Flex Cable size vs Twin & Earth size
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The socket fed via 2.5mm will be protected by a 20 or 32amp MCB, the multiway socket by a 13amp fuse, in the plug(top).
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!.5 mm² 2.5 mm² 4 mm² and even 6 mm² can be used to wire a socket, over 6 mm² unlikely to get it in the terminals, the size used is selected based on the volt drop and the protective device. We want with a short circuit for the protective device to open, be it a fuse, MCB, or RCBO. And also for the wire not to melt.
So in the main we use 1.5 mm² for extension leads, however with caravans for example which are only 16 amp rather than 13 amp, we still use 2.5 mm² because of the volt drop with a 25 meter cable.
2.5 mm² is good for around 20 amp but it does depend on insulation method, but a ring final is fed from both ends, so one should not have over 20 amp in the cable even when feed from a 32 amp overload.
Radials can be wired in 4 mm² and still use a 32 amp overload, however to ensure the overload trips ring final limited to around 106 meters and a 4 mm² radial around 35 meters, mainly due to volt drop, and keeping it to 5%.
A spur is limited to 26 amp (double socket) but it is considered unlikely both would have full 13 amp for an extended time, so permitted, two single sockets are not permitted, The fuse in plug limits it to 13 amp per outlet, use a fused spur and you can have as many as you want as the 13 amp fuse in the FCU limits the load.
So in the main we use 1.5 mm² for extension leads, however with caravans for example which are only 16 amp rather than 13 amp, we still use 2.5 mm² because of the volt drop with a 25 meter cable.
2.5 mm² is good for around 20 amp but it does depend on insulation method, but a ring final is fed from both ends, so one should not have over 20 amp in the cable even when feed from a 32 amp overload.
Radials can be wired in 4 mm² and still use a 32 amp overload, however to ensure the overload trips ring final limited to around 106 meters and a 4 mm² radial around 35 meters, mainly due to volt drop, and keeping it to 5%.
A spur is limited to 26 amp (double socket) but it is considered unlikely both would have full 13 amp for an extended time, so permitted, two single sockets are not permitted, The fuse in plug limits it to 13 amp per outlet, use a fused spur and you can have as many as you want as the 13 amp fuse in the FCU limits the load.
What is this multi-way socket?
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If you mean one of these
The product is protected by the 13 amp fuse at the wall. If you plugged in a washing machine, vacuum cleaner and microwave, and tried using them all at the same time, all that would happen is that the fuse would blow. Hence 1.5mm is Ok
The product is protected by the 13 amp fuse at the wall. If you plugged in a washing machine, vacuum cleaner and microwave, and tried using them all at the same time, all that would happen is that the fuse would blow. Hence 1.5mm is Ok
in the plug (bottom)!!
and bottom to you!
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It’s one of these:
Masterplug ELS134B-01 Permaplug Four Socket Trailing Socket with Power Indicator, without Plug and Cable, 13 Amp, Black https://amzn.eu/d/99oaYcV
I suppose you could call it a trailing socket, I’ve always called it a multi way socket as I’ve no idea what they should be called!
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