FCU's and Spurs

[techno492]

2 questions for you very knowledgeable people...


1) Is it acceptable and safe to take a switched FCU from a double socket that is already a spur its self and connect a <5A outdoor light to it ?
(Fuse in FCU will be 5A)

2) Again is it acceptable and safe to take a switched FCU from a double socket that is part of a ring but also powers a double socket as a spur and agan connect a <5A outdoor light to it ?
(Fuse in FCU will be 5A)
This double socket is in a totally seperate room to the one proposed in question 1

Thanks

 

[JohnW2]

1) Is it acceptable and safe to take a switched FCU from a double socket that is already a spur its self and connect a <5A outdoor light to it ? (Fuse in FCU will be 5A)

If, as I suspect, you mean that the existing socket is an unfused spur (i.e. not connected via an FCU), then the simple answer is No. Spurs from unfused spurs are not allowed.

2) Again is it acceptable and safe to take a switched FCU from a double socket that is part of a ring but also powers a double socket as a spur and agan connect a <5A outdoor light to it ? (Fuse in FCU will be 5A). This double socket is in a totally seperate room to the one proposed in question 1

Many people will say that it is 'not good practice' to take two spurs from the same place, but there are no regulations which explicitly forbid it. In electrical terms, it's not appreciably different from taking spurs from two sockets on a ring which are physically right next to one another. Particularly given the small load you are talking about, I would not personally be worried about doing as you suggest. Getting four sets of conductors into the socket's terminals may not be easy (and may exceed what the manufacturer says is the 'maximum (physical) capacity of the terminals.

Kind Regards, John

 

[ericmark]

Acceptable no as to safe that's another question. The problem is many sockets will take three cables per terminal but squeeze in a forth and there is a chance one will not be gripped in a manor able to take the power without overheating.

So in general we will not put more than three wires in a terminal.

The other is the overload problem a B32 MCB will provide more current than 2.5mm² is rated for at two sockets 26A is still likely an overload but not enough to really worry about.

 

[JohnW2]

Acceptable no as to safe that's another question.

I'm not sure I understand that statement, at least as a generalisation. In the absence of any specific/explicit regulations, if it were safe, it would be 'acceptable' reg-compliant), wouldn't it?

The problem is many sockets will take three cables per terminal but squeeze in a forth and there is a chance one will not be gripped in a manor able to take the power without overheating.

Indeed, I acknowledged that issue, and indicated that it might exceed the maximum cable capacity specified in the MIs.

The other is the overload problem a B32 MCB will provide more current than 2.5mm² is rated for at two sockets 26A is still likely an overload but not enough to really worry about.

I agree with the facts you state, but I don't really see what that has got to do with taking two separate spurs from the same point of origin.

Kind Regards, John