3 core cable in flexible conduit?

[Rtony]

Hello all,

I've removed the old plaster (most of it fell off) from the walls in the back room of my old stone house. Now I need to run some cables around the walls, preferably in between the stone, for a light and some power sockets.

The question is: Do I need to run the 3 core cables through flexible conduit?

Thanks,

Tony

 

[PaulT]

No, you need to run three separate single cables through the conduit. It can be made easier by using a 'fish' wire. A flexible plastic cable with at one end a metal part with an elongated hole that use use to secure the cables to - you run all three at the same time.

[Rtony]

Thanks for replying PaulT.

There'll be a lot of digging out to do then.

A couple more queries:

Is it better to thread it through the conduit first then fix the conduit in the wall?

I have a reel of conduit, what's the metal wire that runs the length of it for?

Regards

[Kong]

The metal wire is for pulling through the cables (wire) you wish to run in the conduit. The plastic fish wire Pault refers too is for pulling through cable (wire) when you have lost or don't have the original pull through wire.

[PaulT]

You also use the fish wire to replace / add to cables in existing installed conduit.

Pull the cables in before installing the conduit - in fact you can buy conduit with the cables already installed BUT I have always found it is more expensive than buying empty conduit and the cables separately.

Do use the correct size conduit to suit the correct cables for what you are doing.

[Lehaut]

I think you could only use the fish wire if you left it in the conduit! To do this, you need to pull through your 3 wires plus a piece of string. Once you have the wires/string through, you can attach the fish wire and pull it back through leaving you the 3 cables and the wire in the conduit. Its not easy to pull 3 x 2.5mm cables through say 8 meters of gain (we usually do it in a straight line, me at one end pulling, wife at other end with gain and cables. Pushing a thin wire back through with the cables in place would be imo, almost impossible.

[Chancer]

I think technically at least that may be frowned apon if discovered during a Consuel inspection as you would have an uninsulated (potential) conductor within the gaine.

I assume that you do it if you might wish to add a conductor at a later date but it would be very hard with the other cables in position (been there!) and you could erode through their insulation (been there as well!), better to pull out all the wires pulling a fish wire behind them then start again with the new conductor.

As an aside when pre-filling a gaine dont try to pull the wires through it, attach them to a fixed point and pull the gaine over them.

[BIG MAC]

Hi Chancer can you elaborate? I am trying to visualise what you mean about drawing the gaine over the cable.

[Chancer]

Bad description as ever.

Tie one end of the draw wire to a fixed point, pull the gaine out straight (not easy) tie the wires to the other end and then roll them out straight away from it to the same length as the gaine, easy with reels hard with couronnes.

Then pull the gaine back over the wires against the tension of the draw wire.

I have monopolised 200m of the footpath most of one summers afternoon doing this to save not much money at the end of the day, all good for my reputation of the mad Anglais though.

[Lehaut]

I have found that when we have used the pre cabled rolls, when you cut it, the cables tend to disappear and we end up cutting off another 15 cms of gain to find them. Similarly, the gain with the fish wire, you need to make sure, if doing short lengths, you attach the fish wire to the outside (hook it over) otherwise it tends to disappear inside too. Presume its something to do with the spring in the wire maintaining maximum circumference. In doing 100 meters, you must have really attached the wires to the fish wire (have also seen thin nylon). Cannot imagine the language if it comes off half way through!!

[Théière]

Oh bother, I said.  just sucked through the fish line with a scrunched up paper ball attached to the end and a vacuum cleaner. 

[BIG MAC]

Cheers Chancer I should have seen that coming for some reason my brain just wasn't getting it, I now see three reels on a steel bar suspended on an axle stand each end the draw cord already in the gaine and affixed to a set point then connected to the three cores drawing the gaine back over the draw cord then moving the axle stands back to spool out cores and slide the gaine over...not sure if I explained it any better but at least I have the image now, ta

[Chancer]

We both are far better at observing things than explaining them, I think I get what you say and yes I think thats it, twas the drawing the gaine over the draw cord i thought was wrong but yes as you pull the gaine back the draw cord is pulled out at the fixed end and the wires go in at the other end.

I remember doing mine now, it was actually winter and there was snow on the ground, I rolled out 100m of cable to the right of my property then 100m of gaine to the left and tied off the draw wire to a fence post, after sorting out the other end I pulled and realised that it had detached from the fence post, walked back to see footprints in the snow of the garden (I was on the footpath behind the rear gardens of the houses) to and from the fence post, the drunken teenage son was mouthing obscenities at me from the salon.

[BIG MAC]

I am not sure I would have thought of doing it your way straight away but I would probably have got there in the end. Teenage sons..yeah....I had a couple of those...much use as a handbrake on a canoe...nice lads but handless lol