If i've got a light with one cable, and its switch has one cable, how is it wired?

[rewireIT]

A switch i saw today has a T+E in the switch and only a single T+E in the light fitting.

I'm presuming this means it's junction boxed somewhere?

Could someone point me in the direction of a potential diagram for such a set up?

 

[westward10]

There could be multiple scenarios to explain this, one being a junction box mirroring what you would normally expect to see at a batten holder or ceiling rose.

 

[rewireIT]

There could be multiple scenarios to explain this, one being a junction box mirroring what you would normally expect to see at a batten holder or ceiling rose.

I was imagining a 4 terminal JB with L N E and SW in.

T+E comes from L + SL + E to the switch, then a second T+E comes from N + SL + E to the fitting.

Is that far off?

 

[Taylortwocities]

All you need to know is here:

Lighting Circuits using junction boxes

Details of wiring UK lighting circuits using junction boxes

flameport.com

 

[Loki]

Lightwiring.co.uk has good info

Old multi-point radial lighting diagram using junction boxes

Fig 1 shows what is referred to as a radial circuit (sometimes called a 'loop-in' or 'multi-point radial lighting circuit'). which uses junction boxes instead of ceiling roses. You may find this wiring arrangement in older properties.

www.lightwiring.co.uk

Also you could find that connectors are pushed up into the ceiling & they have just brought down a single T&E.

 

[Taylortwocities]

Back in the distant past, domestic lighting circuits used humungeous junction boxes where all of the switches and light fittings joined. Usually there was one hidden under the floor of the landing / for the ground floor lights. The upstairs box was in the loft.

Known as Octopus boxes. They were such fun. Here’s an example

Another type

 

[rewireIT]

Back in the distant past, domestic lighting circuits used humungeous junction boxes where all of the switches and light fittings joined. Usually there was one hidden under the floor of the landing / for the ground floor lights. The upstairs box was in the loft.

Known as Octopus boxes. They were such fun. Here’s an example
View attachment 109508
Another type
View attachment 109510

What era are we talking?

 

[telectrix]

Back in the distant past, domestic lighting circuits used humungeous junction boxes where all of the switches and light fittings joined. Usually there was one hidden under the floor of the landing / for the ground floor lights. The upstairs box was in the loft.

Known as Octopus boxes. They were such fun. Here’s an example
View attachment 109508
Another type
View attachment 109510

is the top pic. lead sheathed cable, with them being clamped with a metal cpc band. If so, I'd age that 1920s - 30s.

 

[Taylortwocities]

What era are we talking?

Most of 20th century up to about mid 1960’s. You’ll notice from the pix above that no earth is provided and that wasn’t introduced for lighting circuits until 1966.
At that point (I guess) an Octopus became unwieldy as you might have a large number of earth wires to common up in one box.
What seems to have happened is that electricians took to the round junction boxes. These were mostly 3-terminal, leaving no place for the earths but the sparks used to just twist the earths together outside the box!

This often meant one box per light. Ceiling rose junction boxes had been around since 1914 and I expect that at around this point, some brainbox expanded it to include the loop in connections that we all know and love.

 

[telectrix]

but back in the day, early 20th c,. relative to my last post. cpc was the lead sheath . can't beat the old ways. bring back steam engines - burn wood and coal. male the stop oil terrorists happy. not to mention scargill.

 

[Dustydazzler]

If there is just a single cable at the light, first thing to check for is if a handful of connector block isn't shoved in the ceiling or in the call just above / behind the light. Very very common to find this in domestic settings

 

[rewireIT]

If there is just a single cable at the light, first thing to check for is if a handful of connector block isn't shoved in the ceiling or in the call just above / behind the light. Very very common to find this in domestic settings

As someone who does commercial it baffles me how some housebashers do it

 

[Dustydazzler]

As someone who does commercial it baffles me how some housebashers do it

If you spent a month with me going round relatively new houses putting rights some terrible shoddy installs you would be horrified what some Domestic sparks do...

 

[littlespark]

You shouldn’t suggest all domestic sparks are rough. I’ve seen quite a few bodge ups in industrial that would make your eyes water.

“Housebashers” by definition rush through jobs as that’s all the time they have because their company priced low to win a job. Every trade on a development does exactly the same.

There’s good and bad in all fields.