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Posted By Topic: Connecting a rangehood

Johan
Sep 04 2012 19:20

Hi,

Over the weekend I've installed a rangehood in our kitchen, it did not have one before. It came with a power plug moulded on so for now it's just connected to a socket close to it, still waiting to be properly wired in.

What would be the best/easiest way to do it, with the interest to get an easy sign off.

1: Add a new socket, extending it from an existing one less than a meter away and hide it behind the rangehood's cover.

2: Permanently wire it into an existing socket, and replace the socket with a 3-switch type (so the 2 switches for the 2 socket, and one switch for the rangehood). (Is a switch mandatory?)

3: Both 1 and 2.

I'd prefer number 2, less materials and less work. Not that it makes a lot of difference. Also, I'm not "adding" another socket, so can I get away with not having to get a sign off? (probably wishful thinking, I know).

Cheers
Johan.
   

AlecK
Sep 05 2012 09:26

you're adding a point to a circu9it, so a COC is required regardless which method you choose.

If you add a socket, it has to have RCD protection. Since cable costs will be the same, and you buy a socket either way, this is the only real difference in materials cost (assuming existing circuit doesn't already have an RCD).


   

Johan
Sep 05 2012 13:00

Ok, good point about the RCD, did not think about that one yet. Will wire it in then and get a new 2 way socket with extra switch.

From what I can read, I'm allowed to replace the socket, and wire in the rangehood but not actually connecting it to the existing wiring.

Cheers
J
   

AlecK
Sep 05 2012 16:27

sounds like you're not a licensed electrical worker?
In which case you're correct about not connecting - not allowed to even "enter" the existing socket; and you'll need to find an Inspector to check, connect, and certify your work.
   

I
Sep 05 2012 17:23

don't think thats quite correct AlecK , reg 64 ( 2 ) (c) allows him to remove and replace a socket outlet , hes just not allowed to connect the new bit till its been inspected .
   

AlecK
Sep 05 2012 18:05

True enough.
I was referring to ESR 64(2)(b)(i), which forbids entry to any enclosure where live conductors are likely to be present.
Remembering that the N is a live conductor.

Presumably ES consider that removing / replacing doesn't require "entering" the enclosure.
It must be done as per ECP 51; and strangely there's SFA in that document telling them how(only bit I can find says to pull fuse / turn off mcb). Which will make it difficult to do the work "in accordance with" the ECP.

Yet there is advice on how to do work on switchboards, meter boxes, and main earthing systems - which homeowners are not allowed to do, and never have been. The thing is a mess, written seemingly without any regard to the limits of work for homeowners, and getting seriously out of kilter with the "parent" Standard (AS/NZS 3000).

Bottom line is that the homeowner must not bring the cable for the extension of the circuit into the flush box / mounting block / wall cavity which encloses the existing socket terminations.
   

Johan
Sep 06 2012 08:33

Interesting, I'm not allowed to bring a wire into an enclosure which holds live cables (which seems reasonable in a way), but at the same time I'm allowed to replace an existing socket, which seems much more risky as I'll be actually disconnecting/connecting wires. And what about the roof space? Cables are running there in the open, can that be called an "enclosure" as well then?

I've just thought of another option though. The rangehood is located at a spot where a light fitting was alrady fitted. So I removed that. It's a light that was on an individual switch, not switching other lights, so that switch just has become redundant. Can I simply use that wire to connect the rangehood too. It's got earth too. I don't even need to relocated any wires, simply connect it up.

It does mean obviously that the rangehood will be on the same fuse as the lights, not sure that is a problem.

And nope, I'm not a registered electrician, "just" a homeowner with a background in it.

Cheers
Johan
   

TEX
Sep 06 2012 08:58

Johan even though you are allowed to do "limited" electrical work as a home owner, under the ECP51 all work still requires to be inspected by a licenced electrical worker.
Don't get me wrong, when I say that i guarantee that a large percentage of home handy man jobs dont get certified just for the simple fact that the home owner is a "cheap ass". I say that not from a perspective of protecting the electrical industry trade, but in the fact that many works are done without any knowledge of why and how the wiring standards work. Yes a wire is a wire, but can it supply enough current for your appliance needs? When it doesnt and your house burns down, what will the insurance company say??

Let consider your situation. If you use the old light fitting, then:

1)Need to consider if the wiring that is supplying that old light fitting has enough current carrying capacity. It would need to be a 1.5mm TPS atleast without taking any run lengths into account since you are running a 10A appliance.

2)The circuit as a whole would need to be protected to suit the wiring, which it should be since it is a lighting circuit.

3)Since you are adding a power point even to an existing sub circuit, it requires you to have it RCD protected, even though it is a lighting circuit.

It is good that you are asking the right questions. The decision to do it yourself or get someone licenced to do it, is in your hands, not because the EWRB will ping your butt for doing illegal electrical work, but in the fact if you do it wrong and you house burns down, you get electrocuted, someone else gets electrocuted, you will be liable.

TEX


   

The Don
Sep 06 2012 09:22

Tex : I don't think he is talking about putting a plug socket on the lighting cable , but simply hooking the range hood to it .
Since a range hood is nowhere near ten amps then it can go on the lighting circuit no problem, and since a home owner is allowed to connect and disconect fixed wired appliances the he is legally allowed to go ahead and do what he has suggested and further more he would not even need to get it checked or inspected .


   

AlecK
Sep 06 2012 10:00

yes; as long as the fitting (rangehood is appropriate for the circuit) this would be simply replacing a light fitting with a rangehood (a light and a fan).
And as TheDon says, the rangehood is almost certainly appropriate in terms of load, and the subcircuit has an earth wire at that point(not always the same as having an earth, but testing will prove whether it's connected back to swbd).

Both the removal and the connection are covered under ESR 64.
No RCD required
No certification or inspection required

Testing is required, in accordance with ECP 51.

Johan: if you haven't already, download ECP 51 from the Energy Safety website.

The existing light switch will be OK as a control switch and the circuit breaker at the switchboard will provide the req'd means of isolation.
But DON"T use the light switch to make the wires "dead" while you work on them, turn off the circuit breaker (or pull fuse) at switchboard.

After you've connected, measure the continuity of the earth, from the body of the appliance, to some other earthed metal (since you're not allowed into the switchboard to measure to the earth busbar), and anything under 1 ohm will be OK. The range / hob should have some earthed metal you can get at easily.
   

TEX
Sep 06 2012 10:18

Johan even though you are allowed to do "limited" electrical work as a home owner, under the ECP51 all work still requires to be inspected by a licenced electrical worker.
Don't get me wrong, when I say that i guarantee that a large percentage of home handy man jobs dont get certified just for the simple fact that the home owner is a "cheap ass". I say that not from a perspective of protecting the electrical industry trade, but in the fact that many works are done without any knowledge of why and how the wiring standards work. Yes a wire is a wire, but can it supply enough current for your appliance needs? When it doesnt and your house burns down, what will the insurance company say??

Let consider your situation. If you use the old light fitting, then:

1)Need to consider if the wiring that is supplying that old light fitting has enough current carrying capacity. It would need to be a 1.5mm TPS atleast without taking any run lengths into account since you are running a 10A appliance.

2)The circuit as a whole would need to be protected to suit the wiring, which it should be since it is a lighting circuit.

3)Since you are adding a power point even to an existing sub circuit, it requires you to have it RCD protected, even though it is a lighting circuit.

It is good that you are asking the right questions. The decision to do it yourself or get someone licenced to do it, is in your hands, not because the EWRB will ping your butt for doing illegal electrical work, but in the fact if you do it wrong and you house burns down, you get electrocuted, someone else gets electrocuted, you will be liable.

TEX


   

TEX
Sep 06 2012 10:26

GAAHH!! Aways get caught out with the bug in the forum with it repost if you refresh the page!!

AL and Don you are bang on if he is to directly attach it to the existing light fitting (hardwired), since I would classify a rangehood as a recessed luminear myself. I guess it is down to how you "work around" it.
Reading the other thread about a subby connecting a rangehood to a PP which is hidden from view, so not normally accessiable, its similar but different rules apply.

I think it is great there are people on here who are happy to expand their knowledge and even better others who are willing to share their knowledge without thinking they will loose work because of it.
   

Johan
Sep 07 2012 17:11

Hi Guys,

Thanks for all the feedback, and good to know I can connect it up to the old light wiring. I'll double check the power rating and wire gauges etc.

My primary reason to asking here is to make sure I do it right. I'm quite happy to pay for an inspector if needed so, having said that, I'd like to avoid unnecessary costs too as any homeowner does.

The pointer to ECP51 was quite helpfull. I'm from the Netherlands originally and have done quite some electrical work there. I'm confident I can do things in a professional manner, it's just sometimes hard to figure out what is allowed and what not, and how it's done here.

Thanks again for the input,

Cheers
Johan