Pulling in swa

[rainstorm]

Good evening all
Got a 200m run of 3 core 10mm swa to install in a trench. Rather than pulling it through a duct, was wondering if anyone has ever pulled the duct over the cable, then dropped in into trench.
Duct is 50mm internal diameter flexible type. Might be a non starter, just weighing up options.
Thanks for any help.

 

[cliffed]

No need for ducting if laid in properly obviously if required by the client then add another duct.

 

[Pete999]

Good evening all
Got a 200m run of 3 core 10mm swa to install in a trench. Rather than pulling it through a duct, was wondering if anyone has ever pulled the duct over the cable, then dropped in into trench.
Duct is 50mm internal diameter flexible type. Might be a non starter, just weighing up options.
Thanks for any help.

50mm = 2 inches 10mm SWA 3 Core gonna be tight hope you have a strong pull cord good luck, same as what cliffed said, in complete agreement with him

 

[rainstorm]

Thanks.
Was wanting duct is to protect against stones etc.
Any thoughts on the chances of pulling the duct over the cable?
Comes in 50m lengths.

 

[Yozza19]

4 inch is the minimum I would be using and a few draw pits for 200m

 

[snowhead]

I'd say non starter, unless you did it with several men / women / others, to lift the weight.
50 mtrs of SWA weighs around 40kg so when you're dragging the 50mtr length of duct you've got 40kg of SWA bearing down on it once you get a full length of duct on the cable.

At best you'll rip the duct, defeating the whole purpose of using it.

 

[MJPD29]

That's a very expensive cable for about 13ish amps

 

[MJPD29]

But on another note I either wouldn't install a duct unless requested my client or 4 inch duct. Wouldn't bother with 50mm it'll be a nightmare

 

[pc1966]

If you already have bought the duct and it is not reusable/returnable then you might as well put it over the SWA before dropping it in. But 200m is a long pull no matter what, though a team of heavies and plenty of cable lube might allow it but really you ought to be looking at something bigger.

If you do decide just to put the cable in the ground directly then make sure you have 5-10cm of sand down first, and the same on top afterwards, to stop stones and other stuff from damaging it as you back-fill.

 

[rainstorm]

Thanks.
Think sand and no duct is sounding best.
It is an expensive cable Matthew, but necessary.

 

[IAmSparkytus!]

Just being nebby but what's it feeding?

 

[Dustydazzler]

Sand , lay cable . More sand , warning tape, back fill trench

job done

forget the ducting , waste of money and time

 

[DefyG]

It is an expensive cable

And the sand wont be cheap! 200m at 200mm thick (100mm below cable and 100mm over the top) and say 200mm wide trench = 8cu m (8 builder bags worth)!

 

[telectrix]

save all the hard work. hire Mighty Mole for a day.

 

[MJPD29]

Just being nebby but what's it feeding?

Single socket maybe?

 

[pc1966]

Single socket maybe?

Well 5% drop and 10mm single phase comes to 12.3A over 200m so not far off it!

 

[DefyG]

Single socket maybe?

Doubt it could be that, I just did a quick VD calc and 5% is exceeded at a load of 13A over that distance for 10sqmm

 

[DefyG]

I calculated 7.54v at 13A over 200m but at 12.3A it could be slightly under 5%

Well 5% drop and 10mm single phase comes to 12.3A over 200m so not far off it!

but either way certainly nowhere near 3% for lighting!

 

[pc1966]

I calculated 7.54v at 13A over 200m but at 12.3A it could be slightly under 5%


but either way certainly nowhere near 3% for lighting!

~12A is a lot of LED illumination!

Football park?

 

[Mike Johnson]

If pulling a 200m length of duct over a 200m length of SWA with a 200m pull cord you need 400m of space in a straight line to do it, and that is only if the draw cord is already in the duct, I did this with an alarm cable, but only 100m, would be easier in 50m sections with draw pits.