Ring main consisting of only spurs

[Pete999]

Old imperial cable has a greater cross section than 2.5 mm cable

An "old" installation with a ring around the top floor and spurs down to the socket below means each socket will have 3 cables

Therefore the sockets need to accommodate 3 x 4mm cables .... as they are very unlikely to accept 3 x imperial cables ...

Dead easy to get 3 times 7/029 into a socket terminal, now 7/036 or 7/044 would be different 7/029 easy peasy. Remember 7/029 is stranded, 4mm2 is solid, and 7/029 is the closest Imperial size to 2.5mm2 cable, 3/029 would be to small 7/036 = aprox 4mm2

 

[telectrix]

worst thing was with the 7/029 was muppets twisting 3 cables into a demented corkscrew then forcing into a terminal that would only just accommodate them. usually by snipping a few strands off.

 

[Toneyz]

When I started out all the sockets had a nice large bellmouth terminals Contactum for one.

 

[telectrix]

yep.they were 15A round pin jobbies. built like a brick shiithouse. never any poor contacts ( and you could wedge wires in with rawlplugs),

 

[Pete999]

worst thing was with the 7/029 was muppets twisting 3 cables into a demented corkscrew then forcing into a terminal that would only just accommodate them. usually by snipping a few strands off.

Agree, but done carefully you could manage ti get three in a terminal on a socket

 

[ipf]

Not quite the same, but I remember wiring a council office, two large downstairs flats knocked into one, concrete shell with suspended ceiling . Wired it to spec....and then they changed it all, offices and large kitchen. Trouble was, they wouldn't let us rewire because it was mostly ready for 2nd fix. There were loads of socket points all to be moved. Broke into the ring at every point and fitted 2 x 30 amp JB's. There must have been fifty odd JB's on four rings, all Clerk of Works approved.
Never any comebacks, though.

 

[Timbo]

My senior lecturer at college in late 80's always propounded that theory. He was going to rewire his bungalow like that. He said a jb was no different from having a socket in the same location.

 

[Octopus]

My senior lecturer at college in late 80's always propounded that theory. He was going to rewire his bungalow like that. He said a jb was no different from having a socket in the same location.

Except you wouldn't have sockets under the floor...

 

[Timbo]

He didn't have a floor in his roof