Armoured cable needed under garden?

[wanabechippie]

Hey.

Thinking of moving my small wood-workshop to the top of my garden. There is an existing power supply that was connected 5mths ago when the house was re-wired. The cable for it just crosses the 2m gap between the shed and the house, suspended by the earth cable around 3m above ground.

Was wondering; what sort of work is involved in running the cable some 25m across the garden to the proposed new site? Buried amoured cable or wire-in-conduit?

Wont be doing the work myself as I know less than bugger all about electrics. Just want an idea of the work involved.

Cheers

 

[Adam_151]

Armoured is the easiest way

Singles in galv conduit would be another way, but not as easy, etc

 

[Chri5]

25 extra metre's might require you to down size the capacity of the existing shed service.

That depends on the design and use of the existing set up.

Would I be right in thinking you have an existing SWA / armoured cable feeding the shed at the moment, do you know what size cable it is and what size fuse supports it?

It would be wise to consider that the existing sized cable may been fine running 20A at it's current location, but + 25m distance could reduce the current capacity due to voltage drop.

An example would be that 4mm SWA would support 20A a radial cct that's 10m from the main supply, but would be pushed at 35m so the way forward would be to joint the SWA to a new length install it and drop the fuse down to 16A.

My OSG is in the car, so don't take my figures as fact. Post the cable size and an idea of what it runs in the shed, give some idea of distance of the existing cable run (fuse board to shed) and tread your new cable route (dig might be diverse, not line of sight), confirm the distance and either I or someone else will offer further advice.

 

[breezer]

Would I be right in thinking you have an existing SWA / armoured cable feeding the shed at the moment, do you know what size cable it is and what size fuse supports it?

know less than b*****r all about electrics.

wanabechippie, you may (or not) want to offer to dig the trench

 

[wanabechippie]

Chri5: Thanks for your input, but you said a whole bunch of things I do not understand I really do know buggery-diddly-squit about the leccy!

As breezer said; I'd probably be able to handle the digging-of-the-trench bit with out killing myself!!

Not really sure what size cable is used at present (would it help if I said it's grey and looks like the cable used in the ring main? ). The shed is used for woodwork. I run a flourecent light all the time I'm in there as well as a chopsaw, router, aircompressor etc as and when i need them but never at the same time.

I was just after an idea of what the job would entail as regards cable used and how it would be passed across the garden as well as what I could do to try and keep costs down.

Cheers.

 

[davy_owen_88]

For a woodworking shop you really want to keep voltage drop to a minimum and you also want to make sure you have plenty of spare capacity for future upgrades (16A supplies etc.) Consider the lights, radio, your largest machine and the dust extractor running... you won't be able to hear the radio but that's beside the point The total demand will most likely be close to 25A

If your budget will allow consider running 10mm² cable, but definitely not less than 6mm² - any less and you might get problems with motors not starting due to their high startup currents causing excessive voltage drop.

You can run the cable overhead or underground. If you run it underground you will need to dig a 60cm deep trench, if overhead you need to consider any trees etc that might be in the way.

 

[ricicle]

If you run it underground you will need to dig a 60cm deep trench

45cm (Don't knacker the poor guy out Davy)