Thread: Wiring the Shed

Peace of mind is get a sparky to do it.

I would also get a sub panel if you can afford it. That way as someone else has said you might trip a 16amp breaker on your welder or whatever but the lights keep working. I have 1 circuit for lights, 2 circuits for 10amp powerpoints - 6 doubles on each. I have one additional 15 amp for table saw. All to a lockable sub panel (child proof) with safety switches. I have thrown the 15amp breaker once on the table saw buy never the main panel 30amp breaker.

Whatever you do get RCD on either main panel or sub panel (or both) if you accidentally cut a power cord with a circular saw - you won't get fried ;-)

I ran the 2 cables (2.5 double plus earth, each from a 15 amp c/breaker) to the shed, the sparkie connected a 2 double power points and I ran Arlec power point chains around the shed from them.

No mucking about and all legal.

Ross

It is correct you have to mantain the right gauge for the protection device. It is in the Regs, the only time you can change gauge is to go bigger for part of th circuit that goes through insulation if the whole circuit is not in insulation.

Thanks for all the advice - even the continued and dire warnings .

If I ran the powerpoints in sequence I wouldn't drop the gauge of the wire, I need to move the MIG around the shed and being able to plug it in in multiple locations would be handy.

Therefore, I think your right about the sub-board, would be pretty annoying if something tripped and I was left in the dark, then have to wonder back into the house to flip the breaker - adding power points is something I wouldn't be to fussed about, as I am literally just copying exactly what the Sparky did with the original powerpoint.

But not to sure about slapping in a Sub-Board on my loansome though, unless I can properly test what I have done, which I can't at the moment, I wouldn't want to tackle that.

I will investigate the possibily of a tame sparky who will let me do some of the grunt work and who might let me look over his shoulder whilst he is working because this is not a money saving exercise, I am geniuely interested in learning about this stuff !

Originally Posted by aussie260z

Thanks for all the advice - even the continued and dire warnings .

That's what we are here for ;-) good luck and if you survive let us know how it turned out ;-)

I am not sure what power sockets you intend to connect but if you run 6 mm wire and your only fuse in the circuit is 32A, any one of the installed sockets have to be able to deliver 32A safely. That means that you cannot mix and match as you wish. I am not sure if standard 10A sockets are OK and allowed to be connect to 32A circuits.

What are you welding and what size mig is that needing 32A in single phase?

As Mater Splinter mentioned, you are not allowed to use thiner gauge of wire anywhere in the circuit. Even if you downgrade the breaker, if the circuit starts with 6mm at the breaker end it has to continue with that gauge for the complete circuit.

I'd do as MS suggests, run sub panel in the shed with its own ground and RCDs. Run machinery and light off different circuits so that when you trip the fuse at least you can see.

Wiring the whole shed in 6mm can get very expensive very quickly!

Unless you are prepared to get yourself an ASA3000 to read and understand I'd suggest extreme caution and getting someone who understands electricity to help you.
The best advice given so far in this thread was: "if you have to ask, you should not try to do it yourself".

Electrical wiring is not a sort of thing that you do want to get wrong.

Do you do your own water and gas plumbing as well ?

You can use a thinner gauge in a circuit as long as the circuit breaker is sized to adequately protect the thinner gauge - but it's not common in domestic work.

Judging by the diversity of opinion among 'real' sparkies on this matter (some say you can, some say you can't) I recon the safest alternative for domestic work is not to vary the gauge, otherwise you are relying on the next sparky actually physically inspecting a circuit before increasing breaker size...which is a little too much for me to trust in!

That's what we are here for ;-) good luck and if you survive let us know how it turned out ;-)

Well yes, but it is not like I am planning on buying a bunch of wire, splaying it all over the floor and playing "Lets see what happens if I plug this in here" - Unless I can adequately prepare myself for something like this, I wouldn't attempt it !!!

Originally Posted by Master Splinter

You can use a thinner gauge in a circuit as long as the circuit breaker is sized to adequately protect the thinner gauge - but it's not common in domestic work.

Judging by the diversity of opinion among 'real' sparkies on this matter (some say you can, some say you can't) I recon the safest alternative for domestic work is not to vary the gauge, otherwise you are relying on the next sparky actually physically inspecting a circuit before increasing breaker size...which is a little too much for me to trust in!

Ofcourse you are correct, "The Wiring Rules" are not terribly prescriptive and specifically allow "alternative" arrangements as long as they are no less safe.

So, although as a one time installation, an arrangement where a thinner gauge is used downstream can be made safe by the use of an appropriate fuse, this can hardly be described as a safe practice.

Why don't you get two or three quotes and then decide what to do. It won't cost you anything and you can pick their brains on what's involved.

I had a sub panel fitted. The electrician only took about half an hour so the labor shouldn't cost much. I helped him do it (family friend) and it's not a job I'd tackle by myself, despite being confident with that sort of thing.

I have one double power point just below the sub panel, from there I use extension leads and power boards, all neatly fastened. That's a lot more flexible than a fixed installation if you rearrange your workshop.

Originally Posted by Glennet

Why don't you get two or three quotes and then decide what to do. It won't cost you anything and you can pick their brains on what's involved.
I have one double power point just below the sub panel, from there I use extension leads and power boards, all neatly fastened. That's a lot more flexible than a fixed installation if you rearrange your workshop.

Good advice,
Cheers,
Jim

Originally Posted by Glennet

Why don't you get two or three quotes and then decide what to do. It won't cost you anything and you can pick their brains on what's involved.

I had a sub panel fitted. The electrician only took about half an hour so the labor shouldn't cost much. I helped him do it (family friend) and it's not a job I'd tackle by myself, despite being confident with that sort of thing.

I have one double power point just below the sub panel, from there I use extension leads and power boards, all neatly fastened. That's a lot more flexible than a fixed installation if you rearrange your workshop.

Not only that, when you walk out the door you can flip the switches on the double PP and everything is OFF saving you running around turning individual items off.

Originally Posted by BobL

Not only that, when you walk out the door you can flip the switches on the double PP and everything is OFF saving you running around turning individual items off.

That's what the breaker on the sub panel is for too - one each circuit. Useful for me to disable table saw but leave lights enabled for instance

All done - 4 new Powerpoints installed with little fuss...............well that is not entirely true, 6mm wire is a b£stard and was a real pain to manhandle into position!!!

But, honestly, once I actually managed to get some decent information this was a very straight forward job, including testing the Powerpoints when I was finished to make sure they were putting out the correct amount of volts.

Interestingly, I even managed to use the correct size Conduit where the Sparky did not who installed the original Powerpoint in the shed !!!

Interesting facts that I came across along my travels - besides what has already been mentioned within this thread.

• If you install 6mm wire within Conduit, it must be 32mm, run 2 x 6mm wires and that conduit size has to increase to 50mm (This information was contained in the Australian/NZ Standards Link posted within this thread)
• All connections in the wire have to be inside a Juntion Box.
• DONT USE those twisty style connectors, use BP Connectors.
• No matter what anyone tells you, 3 x 6mm wire does not fit inside a normal BP Connector, need a BP Connector with an outlet on either end !

This stuff was not like Automotive wiring - really difficult to manhandle into position, but eventually got used to it. I Contained everything in conduit, which was probably overkill because the Cable is inside a shed, but because there is no inner wall I thought it would be best.

I purchased all of my gear from either Bunnings or Project Lighting, both sell Clipsal and I found anything that Bunnings sold was usually a lot cheaper than what Project Lighting sold, except for the 6mm Cable - Got that for $3/M at Project Lighting whereas Bunnings was after almost $6/M!

That's what we are here for ;-) good luck and if you survive let us know how it turned out ;-)

Honestly - everything is colour coded, Black-Red-Green/Yellow - You are just literally plugging COLOURED wires into COLOURED sockets, how anyone can make a mess of that is beyond me - sure not actually having a read of the Regs, getting decent outside help and then going down to your local Electrical wholesaler and looking at the products you will be using to get a feel of how it goes together, issues will certainly come about!!!

But, compared to some of the stuff I have done on the car, like figuring out a change-over relay to power a thermo fan, or installing a later model steering column and Combination switch (in order to get Intermediate wipers) but still using the old Wiper motor, was much, MUCH more difficult than installing this wiring into the shed.

Besides constantly checking that the Mains Power was still off (Some of the advice on this forum certainly put the fear of god into me ). I really didn't have to use my brain much at all during this entire process, the difficult part of this whole excersize was manhandling the 6mm wire into the Junction Boxes - that was tedious!!!

Be good to eventually install a Sub-Panel because now I have to remember to turn off all the Powerpoints, but when I learn a bit more I will tackle that job !!!