• IMPORTANT: The thread you're reading / posting in, could be in a DIY electrical advice area. Please be aware of your local laws. You're not allowed to provide advice to, or seek advice from, DIYers and fellow professionals in some States, Countries, Countys etc with regards to some types of electrical installations or repairs. Keep that in mind. If it's against the law where you are - always get a professional electrician in to carry out the works instead of doing it yourself. The forum will not be held responsible for any outcome of any applications of any advice sought from it.

Discuss Outdoor socket used as junction box in the DIY Electrical Forum area at ElectriciansForums.net

Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:  American Electrical Advice Forum

Hi,

I am currently building a new outbuilding in my garden to be used as an office which will end up having a reasonable amount of power usage (Heating, multiple computers, lighting and a few other bits and bobs) and I am looking at reusing a power feed that previously ran to a shed which was removed for the build. The armoured cable looks to be 8 core and from what I can tell should be more than up to the job.

The cable runs buried then up out of the ground to an outdoor RCD socket and a second length of cable also connected into the socket from back into the ground over to where I am constructing the office. The sockets are fairly inaccessible so I assume it was used as a junction box of sorts.

My question is, is that acceptable or should that really be replaced with a junction box?

Thanks!
 
Electrical2Go - Online Electrical Supplier
This official sponsor may provide discounts for members

Spoon

-
Mentor
Arms
Esteemed
Welcome to the forum mate.
What does the 8 core SWA cable connect to at your house?
As above, take pics of your house CU, 8 core SWA cable & outside socket.
Do you still use the outside socket?
See if there is any info of the 8 core SWA cable marked on the cable.
Measure the diameter of the cable and the wires and let us know.
Also need more info on what is cable is actually going to power. Give us a list of all equipment.
 

Pete999

-
Arms
Esteemed
Couple of questions:
What size is the cable feeding the "outside socket/junction box"?
What size is the cable coming from the OSS/JB to your new build?
Have you any idea what the load will be required by your office?
No more question, you really as others have said need advice from someone who is competent, it may well be that you will need a new supply, as you have said the cable looks to be ample for the job, what leads you to that conclusion?
 

davesparks

-
Mentor
Arms
Esteemed
Since its multicore it could be that someone has extended a ring circuit from the house to the external socket.
I don't think it would be very sensible to extend this to the new outbuilding, and definately not by the method proposed in the OP.
 
I think others have already said - get an electrician - if it’s going to be used for heating, power, lighting - proper office outbuilding, it may need a supply direct from the fuse board on its own supply and mini board - again, professional advice is really needed here and that can only really be done by a visual inspection of the current set up.
It may also involve local building control due to the nature of the works. An electrician would be able to do this for you if they are registered with a professional body as part of the work....
 
  • Thread Starter Thread Starter
  • #12
Hi all, thanks for your replies. I should have included some pictures to get started with, I should have thought that through. I should not have decided to write the post at 3am, by 8 core I was referring to the strands within the cable which is largely irrelevant and not quite sure why I bothered to write that, what I should have said is its 2 core 4mm cable. I am certainly not stupid enough to mistake cat 5 for armored cable ;) From my understanding the 4mm cable has a 40+ amp rating and should be enough to run the outbuilding from without having to dig up the entire garden which would be good to avoid, but I am happy to be corrected!

Equipment running within the office will be two computers, 5 monitors, led lighting and an electric panel heater (Which will most likely be a 1000w model).

The reason I am asking about how the plug is wired is to me it seems an odd way to do it but given the previous owner of the house (claimed) to be an electrician I wondered if there was reason behind it or it was just some quick hack. The plug is not in a useful place and can be replaced with a junction box happily if that is a better approach. Prior to turning off the outdoor circuit the plug was in working order as were the plugs within the shed which has now been removed. The plug is not easily reached as its nested away behind a bamboo plant but it is an RCD outdoor switch which resembles the attached picture. Also attached is a picture of the cable and where it connects up in the garage.

ae235.jpg

Cable.jpgConnection.jpg
 

Spoon

-
Mentor
Arms
Esteemed
The Crabtree CU already has a RCD for the circuit, so not sure why the socket has RCD as well.
Is the cable connected to the 16A breaker?
What does the 10A RCBO connect to?
They are both turned off.
How long is the run to the shed from the house?
 
  • Thread Starter Thread Starter
  • #14
The Crabtree CU already has a RCD for the circuit, so not sure why the socket has RCD as well.
Is the cable connected to the 16A breaker?
What does the 10A RCBO connect to?
They are both turned off.
How long is the run to the shed from the house?
The cable is connected to the the B16, the B10 is connected to some underfloor heating in the kitchen. Both of which as you say are turned off and have been for some time. The run is 25m.
 

Spoon

-
Mentor
Arms
Esteemed
Is the second cable from the outside socket to the shed also 4mm SWA?
Are there any extraneous parts in the shed?
 
  • Thread Starter Thread Starter
  • #16
Is the second cable from the outside socket to the shed also 4mm SWA?
Are there any extraneous parts in the shed?
Thanks for all your replies, really appreciate it. Yeah, the full run from the garage to the socket and from the socket to where the office is being built is all 4mm SWA. The shed is no longer there the cable in the picture is where it currently surfaces and if sufficient is what I hope will be connected into the office.
 
  • Thread Starter Thread Starter
  • #23
and me... @henry, are to measuring the diameter of the copper to get 4mm?
Yeah, sadly I did - I had it written down from a while back and did not recheck. I've just been back out with some calipers and the dia is 4mm, with each strand being 1.4mm, roughly working out to be 11mm2. No markings on the cable other than brand, date and BS number. Good spot @westward10 and @telectrix
 

Matthewd29

-
Arms
Esteemed
That looks bigger than 4mm, and 4mm probably won't be rated at 40a+ once you do your calculations at any distance. As well if you do take on this work yourself make sure it is glanced correctly if you are using the armour as the earth, again providing calculations are satisfactory.
 
T

Toneyz

You need to confirm what the cable is to the socket and from the socket to the shed as I can't see how you can connect two 10mm cables in the socket terminals. A bit more investigation of what is behind covers.
 
  • Thread Starter Thread Starter
  • #27
You need to confirm what the cable is to the socket and from the socket to the shed as I can't see how you can connect two 10mm cables in the socket terminals. A bit more investigation of what is behind covers.
I measured the diameter at 4mm previously and had it written down, I had not worked it out to mm2, after remeasuring/calculating(as it is not marked on the cable) it is 10mm and is the same running from the garage to the socket and from the socket to where the shed was. I have just taken the socket apart and whoever did it basically clipped the wires to a taper so they would fit, and poorly at that. No idea who did it or why but there is no way I am going to use that again so no matter what now I think it is best to get rid of that and have it replaced by a proper junction box.

That looks bigger than 4mm, and 4mm probably won't be rated at 40a+ once you do your calculations at any distance. As well if you do take on this work yourself make sure it is glanced correctly if you are using the armour as the earth, again providing calculations are satisfactory.
If I do, I will - thank you for your advice!


Thanks to everyone who has posted constructively, especially @Spoon for taking so much time out of your day to reply and those of you who helped me unmuddle the wire sizing!

I have some time before this needs to be done and if at any point I am atall uncertain I will make sure to get a qualified electrician in to do the job.
 

davesparks

-
Mentor
Arms
Esteemed
I suggest that the next sensible step is to get an electrician to inspect and test those cables to ensure they are suitable for continued use, and also check the size.
If the cables are of a suitable size and in good condition then get the electrician to advise on the rest of the job and quote to do it properly.
I would suggest that the socket he removed and the SWA jointed in a cast resin type joint.
 
Electrical2Go - Online Electrical Supplier
This official sponsor may provide discounts for members

Reply to Outdoor socket used as junction box in the DIY Electrical Forum area at ElectriciansForums.net

Top Bottom