Cable and gland for external power cable Ask questions and find answers to many subjects relating to electrics and electrical work

[GeorgPat]

I would like to get power from an external junction box in order to fit an external light. The cable will run about 5metres. Since I'm not going underground so, I believe I do not need armoured cable and the metal/brass gland.
I am planning to use a normal plastic 20mm gland and a non-armoured cable.
Is the above correct and what cable is required for external use? Can you please provide a part number or link?
Thanks
George

[Mr White]

What is this existing junction box already supplying? (Also what is it fed from?)

[GeorgPat]

I have attached a picture. The existing jb takes power from the house and feeds it into my garage where there is a light and a double socket. I am thinking to take power out from the jb and run a cable across the pipe and then a few metres left, where I will fit a light.

[Mr White]

You must install a fused connection unit first (Fed from the junction box) then you can add what ever you like after that.

The reason is, the supply to the junction box will be protected by a 32A MCB or 30A fuse. You can use 1mm cable to supply your new light and its switch, as it will be electrically protected by the 3A fuse you are going to put into the fused connection unit.

However as it is outside and low down (going up) the cable needs mechanical protection, for that I would suggest you use black PVC conduit.
Black PVC conduit is made for external use.

You can get everything you need online.
I would suggest toolstation, screwfix or TLC

[GeorgPat]

Great thanks a lot,
I now understand however would you be able to confirm regarding the fuse?
I believe you are suggesting to fuse the branch that I will make for the light and I guess this will be inside the jb. Can you please suggest a part/description for this fuse solution? Should it be only the live wire or the neutral too? I am imagining that will be an inline fuse holder.

Thanks Again

[Mr White]

If / when my car goes wrong, I can use the internet to find out what is wrong, but I know I do not have the skills or right tools to carry out anything other than a minor repair.
You are in a similar boat to me, except your assumptions, although they are in good faith, are wrong and dangerous. It is for those reasons I recommend you get a competent person to do the job for you. The "problem" if you will is that electricity has no prejudices, it will kill anyone, and just "because it works" does not mean it is safe, it needs to be tested with the correct test equipment to prove it is safe.
I am sorry it is not the answer you wanted, but I would rather you are able to ask another question in the future than to find you were killed by ignorance.