Any electricians on here?

[simonjrwinter]

I have a query about armoured cable for a summerhouse….
Simon

[StewbieC]

What's the question?

[simonjrwinter]

I’m putting in a 16mm3 armoured cable to provide power for my summerhouse which is about 75 feet from the house. The cable will enter the house in the ground floor void then it has another 35-40 feet to travel to get to the consumer unit.
Is it safe/legal to join the armoured cable (with a suitable junction box of course) inside the houser and complete the run to the consumer unit in an equivalent cable only non-armoured.
I’m asking because the route to the consumer unit is pretty convoluted and getting an armoured cable along this route will be nearly impossible!
Simon

[StuBaker]

I guess you mean '16 mm diameter 3 core' ?
This will be 6mm sq ? Depending on your measuring it could be 4mm sq.?
There's a bit more to it I'm afraid.
What load are you putting on it?
It's a long run so make sure you fit the correct breaker.
It will also need testing.
You can do the donkey work laying the cable.
Get a 'Leccy in, they're nice guys really.

[simonjrwinter]

This stuff …… https://www.screwfix.com/p/prysmian-694 ... drum/604rk
16mm2 conductor area (sorry, got my terminology awry)
I am having it connected up by an electrician with everything done to the correct spec
Just need the question above answering

[cobraboy]

Why don't you ask the guy that is connecting it up - The electrician ??????

[simonjrwinter]

It’s a pal of mine who’s dealing with some personal issues at the moment. Didn’t want to concern him with trivial things

[cobraboy]

Ah fair enough
The reason I said ask him is, my experience with electricians is, there is more than one way to do a correct job. The guy doing the install will have his preferences and may give you a go, or no go, on what you are wanting to do.

[StuBaker]

That's a relief, how the cable is installed affects its rating. Its 4mm conductors.

[StewbieC]

Size of the cable depends upon what it is being fused and length it is being laid which determines voltage drop can be looked up in cable tables. The distances you are talking shouldn't be an issue really.. I would see no issue with it being joined. Every cable in a ring main is joined at each socket. I last did 16th edition which was some time ago. For a summerhouse unless you are planning on fitting loads of electric heaters the cable you are planning should be plenty (if not a bit heavy). It would be best to check and if he would prefer the armoured laying in conduit, grit or sand (or just in soil) as he will be signing it off. I've always ran mine in soil and never had any issues. 3 core is best, people used to rely on the armour as the earth.
If I were doing that job for myself I'd use 6mm2 3 core SWA, lay it in the soil and have no issue fusing it at 32A. It will be plenty for a summer house. I'd fit a small breaker board in the summer house and fit a 6A breaker for lights and a 16A for sockets.If I were laying a slabbed path I'd lay the cable about 10" under the path. It just offers a bit more protection from accidental pick axes. All of my armoured Cables are terminated (I just use standard BW glands ensure the gland cover is cut so it's snug on the cable and I've made off hundreds in my life up to 240mm2) in boxes and I run T&E to the board inside the house. I don't do work for others anymore as I don't have the time. Check with your electrician just in case he has other ideas. All comments are JMHO