Any electricians around?

[lord groan]

I've been on the lookout for some 3 core 6mm SWA cable to run power to my brewshed, I don't have any yet but I was offered something similar recently but hadn't seen this stuff before so I gave it a miss. Googling hasn't enlightened me so can anyone tell me what it was?

It had 3 x stranded copper cores all enclosed in a XLPE? (it was pretty new) sheath, then braided armour on top with an outer layer of clear pvc or similar. The braid wasn't steel, the cable was much lighter and more flexible than normal SWA cable so I assumed the braid was aluminium, it was definitely non-magnetic. Surface of the braid was dull so I'm guessing not stainless.
I declined it cos the armour braid looked a bit feeble compared to steel stuff, but would this have been usable in place of SWA? Does it carry the same current safely?

Thanks

[cqout]

Hello
im an electrician - it sounds like sy cable which is actually a type of flex - the xlpe bit refers to the type of plastic used it is cross linked polythene - it basically means it has a higher operational temperature and is more resistant to damage such as scratching - in my experience electrical wholesalers only tend to stock xlpe versions of cable now. Anyway for our brew sheds when running outside swa or xlpeswa should always be used correctly glanded and the steel armour correctly earthed at each end with no ifs but ls or maybes and dont forget electricity and liquid is highly dangerous and no short cut can be taken - i hope this helps you stay safe

[lord groan]

Cheers cqout,

Thanks for the timely reminder. My plan at the mo is to use the redundant 40A cooker mcb in the house consumer unit as a feed, use 6mm swa to the shed , total length will be roughly 9-10m, I have a new garage consumer unit with a 40A RCD which I will put in the shed and then a couple of mcb's 16A or 20Aish to power the boiler, hlt, lighting and other bits and bobs. I suspect I'll never come anywhere near 40A usage mind you, the highest power item is the boiler with 2200w and 1800w elements so rating it all at 40A is unnecessary in reality but I'm not prepared to mismatch the components, for example I have a very nice length of 3 core 2.5mm swa cable - I bet I never exceed its current rating in practice, but I'm not attaching that to a 40A mcb! It could really get nice and hot before the mcb tripped!
Earthing will definitely be in place.
Thanks for the info btw - googling SY cable came up with what I saw. Nice to know what it was
cheers
lg

[Dave-Leeds]

Where u from LG i have some 2.5mm swa going spare. I wired ny shed and it did the job for me.have about 15m left

Only have a 20amp and 6amp in shed.sockets and lights works great for biab with around 2kw element

cheers

[themadhippy]

I've been on the lookout for some 3 core 6mm SWA cable to run power to my brewshed,

http://www.tlc-direct.co.uk/Products/SW6slash2.html

and the steel armour correctly earthed at each end with no ifs but ls or maybes

even on a tn-c-s supply?

[lord groan]

Cheers Dave-Leeds, I'm in Southampton so a bit far to come to pick it up! I've already got some 2.5mm from a boot-sale but after checking the capacity I decided to use 6mm instead in order to guarantee a 40A capable system. Way over-specced really but it'll leave me tons of headroom to expand or increase the power of the elements in future.
Cheers for the link TMHippy - as a confirmed tightwad who's only just started ignoring my self-imposed limit of £5 for any individual brewing item I'm still hoping to find some 2nd hand or end of reel stuff! But I've been looking for a while so TLC may soon get the business!
I just have to finish gutting and rebuilding the family bathroom before I can get back to brewing.

[sparky Paul]

and the steel armour correctly earthed at each end with no ifs but ls or maybes

even on a tn-c-s supply?

Please don't overlook what hippy said above about earthing - you need to make sure that your earthing arrangements are appropriate for your supply type, and exporting earths is not always appropriate, or indeed safe.

[lord groan]

I've had enough 240v shocks over the years and I don't want any more, especially with 40A available. I'll be using 3 core, both the steel armour wire and the 3rd core will be earthed in the house consumer unit, then I'm intending to bang an earth spike into the ground under the shed and use that too. This may be wrong - I haven't researched that last part yet, but RCD's and earthing will be playing their parts!
cheers

[themadhippy]

How fars shed from house? what id do is run a 6mm 2 core swa BUT only connecting the supply end of the armouring to earth.At the brew shed end put in an earth stake in conect it to the main earthing terminal in the brewshed fuseboard with a lump of 6mm earthing string.As for rcd protection,definatley in the brewshed,30ma and 30ms will do nicley.At the supply end,well thats open to your own interpitation of the regs,if you fit one on you might find it trips before the one in the shed,not fun mid gig, er sorry brew,the cure is to use a higher trip current and/or triping time.However wots the rcd protecting?
O yea and a final tip DONT bang your earth stake through an existing underground cable even if nov 5th is closebye

as a confirmed tightwad who's only just started ignoring my self-imposed limit of £5 for any individual brewing item

But your buying individual meters of the cable ,just lots of em

[lord groan]

Cheers TMH - Corner of brewshed is 1.5m away from the corner of the house but approx 9 or 10m cable required to run tidily from consumer unit into shed via trench or trunking. Would you be happy just using the armour for an earth connection? The thought makes me slightly twitchy, would a 3rd core used as an additional earth create issues, or is it just redundant?

Definitely no cables where the spike would go in, but there is a sewer at an unspecified depth! I'm almost certain about where it is . fingers crossed.

[sparky Paul]

You can export the earth, i.e. connect it to the main earth in the house, or knock in a spike - but under no circumstances do you do both.

If you are using a local spike for the earth, it must be isolated from the main earth. Earth the SWA at the house, but terminate it in a non-conductive box and do not connect the armour through to the external earthing point.

Exporting earths can be suitable in some situations, but not always... and as hippy says, not when connecting to an external building from a tn-c-s supply. If you stick to his plan above, you won't go far wrong. With the potential for exposed metalwork in an external building, my preference would always be for an earth rod.

[themadhippy]

Would you be happy just using the armour for an earth connection

yes and have done many times, but in this case we aint using it for an earth as you dont need one for the link between house and shed,instead the shed earth is coming from the spike.

but terminate it in a non-conductive box

or cut throught the armouring a few foot away from the gland. make 2 cuts about 1/2" apart, wrap a bit of tape around it and cover with a cleat

[cqout]

this is where the regulations are down to interpretation and really electrics such as what you have planned should be done by a qualified electrician who can actually see what is needed in real life not just an explanation on the internet, as all the replies could be deemed as acceptable BUT depends on the situation at hand and the work has to be signed off as this is a domestic situation. Different people have different ideas about how to do things and the next person may do it different again to myself or themadhippy but that does not make it wrong.

Just remember electricity kills and should never be under estimated.