Spurring off FCU supply side

[wassupjg]

Hi, apologies for the basic question

In a radial circuit, is it permissable to spur off the supply side of an existing fused connection unit?

As above, 3A FCU is feeding a floodlight, is it okay to spur off the supply side of the 3A FCU to feed a 13A FCU, isolating an outdoor socket?

Cheers

 

[JohnW2]

....

Your attachment hasn't shown as such - can you try again.

The answer to your question depends on cable sizes and the size of the breaker/fuse protecting the circuit concerned. Can you provide us with that information?

Kind Regards, John

 

[wassupjg]

Your attachment hasn't shown as such - can you try again.

The answer to your question depends on cable sizes and the size of the breaker/fuse protecting the circuit concerned. Can you provide us with that information?

Kind Regards, John

Sorry John don't know what happened there, worked when I posted, have edited the OP hope it shows, the main socket circuit has a 20A breaker in 2.5mm T&E, with 1.5mm T&E coming off the 3A FCU feeding the floodlight.

 

[EFLImpudence]

Yes, you can do as you wish but the 13A fuse is neither necessary nor desirable - a double pole switch indoors would be desirable so use a 20A DP switch.

 

[wassupjg]

Yes, you can do as you wish but the 13A fuse is neither necessary nor desirable - a double pole switch indoors would be desirable so use a 20A DP switch.

Much appreciated, is the DP preferred due to the extra 7A of breathing space? And safer as it's isolating the neutral as well as the live where I assume the FCU would only isolate the live in case of a fault?

 

[EFLImpudence]

Much appreciated, is the DP preferred due to the extra 7A of breathing space?

Well, sort of but more the other way round - the 13A fuse is just not needed so why restrict the supply?

There will be fuses in the plugs used.

And safer as it's isolating the neutral as well as the live where I assume the FCU would only isolate the live in case of a fault?

No the FCU is also DP - you just don't need the fuse.

 

[JohnW2]

Sorry John don't know what happened there, worked when I posted, have edited the OP hope it shows,

Yep,it shows fine now.

the main socket circuit has a 20A breaker in 2.5mm T&E, with 1.5mm T&E coming off the 3A FCU feeding the floodlight.

Thanks for that information (which, as I said, wee needed). I won't bother to repeat his answer, since I agree with everything EFLI has written, including the fact that the 13A FCU is not required.

Kind Regards, John

 

[SUNRAY]

All agreed the FCU certainly not required, nor a switch for that matter but something is a very good idea to provide isolation, even if just for ourdoor Chritsmas lights.

 

[ebee]

As Sunray says a DP switch of some kind is a good idea to isolate things outside in case of damage/water ingress or even just to prevent unauthorised use. So either a 20A DP switch or a Switched Fused Connection Unit would fit the bill. If it`s a SFCU then the fuse is not really needed and might confuse someone in future (including yourself over time).