Mating with Conduit

[BJC]

I installed mains halogen lights in a kitchen only to find when testing them that the earth was disconnected. On investigation I found that the two light circuits have been rewired in the original steel conduit, with all wires balled in a mass of confusion in a 4" square JB in the loft (turned out the kitchen earth wire was left short in its tube and didn't enter the JB).

Anyway, thought I would tidy the whole thing up by getting rid of most of the conduit except the light switch drops and also separate the two circuits into their own JBs. Will use T&E but what's the best way to interface to the singles popping out the top of the switch conduit.

 

[breezer]

take them out too, much easier

 

[BJC]

Certainly gives a neater job but not easier than making a connection at the top of each tube. Question is, what is the best way of making a connection?

 

[Belle427]

its just as easy to pull the twin and earth down the conduit with the existing singles that are in there

 

[BJC]

Thanks CH427. Can do that with all but one tube - it serves 4 light circuits i.e. 5 wires plus CPC on top. Could probably get a 3 core and a 2 core down the vertical drop although it might be a bit of a tight fit.

 

[Belle427]

what size is the conduit? are you able to put a jb back on the end with a bush and coupler? not great but cant see another way out

 

[BJC]

The conduit is 20mm. Was going to cut it just after it turned horizontal in the loft, then thread and mate with a JB. I'll take a flyer on getting the cables down and if that fails I'll just rip the tube out the wall and use the channel for the cables.

 

[breezer]

have you got a 2omm die and holder, easier to rip it out

 

[colport27]

Alternatively, you could cut the conduit, ream out the burrs.........and use a knock on coupler.

 

[BJC]

In the past I've used plumbers pipe cutters which leave a really good finish on the pipe and don't damage the cables. Takes a bit longer on steel and doesn't do the cutter any good but the're pretty cheap. So where do I get knock on couplers?

 

[BJC]

Just found out that knock on couplers are not allowed by reg 543-03-06. So rip it out is is. Thanks for all your suggestions.

 

[colport27]

Most half decent electrical wholesalers will have them in stock (or if not in stock be able to get hold of them).
One thing to watch out for though, are you sure its 20mm conduit and not 3/4?............you can still get knock on couplers for both but wouldnt want you cursing me when the one you bought didnt fit........lol.

 

[colport27]

BJC, How come they are not allowed?...........is it because of earth continuity? If so this wont be a problem as an earth wire is going to be installed.

 

[breezer]

you would still have to pulll the cables almost out what ever you did, hece rip it out as i suggested earlier

 

[BJC]

Sorry chaps posts are crossing and it didn't help when my link went down. 543-03-06 is only relevant when the conduit is being used as the CPC, so not applicable to my situation. I've also decided to take up breezers original suggestion and rip this one out.