Advice Needed Re Cable Pulling

[Hefferl]

Hi. I need to pull some cable through 20mm PVC conduit. The configuration is quite convoluted but I'm hoping I've put in sufficient boxes (every 2m or so) and kept bends to a minimum. The max number of cables thru any section is 6 x 1.5mm plus 3 x 2.5mm. According to my CableMate calculations 20mm should suffice.

Previously I've only ever done this in a college workshop bay, on a very small scale.

What I'm asking for is some general advice e.g. should I pull all cables thru together or not?, Should I attempt to pull thru all boxes in one pull or break it down into small runs? whats the best way to apply cable pulling lubricant? that sort of thing.

Thanks in advice for your time.

 

[Andy™]

get some yellow 77

and a draw line

 

[sellers]

draw wire, stagger the cables when tapping onto the draw wire, use yellow 77, or some hand cream, soap etc. apply with a paper towel, use a friend to help feed the cables.

 

[KNB]

Get a friend to feed the cables in as you draw them out. Multiple T&E's (if that's what they are) getting twisted in a conduit will go no where and risk damage to the cable and/or the conduit.

 

[Evans Electric]

Get a friend to feed the cables in as you draw them out. Multiple T&E's (if that's what they are) getting twisted in a conduit will go no where and risk damage to the cable and/or the conduit.

I hope they are not T&Es .  They are not intended to be drawn into conduit ,  nightmare scenario. !!! 

Assuming they are 6491X ,s ...as said above ,  definitely two handed work,  put drums on a spindle , use fish tape .

With quite a few cables its usually better to pull them in all the way , then hook out S/Ws... Neuts etc at the appropriate boxes. 

 

[steptoe]

Get a friend to feed the cables in as you draw them out. Multiple T&E's (if that's what they are) getting twisted in a conduit will go no where and risk damage to the cable and/or the conduit.

if it is T&E he is NEVER going to pull that lot through 20mm.

as above, some slippy stuff [yellow 77] and a friend to feed as you pull, just slap the slippy stuff on with your hands, grabbing the bunch of cables and running you hand down them.

pull all together, staggered starting points,

 

[Andy™]

OP never said anything about T&E...

 

[Evans Electric]

Somebody did .........who was it ....come on ..own up !!!

 

[kerching]

Right chaps [keep this amongst yourselves....right?]....on the topic of staggering cables.

I use a piece of plastic 'chain'....a bit like those reusable cable ties [millities???].

Thread a couple of strands through one 'link'...miss a link ....then a couple of strands through the next link from the opposite side and repeat.   That way all the joins are staggered, one cable is not reliant on the cable it is fastened to, does not rely on insulting tape etc etc etc

If I could be ar$3d I'd go and do a demo setup and post a pic....however I have been outside all day and really cannot be bothered :coat

 

[Hefferl]

Thanks for all the help so far - really useful.

Just to clarify it is 6491x.

Given the attached configuration with basically a high level run around the room, dropping to acessories as necessary how would you pull cable down to and then back up from the DSOs? (2.5mms need to drop to DSO whilst 1.5mms need to continue to lighting)?

 

[Andy™]

measure cable out, cut, then pull both lots through at the same time

 

[Hefferl]

measure cable out, cut, then pull both lots through at the same time

Thanks Andy, but I'm sorry I don't understand.

Do you mean cut the cable allowing enough 2.5s to reach the first DSO and enough 1.5s to reach the light? If so how do I then pull the next set of 2.5s from the first DSO along to the second DSO?

 

[ProDave]

Treat each horizontal leg separately.  Pull all the cables through one leg at a time allowing sufficient for the drop (plus of course the return leg of the ring running straight through).

Then thread the tee over the bundle, obviously threading the drop wires down and the return wires straight through.

then do the next leg etc.

then thread the conduit for the drops on, fit boxes and sockets.

This assumes you wire it as you fix it, which is what I almost always do.

It's all about logic.  Have the cables laid out and long enough to reach to their final destination, then pull them all through each leg together one leg at a time.

 

[NozSpark]

And there was me thinking that conduit systems should be fully assembled before you pull the cables in

 

[batty]

I think you will struggle to get 3 x 2.5 and 6 x 1.5  through one piece of 20mm conduit.

 

[steptoe]

I think the most I have got through was 19 x 1.5mm , and that was a short run with very few bends,

deffo wouldnt meet with current spacing regs though,  :|

 

[batty]

He probably will be OK then.

 

 

[KNB]

I hope they are not T&Es .  They are not intended to be drawn into conduit ,  nightmare scenario. !!! 

I realised after my post that the op did not mean T&E cables but I couldn't be arsed to edit after my last attempt at editing  :Blushing  .

Whilst T&E cables might not be intended for conduit over here ( N.I ) even in domestic installs, we would do switch and socket drops in oval or round conduit so would quite often be feeding multiple T&E's through a conduit.

My advice would still hold true though for 6491x as I would have someone feed them in nice and straight to avoid the cables becoming twisted.

 

[kerching]

With all the bunching being spoken of - I hope the appropriate derating factors have been taken into account  :innocent

C summin or other isnt it ?  ray

   Yep, if I recall sorrectly it is  (  Cramped into as tight a fricking space as possible     X    number of cables X summat else or other)z

where  z     is Splanshnikxs universal constant

 

[Hefferl]

Mission accomplished! Due in no small part to the assistance offered here.

Thanks for all the help and advice provided - it made a real difference.

Learnt a lot about how to and how not to do this, in the process.

Took a lot longer than I thought and made a few mistakes but next time I'll be better. As far as I'm concerned it's all valuable experience!

Thanks again.