Cables to run accross concrete floor

[sidekick]

I will have to get tails from meter more than 15m to consumer unit.
Will also gave to either 12m through concrete floor or through a double skin wall to a room with suspended floor for 10m and back 5m through concrete floor. Whats the best way to do and protect this within regs etc.

 

[Engineer54]

So long as there is no reaction element between the materials, i can't see a problem with you using a decent grade of waste pipe as your duct!!

 

[PC Electrics]

SWA does not have to be put in any kind of conduit or ducting. However, you should not lay it directly on top of the hardcore because sharp edges on the stones may pierce the outer shell and allow damp into the armour and cause it to rot out.

As for whether 16mm will be okay - well, we cannot answer that. It will depend partly on the size of the fuse in your switch fuse unit, but primarily on your assessment of the likely peak loading of the installation and your calculations of voltage drop at the end points of utilisation. You wouldn't want to use up 2% of your allowable 3% just in the distribution circuit!!

 

[Engineer54]

SWA does not have to be put in any kind of conduit or ducting. However, you should not lay it directly on top of the hardcore because sharp edges on the stones may pierce the outer shell and allow damp into the armour and cause it to rot out.

As for whether 16mm will be okay - well, we cannot answer that. It will depend partly on the size of the fuse in your switch fuse unit, but primarily on your assessment of the likely peak loading of the installation and your calculations of voltage drop at the end points of utilisation. You wouldn't want to use up 2% of your allowable 3% just in the distribution circuit!!

We know, ....but If you want a re-wireable installation, then it needs to go in a suitably sized duct!!!

 

[sidekick]

Big Thanks to everybody for your advice.
I know how I am going to this job now.
However, can anyone advise where i can get approx 25m of 50mm pvc ducting from. 50m roll too much. Need a run for the swa and then three short runs of about 3m for existing cables from main build via the concrete floor to new consumer unit location.

 

[a12jpm]

Fleabay -


http://www.ebay.co.uk/itm/50mm-Flex...ls_Supplies_Electrical_ET&hash=item5647a7ecf1

 

[a12jpm]

http://www.ebay.co.uk/itm/50mm-Flex...ls_Supplies_Electrical_ET&hash=item5647a7ecf1

Fleabay

 

[Engineer54]

Fleabay -


50mm Flexible Conduit 25m Coil Polypropylene IP44 | eBay

That stuff can be an absolute nightmare to rewire/up-grade at a later date. The walls of the pipe look far too thin as well. And if they are, the weight of the concrete pour will crush the pipe. It won't be re-wirable at all then!! lol!!!

 

[sidekick]

That stuff can be an absolute nightmare to rewire/up-grade at a later date. The walls of the pipe look far too thin as well. And if they are, the weight of the concrete pour will crush the pipe. It won't be re-wirable at all then!! lol!!!

No good for me then. Wsste pipe it is then.

 

[Guitarist]

No good for me then. Wsste pipe it is then.

Or buy flexible ducting pipe designed for laying swa in underground.

 

[sidekick]

Routing of swa, with switch fuse and ducting now all sorted. Many thanks to all who helped me sort this. Not had a lot of experience with swa but all good now.
However, i have now terminated the consumer end of the swa in an adaptable box to three single pole 100a blocks for L, N tails and 16mm EARTH to connect from consumer unit. Difficulty i have is that the adaptable box can be either at floor level then how do i get tails to csu ( not in a cupboard above a freezer )safely and without being unsightly for customers newly built and plastered cavity wall. Or i can sit adaptable box directly under csu to connect tails straight into but then have same problem with swa going up the wall with bulky gland. Any ideas ( run in cavity ?? )

 

[telectrix]

chase trhe SWA in the wall. cleat to brick then replaster.

 

[Guitarist]

chase trhe SWA in the wall. cleat to brick then replaster.

Or channel wall, cleat swa and screw cover over.

 

[sidekick]

With no rcd on this cable does it not need to be 50 or more. Also if chased in would have to chase in adaptable box to line up for gland

 

[Guitarist]

An swa cable does not need further mechanical protection (as it is already protected). The gland can be terminated onto the CU using a banjo fitting and earth tail (if the CU has the facility to be drilled/knockout).

 

[Des 56]

If you are going to sink the swa,then you just as well sink the adaptable box and site the cons unit over it,no joints that way