Adding an outside socket.

[JamesHughes]

Hello all,

what I want to do if have a waterproof socket outside the back door, for a temporary supply to the garage, and for general garden implements.

I was thinking of the MK Masterseal RCD protected twin gang (Toolstation 18191) for the exterior on a spur from a socket inside, which is already a spur (so I would end up with 4 sockets on the spur).

What I would also like to do is have a neon switch inside the house, so I can isolate/turn off the exterior socket as required. The only switches I can see are 20A neons (toolstation 64900). Would these be OK to use on a spur to a twin gang socket - as they would add up to 26A max load, more than the rating of the switch. Which sounds wrong.

Should I be doing this a different way?

TIA for any advice.

James

 

[breezer]

you should not spur from a spur, and temp supply to garage sounds bad

as my late father used to say "there is nothing so permanent as a tempory job"

he also said "ahhhhhhhhhhhhhh" then he died but thats not the point

 

[JamesHughes]

Just to clarify, the temp supply is just to feed an extension lead to garage until I get a three phase suppy put in(waiting for funds to accumulate!). At the moment the lead has to go through a window!! Brr.

Ok, on the spur off spur, that means I presume that I need to extend the ring main so that the the interior socket is ringed, and then I can spur off it. Or I make the spur to the exterior socket go to a ringed socket in the first place. That's probably an easier job. I think there is a accessible ringed socket in the next room, and the location of the exterior socket is up for grabs really.

Ta.

James

 

[ban-all-sheds]

So is your existing ground floor socket circuit not RCD protected?

 

[JamesHughes]

I thnk it is actually - there is a 'bolted' on RCD on the consumer unit.

(Yes, I know this little lot needs replacing!! When the garage gets its 3-phase I get a new CU as well)

I guess from your question that if the ring has an RCD then I dont need one on these outside sockets? That would make it a lot cheaper.

James[/img]

 

[Chri5]

No the only circuit having RCD protection is the shower circuit.

Ideally you should have a split RCD board with all g/f ring and external stuff via the RCD.

I think adding to the existing aged installation is a false economy and your better off putting the ££'s towards up grading the CU etc sooner rather than later.

If you really MUST do things now (and then change them later when 3p and new CU required):-

Provide a neon switched 13 a spur from the ring, use the load side to wire to the external RCD protection IP6 rated double socket.

These sockets aren't that good, the RCD and general design doesn't wear well hence why I have suggested RCD on the CU and that would save £30 on the external socket being a simple unit rather that with intergrated RCD.

 

[ban-all-sheds]

Or make the spur an RCD one, because that could potentially be reused to put the bathroom circuits on an RCD if you wanted to go that 17th route and not have supplementary equipotential bonding...

 

[JamesHughes]

Hmm. Looks like its not worth doing the outside socket until I replace the CU, but I guess it means more money to the CU fund! I'll live with having to put the extension through the window for the moment.

As an aside, I have not found anything in the house that the left hand box actually turns off, so I reckon that can be dispensed with - I think it must have been for the Economy 7 circuits to the storage heaters which is why the house has a 3PH supply in the first place. All removed before I moved in, bar the CU and one errant socket which only works in the middle of the night!!

Thanks for the advice all.

James

 

[ban-all-sheds]

Funny - I was just about to observe that you've got an awful lot of 15A circuits there...

 

[plugwash]

As an aside, I have not found anything in the house that the left hand box actually turns off, so I reckon that can be dispensed with - I think it must have been for the Economy 7 circuits to the storage heaters which is why the house has a 3PH supply in the first place. All removed before I moved in, bar the CU and one errant socket which only works in the middle of the night!!

If you are a bit short on sockets and the storage heater wiring is still in place (ending at unused switches or outelet plates or whatever) you might want to consider repurposing it as socket wiring.

 

[securespark]

Or make the spur an RCD one, because that could potentially be reused to put the bathroom circuits on an RCD if you wanted to go that 17th route and not have supplementary equipotential bonding...

Got some bad news for you, Ban, and others who think it's OK in all cases to do away with supplementary in a bathroom if everything in it is RCD-protected.


The DPC did say you can do away with supplementary if:

1. you have all circuits 30mA RCD-protected, and

2. If you have MEB's to all services etc.


It may be OK still to omit SEB, but the final regs have changed from the DPC:

Quote:

In a building with a Protective Equipotential Bonding system in accordance with 411.3.1.2, supplementary EB may be omitted where all of the following conditions are met:

1. All final circuits of the location comply with the requirements for ADS according to 411.3.2.

2. All final circuits of the location have additional protection by means of an RCD in accordance with 701.411.3.3 (ie 30ma / 40ms at 5x)

3. All extraneous conductive parts of the location are effectively connected to the PEB according to 411.3.1.2.

Note: The effectiveness of the connection of extraneous conductive parts in the location to the main earthing terminal may be assessed, where necessary, by the application of 415.2.2.


415.2.2 (in part)

Confirm that the resistance between simultaneously accessible exposed conductive parts and extraneous conductive parts fulfills the following condition:

R is less than or equal to 50 V/Ia,

where Ia is the operating current of the protective device:

for RCD's, I delta n.

for overcurrent devices, the current causing automatic operation in 5s.

 

[briwire]

Inside your house, use a fused switched spur with neon instead of a 20A switch. That way you can't take any more than 13A from your ring.

 

[Chri5]

Provide a neon switched 13 a spur from the ring, use the load side to wire to the external RCD protection IP6 rated double socket.

.

 

[ban-all-sheds]

Or make the spur an RCD one, because that could potentially be reused to put the bathroom circuits on an RCD if you wanted to go that 17th route and not have supplementary equipotential bonding...

Got some bad news for you, Ban, and others who think it's OK in all cases to do away with supplementary in a bathroom if everything in it is RCD-protected.

I don't think that.

When I said "the 17th route" I had in mind the situation where all of the relevant requirements of the 17th would be adhered to, not just the subset of "put everything on an RCD and get rid of SEB"....