Armoured Cable

Talk Electrician Forum

Help Support Talk Electrician Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Danby

New member
Joined
Apr 19, 2015
Messages
3
Reaction score
0
Location
Dorset
Hi  there  I have just got planning consent to convert one of my farm outhouse's to a holiday let, the plan is to have separate trades in to carry out the construction, but first of all I need to lay armoured cable in a trench from my farmhouse to the out house , as I have diggers on the farm this is something |I would like to do first ,than when I have the electricians in for their part they can connect up the cable to the house and outhouse,  it is a 50 mtr run  my question is what size cable will I need to get!!!   any help would be much appreciated.

                                                                                                           Danby   

 
stick in a 5 core 400mm² and you should have suitable capacity in that

or try asking your electrician...

or install a suitable duct to pull one through later (and by suitable duct, i dont mean a bit of blue water pipe...

 
Thank you all for your comments I was going to put it in the bottom of a trench 600mm deep  but if I use a duct it will probably be about 63-75 mm ,  to get an electrician involved at the moment as it will not be ready for quoting till probably September.  How do I work out the load required ??

 
just done a quick calc at 3 core xlpe armoured rated 10kw load max 50 amps says 10mm but id put 16mm in to be safe, side. limited to 50amps max from isolator / fuse/

 
just done a quick calc at 3 core xlpe armoured rated 10kw load max 50 amps says 10mm but id put 16mm in to be safe, side. limited to 50amps max from isolator / fuse/
10mm is not suitable IMHO

Anyway - whos says the house is suitable for the additional load? Earthing arrangement? Metering? DNO supply? Load in the conversion?

TOO many questions to be answered before a cable can be decided IMHO.

 
Last edited by a moderator:
Thank you all for your comments I was going to put it in the bottom of a trench 600mm deep  but if I use a duct it will probably be about 63-75 mm ,  to get an electrician involved at the moment as it will not be ready for quoting till probably September.  How do I work out the load required ??

have a read through 7671. its not as easy as your expecting...

or get your sparky in early. long jobs like yours is not unusual

 
Hi There,

There are loads of things to be taken into account before selecting a cable. Your idea of what is suitable, [or even OUR ideas] might well not be suitable, as we are not there on site to have a look.

I know it sounds like we are trying to be awkward, but honestly, this is not the case.. By load, we mean what is going to be connected up to the other end. You might have electric showers, electric cookers, electric heating and a hot tub for all we know.. Your existing supply to the house might not even be big enough to handle the extra load, what you got connected to it already??

As i say, the electrician will have his own ideas of what is needed..

Now, this bit of cable is going to be expensive, £200 or £300... You do not want to be buying the wrong sort!!!!

A 50 meter roll of 63mm twinwall duct [it has twin walls, corrugated to make it flexible, and smooth inside so you can get the cable through] will cost you about £60. Get a roll and install that, and leave the rest to the electrician. Oh, by the way, the PROPER duct comes complete with a length of stuff like fishing line threaded through it. Make sure the stuff you get has this, as you use this to pull a rope through and then you use the rope to pull the cable through!!!

Post as much information as you can, the more info, the more people can help you!!

john...

 
.....and read up on the spec for the hole that will be required..... it will need to be a minimum of 600mm deep with warning tape over,,, I usually put some directly on the duct or cable then again at a depth of 200 - 300mm

also if you're burying cable directly then you will need a decent layer of sifted sand, both below and above the cable

 
My gut feeling is you should be asking your DNO for a quote for a new supply to the the new dwelling, rather than trying to feed it from your existing house.

What about water and drainage? Water really should have it's own supply, or is that going to be a hose from the outside tap?

And what about drainage? Being a farm, it's quite likely to be on a septic tank. Can the existing one handle the extra load? perhaps, perhaps not. Building control will want to know for sure.

Sounds like you are trying to do it on the cheap rather than properly.

 
Last edited by a moderator:
Thanks for all you comments having read what you said  I think my best plan of action as I have overhead cables is to get the power suppliers to run a new feed to the new property,  as there will be dishwashers 2 elect showers and Elect heating it dose have it's own fresh water supply, and lucky enough to be on main sewer,  I can now see it's a bigger job than I thought , and the costs I save in cable will help to pay the power company .

Danby  

 
Hi Danby,

With electric heating your house supply will certainly not cope!! Google the name of the DNO and "new supply" and they will have a form you can download and fill in. Will not be as expensive as you think. You will need an electrician to help you fill in the form though, or post the questions on here and we will help you..

john..

 
Top