From old alarm to front light

[Orlgo]

Hi,
I have recently removed an old wired house alarm system that was totally defunct. Only the electrics to the control box were active, and as far as can be seen, this is spurred off the ring main under the first floor floorboards, I know not where or how. Only by isolating this ring was it possible to ascertain the power source, however, restricted access due to decor etc, make it virtually impossible to trace the cable back.
With this single cable being taken from the upstairs ring main, is it possible for me to utilise it to power a front door outside light, through a fused socket? If so, what rating would this socket have to have, and would I need to fit a 5 amp fuse to it? Any advice would be greatly appreciated, thank you

 

[EFLImpudence]

There are no fused sockets.

Are you thinking of (switched) Fused Connector Unit?

Yes you can use one of them, also as a switch.
A 3A or 5A fuse will be sufficient.

Ideally the cable/circuit should be tested.

 

[ericmark]

It is permissible to fuse either at origin or destination if the cable is unlikely to be damaged and less than 3 meters long. So one can only guess what cable is used and what protection, however for say a 10W outside lamp one is hardly likely to cause a problem, I would say fit same size fuse as fitted in the alarm or smaller and it will likely be OK.

 

[ban-all-sheds]

... less than 3 meters long ...

Eric, please stop this, it isn't true.

 

[Orlgo]

Many thanks guys, I do appreciate your time and effort in replying