power in shed

[fatbloke]

I have a shed with power to it. From the power, which has its own feed from the fuse box, currently is running a single socket and two lights.

I now have a second shed, next to the original. I wish to how a socket in each shed, as well as lighting. How I do do this in terms of circuits?

 

[Damocles]

more information is needed. What is the current rating of the existing power supply to the first shed, what is the cable size, is there a second consumer unit in the shed which then has separate breakers for the light and the socket? Important...is there a RCD somewhere protecting this?

Is this a posh affair where you use lots of electricity for your home workshop and electric heating, or just something to plug in the odd electric drill or radio?

Similarly, do you need lots of power in the new shed, or just a light? You have a choice of wiring everything by the book, or just plugging in an extension lead from the first shed. (don't tell anyone I said that)

 

[fatbloke]

From what the label says in the fuse box in the house, it is a 16a supply to the shed. I have no idea on the cable size (how can I tell this?) There is a fat black cable that comes into the shed.

The current setup seems to be a cable into a triple light switch, running one internal light for the shed, and one external light. The third switch does nothing as far as I can tell. From this socket, a cable runs to a fuse box and then to a socket. There is a RCD in the garage for the cable to the shed.

As for what I require, I want the following:
shed 1: 1 double socket, 1 light internal, i light external (based on existing setup)
shed 2: 1 double socket, 1 light
additionally, if extra for outside lighting could be added, then all the better. Just talking simple garden lighting here, not major floodlights.

It is not to be a "posh affair". All the power would be used for is lawn mower, drill, radio etc. Nothing of major power consumption. However I would like to do it by the book, or near to it as I can.

 

[fatbloke]

Please, has anyone got any advice?

 

[breezer]

still more infopr required, i am worried about size of cable, you have 2 choices

put in new cable of known size

get an electrician (but get several quotes)

 

[fatbloke]

Sorry if I am sounding stupid, but how can I tell the size of the cable? Are we talking diameter of the cable core?

 

[breezer]

its actually the area of its cross section, and no i do not think you are being stupid, you are just unaware, and are asking

 

[ban-all-sheds]

its actually the area of its cross section

Which of course is easily calculated from the diameter...

Another thing - what is the total distance of the cable run twixt CU and furthest point?

 

[fatbloke]

ok. So I need to take the cross section of the cable entering the shed. Then work out its area. I take it that the cross section is of the actual metal core, and not the insulation covering.

 

[ban-all-sheds]

ok. So I need to take the cross section of the cable entering the shed. Then work out its area. I take it that the cross section is of the actual metal core, and not the insulation covering.

Yup - we need to know the csa (cross sectional area) of either the live or neutral conductors - std sizes are:

1.5mm²
2.5mm²
4mm²
6mm²
10mm²
16mm²

 

[fatbloke]

I have had to wait to the weekend to be able to investigate. From what I have discovered today, the wiring was not as I originally thought. There is a cable from the main fuse bos in the house, with the diameter of the live cable being 2-3mm. The cable from fuse box to shed is around 15m in length. The cable enters the shed, and goes straight into a fuse box. I have checked the fuse box, and in here is a 15A and 5A fuse. From the fuse box, there are two cables, one for the lighting, and one for the existing double socket.

 

[securespark]

Some twin & earth cables have the size stamped on the sheath. Can you see anything?

 

[Damocles]

To check, you are still saying the cable from the house has conductors of diameter 2-3mm, which means cross section area between 3 and 6 mm2. this is contained inside a thick black cover, incorporating wire armour? how many cores are there?

next, how far is it to the next shed, will you have to dig a trench or is it just a matter of going straight through the walls?

 

[fatbloke]

Yep the cable is as you described. I think it has 3 cores. Would need to check. As for the new shed it is next door, so just a case of drilling through.

 

[Damocles]

I think we have gathered there is a 16A mcb and a separate RCD in or near the main house consumer unit which is in your garage. From there an armoured cable with cores at least 2.5mm squared goes underground to your first shed and enters a fusebox, with fuses. One 15A fuse powers some sockets. One 5A fuse powers some lights. The second shed is right next to the first. please correct if any of this is wrong.

Ok, so is it possible to run cables directly through the walls of the sheds without a gap, or would cables have to go through the air crossing between them? Are the two sheds either both securely fastened to the ground, or to each other, so that they can not move and pull apart any cables running between them? It sounds as though you can just run some extra cables from the first shed to sockets/lights in the second. They need to be protected if the sheds are separated.