8.10 says what, exactly?

It 'exactly' requires "equivalent protection against mechanical damage", but it doesn't appear to say 'equivalent' to what, so I personally find it hard to interpret.

Kind Regards, John

 

[ban-all-sheds]

If you hadn't given up reading half way through the first sentence you would have seen that it clearly says equivalent to "an earthed armour or metal sheath or both".

Not that it matters - the OP knows full well that what he is planning to do is non compliant, he doesn't care, and watson is encouraging him.

 

[mwatsonxx]

Wrong, they do comply.

522.8.10 say - Except where installed in a conduit or duct..........cables shall incorporate an earthed armour sheath.

And stop the insults, they always start when you're wrong. And then go crying to admin to get the evidence removed.

 

[JohnW2]

If you hadn't given up reading half way through the first sentence you would have seen that it clearly says equivalent to "an earthed armour or metal sheath or both".

It's not as simple as you suggest - and, needless to say, I did read the whole sentence.

The rest of the sentence speaks of "earthed armour or metal sheath". If the reg is requiring that the conduit should provide 'mechanical protection' equivalent to the mechanical protection afforded by some 'earthed metal sheaths' (i.e. very little mechanical protection), then any sturdy plastic conduit would probably qualify.

Kind Regards, John