another shed electric question

[pcdee]

Hello all, this is my first post.

I have gone through many posts that are similair to mine but none answear my question.

I have a summer house at the back of my garden about 15m, my CU is at the front of the house. It would be alot easier if I can just extend my ring main as there is one in the back room.

My plan was to spur of the back socket with a SWA cable (3 core 4mm), into a MK IP65 Garage Unit 40A 30mA RCD+1x6A 1x16A SP MCB. Add three sockets to the 16A and then add a fused 3A spur to the 6A for the lights.

if the above is okay what sort of spur will I need for taking of the ring main?

Thanks

 

[Master of None]

I am not an electrician but have read most posts on this forum. So I will have first crack.

As you said you are taking a spur. Not extending your ring final as you quoted earlier.
Max 13A for a spur from a ring final.

If you wanted to go this route I suspect you would have to protect your ring with a 13A FCU. Which means your 16A MCB will be to big. ie fuse will blow first.

Also why have a 3A FCU from a dedicated 6A lighting MCB?

don't worry someone will answer with the science soon.

 

[ban-all-sheds]

My plan was to spur of the back socket with a SWA cable (3 core 4mm),

There's room in there for a SWA gland???

into a MK IP65 Garage Unit 40A 30mA RCD

So is your existing socket circuit not RCD protected?

then add a fused 3A spur to the 6A for the lights.

Why?

if the above is okay

It's not - too much load from one point on the ring final.

what sort of spur will I need for taking of the ring main?

A fused one. Which makes your garage CU pointless.

Still notifiable though..

 

[pcdee]

Thanks for the replys:

We had a sparky come round and suggested CU in the shed, so he can split the load.

The fused 3A spur from 6A is for the light switch, I was told I need to have 3A in the switch.

The current ring main is not protected via RCD.

I would be gratefull if you can recomend another setup, also is the 4mm SWA okay or does it need to be 6mm? Only running a freezer, lights and maybe lawnmower.

Thanks

 

[ban-all-sheds]

Thanks for the replys:

We had a sparky come round and suggested CU in the shed, so he can split the load.

No - you had someone pretending to be a sparky come round.

The fused 3A spur from 6A is for the light switch, I was told I need to have 3A in the switch.

Presumably the buffoon who came round told you that?

The current ring main is not protected via RCD.

So you need to end up with RCD protection on the socket(s) in the shed.

I would be gratefull if you can recomend another setup,

I recommend kicking the incompetent fraudster you had round into touch and getting someone who knows what they are doing.

also is the 4mm SWA okay or does it need to be 6mm? Only running a freezer, lights and maybe lawnmower.

4mm² will be fine for that, but what if in the future you want to run more things out there - would you want to dig that trench again to replace the cable?

freezer

How cold does it get out there in the winter?

 

[pcdee]

Thanks for the reply.

I am basically trying on saving money and have had some wiring experience so I would like to do it myself.

What sort of setup would you recommend?

 

[ban-all-sheds]

I am basically trying on saving money and have had some wiring experience so I would like to do it myself.

We had a sparky come round.

 

[pcdee]

We had a sparky come round.

To give a quote, was quoted £350

I am basically trying to save money and have had some wiring experience so I would like to do it myself.

Would rather save that £350 and do it myself

 

[ban-all-sheds]

What sort of setup would you recommend?

Split the tails - new tails to a switchfuse - armoured cable to the outbuilding - small CU.

This, BTW:

freezer

How cold does it get out there in the winter?

is a serious point - you must check what the lowest ambient temperature is that your freezer will work in.

Would rather save that £350 and do it myself

What's notification going to cost you?

 

[GaryMo]

Would rather save that £350 and do it myself

What's notification going to cost you?

Most of that, the rest being materials. In fact that combo may well end up more than £350!

 

[Roo]

Would rather save that £350 and do it myself

I'm doing something similar.
Parts cost me around £200 plus I had some stuff.

And I've just been quoted £160 for an Inspection of the local council to comply with Part P of the building regs.

I know your not suppose to discuss prices on here but £350 sounds quite good and it's a lot less than my mates been quoted, I'd get that spark back.

 

[Pensdown]

I know your not suppose to discuss prices on here but £350 sounds quite good and it's a lot less than my mates been quoted, I'd get that spark back.

If a spark suggested to me that feeding a CU in a shed from the back of socket in the house was OK, I wouldn't get him back even if he was free.

The thought of trying to test the installation should be enough to put anyone off.

Your money has been well spent.

 

[Roo]

True.

I've got to learn to start reading all the post instead of just browsing through.