steel shed wiring practice

[Amb]

Well the new shed's finished and now I've got the electrician in to do the wiring. The shed's is all steel with c-section framing. He's only just started (and will be back early next week, fingers crossed) but it looks like the wiring going to the lights and switches, and power points, is just going to lay inside the c section rafters and purlins. I don't know what the regulations are now, but I think I can remember it used to be the practice to attach timber battens to steel framed sheds - the electrical wiring was then fixed to the timber battens. Have the regulations for fixing electrical wiring been relaxed/changed a bit, or am i jumping the gun?

[Barry_White]

The cable is double insulated so it doesn't have to be fixed to timber. The way I did it in my shed was to put it all in conduit and use building wire.

For switches that where fixed to mounting blocks they make plate to go on the back of the mounting blocks.

The sparky should know what he is doing.

Added comments: Maybe the reason that they used to fix timber was so as to be able to nail cable clips to the timber. Today there are special clips made to hold cable to purlin sections etc.

The main concern is that there are no sharp edges that could cut into the cable.

[Tas_Dean]

It's perfectly legit for the cable to lay in the c sections, and held in place by girder clips. As Barry has mentioned, there needs to be some protection around sharp edges.

I'm sure the sparky would put it all in conduit if you asked, but it would certainly cost you a lot more.

[wattlewemake]

Amb when they updated the wiring rules a few years back they made the protection of circuits with safety switches mandatory. This relaxed the cable protection laws quite a bit. Yes it is legal to run cables in c and z section and is usually the quickest and easiest way to do it. The sections provide in most cases mechanical protection from bumping the cables and you just have to remember not to fill the purlins with stuff if there is cables in that one.

Shane.

[cflake]

Amb when they updated the wiring rules a few years back they made the protection of circuits with safety switches mandatory. This relaxed the cable protection laws quite a bit.
Shane.

Are you sure it's mandatory? When the sparky installed a new circuit and power points into the garage, he specifically said he wouldn't put it through the RCD since starting up multiple high current devices tend to trip them very easily (3hp compressor and TIG welder). He issued a CoC. Are you saying it's illegal?

[wattlewemake]

Cflake I would be asking him to explain his reasons and how he is protecting the circuits. If it is a plug in well it needs rcd protection. If he hard wired them well they dont need rcd protection.

Shane.

[cflake]

Cflake I would be asking him to explain his reasons and how he is protecting the circuits. If it is a plug in well it needs rcd protection. If he hard wired them well they dont need rcd protection.

Shane.

Hi Shane,

They are just standard double power points on a 15A (or could be 20A) circuit breaker.

[another termite]

If they are standard outlets then it definatly needs RCD protection to quote the wireing rules
AS/NZS 3000:2000
Clause 2.5.3.1 RCD's with a maximum rated residual current of 30mA shall be installed for the protection of the following final subcircuits in domestic electrical installations
a) Socket outlets
b) Lighting
I would be asking where my RCD was