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When it comes to doing your own electrical work. . .
Are
Aussies
DUMBER
than
Kiwis?
By Ross Tester
Did you know that it if you want to paint a wall and need to
unscrew a power outlet or light switch, you cannot do it
legally in any Australian state? Nor can you replace a light
switch or power outlet, install a dimmer or ceiling fan. Nor
anything else which involves any form of electrical installation,
repair or modification. But you can in New Zealand!
I
n fact, in NSW (and probably other states), at the very
moment there are radio commercials saying how dangerous it is to attempt your own electrical repairs. It
was these commercials which in part prompted this feature.
The same commercials, incidentally, state that one in five
“handymen” do exactly that. Naughty, naughty.
Like all other states, Queensland law says that you have
to call a licenced electrical contractor to do any electrical
12 Silicon Chip
work involving fixed wiring. Unlike most other states, in
Queensland you cannot even repair plug-in appliances
(such as jug elements, etc). But we are getting ahead of
ourselves.
Now let’s suppose that a handyman, unlicensed, does
some electrical work. It may be absolutely exemplary but
by definition (and law!) such work is declared “dangerous”
and cannot even be tested and certified after the event by
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Non-contact mains voltage detectors:
an essential item in every toolbox!
an electrical contractor! There have been prosecutions, for
example in the Northern Territory where a contractor did
certify work done by an unlicensed person. The contractor
was fined and lost his own licence.
It doesn’t matter that work may have been done to a
higher standard than the electrical contractor would have
done it. At the risk of earning the wrath of every sparkie
in the land, they are normally working at the maximum
speed to the minimum acceptable standards, simply so
they can earn a buck.
But even the very best quality unlicenced work can
never be “legal”.
Now, if you were across the pond in New Zealand, such
actions are quite legal. In fact, in New Zealand you can not
only change a power outlet or light fitting, you can add additional power outlets, even rewire your entire home if you
want to right back to (but not including) the switchboard.
The NZ power authorities actually publish information to
help the do-it-yourselfer do it him (or her) self.
If you don’t believe us, have a look at www.consum-
eraffairs.govt.nz/mediacentre/wordofadvice/2004/
ECP5051.html or www.energysafety.govt.nz/templates/
Page____17682.aspx
They’re just a couple from a number of sites setting out
what is completely legal. But the Kiwis go even further
than that – they actually publish instructions to show
home owners how to do it – safely! Again, have a look at
www.energysafety.govt.nz/upload/33458/ecp51v18.pdf
and www.energysafety.govt.nz/upload/33456/ECP50v18.
pdf
Why the difference?
Maybe the Kiwis have different equipment to that in
siliconchip.com.au
Unlike neon test screwdrivers, non-contact tester
s, as their
name implies, do not require any contact with live
circuits.
This is very important for safety – it’s easy to see
if the circuit
is dangerous simply by bringing the tester tip
close to it (ie,
within a centimetre or so). If you are doing any sort
of electrical
work, one of these devices is absolutely essential.
They’re rated
to detect AC voltages from 110 to 1000V.
Two models are shown above: at top is a Digite
ch QP-2271
“Voltfinder” from Jaycar Electronics. It not only glows
bright red
when it senses a live circuit but also has a relatively
loud beeper
to warn you. In addition, there is a handy bright LED
torch built in.
It retails for $17.95 at all Jaycar Electronics stores
and webstore.
The lower model is a Fluke VoltAlert 1AC-II. It is small
er than
the Digitech and also appears to be slightly more sensi
tive. It too
features a warning beeper but no torch and retails for
$48.00 from
electrical wholesalers and some hardware stores
.
Both of these will easily identify a live power outlet
from the
front (ie, while it’s still in the wall); they’ll also detec
t live wiring
from outside its plastic outer sheath. In fact, they’l
l also yell their
heads off if they’re next to your mobile phone when
it rings!
Australia, perhaps easier to use and understand? No, it’s
absolutely identical. Same voltage, same fittings, same
hardware. . . same! Do the Kiwis operate to a different set
of electrical standards? No, in fact the standard is called
AS/NZS:3000 – that’s Australian Standard/New Zealand
Standard number 3000. (It used to be called SAA Wiring
Rules).
Why then are the regulations in the two countries so
different?
June 2008 13
Are Aussies that much dumber than Kiwis?
Absolutely, if we are talking about the bureaucrats and
politicians. And quite possibly the general public as well,
because we have allowed the bureaucrats and politicians
to force their demonstrably false regulation on us.
What the Kiwis obviously have is a much more enlightened, sensible and informed Government and bureaucracy
(well, certainly in this regard!).
It’s all about safety
No it’s not. That’s the line that Australian electricity
authorities trot out whenever the subject is raised – and
they are supported by electrical unions, by electrical contractors, etc, who want to ensure that they keep the work
to themselves. And they are supported by mainstream
media and tabloid TV shows who are convinced (conned?)
that having handymen doing their own wiring will cause
corns and callouses, rot wooden legs and bring plague and
pestilence to the land.
We mentioned New Zealand a moment ago. Compare
the statistics between Australia and New Zealand: they
ably demonstrate that electrocutions are at least as rare in
New Zealand as they are in Australia. Table 1 shows the
comparison between the Australian states and NZ for the
years 2005-2006 (the last year currently available).
Notice something?
With the exception of the Northern Territory (whose
figures are skewed by the low population), most Australian states and New Zealand have pretty similar electrical
14 Silicon Chip
STATE
NSW
VIC
QLD
WA
SA
TAS
ACT
NT
Population
(millions)#
6.8
5.1
4.1
2.0
1.6
.49
.34
.2
NZ
4.1
# Australian Bureau of Statistics, 2006
Electrical
Fatalities*
6
6
3
3
0
0
0
3
Fatalities per
Million Population
0.88
1.17
0.8
1.5
15
3
0.7
* Electrical Incident Data 2005-2006, ERAC
Table 1: wouldn’t you expect New Zealand to have
significantly higher electrical fatalities than all Australian
states, if doing your own electrical work is so dangerous?
It is clearly not so!
fatality figures (note that we are not breaking these down
into types nor locations, though if you are interested, those
breakdowns can be found on the Electrical Regulatory
Authorities Council website: www.erac.gov.au).
And there is certainly no suggestion that these fatalities occurred due to unlicensed people doing their own
electrical work.
It would appear from our reading that the majority are
either workers in the electrical industry (complacency,
perhaps?) or, far too often, accidents such as allowing crane
siliconchip.com.au
jibs or boat masts to contact high-voltage overhead lines.
Leaving the Northern Territory and the three states
which had no fatalities at all in the 2005-6 year out of the
equation, Australian states experienced between 0.8 and
1.6 deaths per million people.
But the one thing that stands out, more than anything else,
is New Zealand, with little in the way of restrictions, has
less fatalities than any Australian states which had them.
Now if the Australian authorities are correct – that it is
dangerous to do your own electrical work – wouldn’t you
expect that to show up in the stats? Wouldn’t you expect
New Zealand to have significantly higher fatalities, because
doing your own electrical work is so dangerous?
As the song says, “it ain’t necessarily so”!
Let’s look at another set of statistics – the United Nations Fire Statistics Study (www.genevaassociation.
org/FIRE%20N%C2%B0%2014%20-%20September%20
1998%20.pdf)
Certainly, these statistics are for more than house fires.
And no-one is saying that all fires are electrical in origin
(although just about every time you hear about a house fire
on the news, an “electrical fault” is blamed).
If it was so dangerous to do your own electrical work
it’s not too long a bow to stretch to assume that more fires
would be caused by that electrical work being done by
unlicenced people.
Woops. New Zealand has a lower cost of fires per population than Australia. Scratch that theory! Again we have to
ask, are Aussies that much dumber than Kiwis?
In this regard, the authorities seem to answer YES!
siliconchip.com.au
What is the Australian Supply Voltage?
Ask most Australians what the supply voltage is and
(if they
know!) they’ll say 240. Indeed, most electrical equip
ment made
in Australia is labelled 240V, 50Hz.
But they’d be wrong! That’s what it used to be . .
.
In 1983, the International Electrotechnical Comm
ission initiated a program to standardise the 50Hz internationa
l voltage
at 230/400V.
On 23rd February 2000, a new Australian Standard,
AS600382000 came into force which replaced the original
standard. In
a nutshell, it stated that in normal circumstances,
the nominal
supply voltage should be 230/400V, +10%, -6%.
Another Australian standard, AS/NZS3000, states
that the
voltage drop (caused by load) at the customer’s prem
ises should
not vary by more than 5%. Therefore, the supply
voltage must
be 230/400V +10, -11%, or between 205-253V/3
56-440V.
Supply authorities recognise that a lot of electrical
equipment
would struggle with the lower figure so endeavour
to keep the
single phase supply at 230V, +10, -2% (225-253V
).
Perhaps not quite coincidentally, this range confo
rms to the
previous 240V standard!
Reproduced below is the New Zealand government’s “Guide
to Doing your own Electrical Work safely and legally” –
what you can and cannot do. This enlightened approach has
not resulted in more electrical accident fatalities, pro-rata,
over the Tasman. The guide is a little small here to read the
fine print – but you can download a copy yourself on www.
energysafety.govt.nz/upload/31994/brochure.pdf
June 2008 15
In this regard, the authorities seem to answer YES!
Not only are New Zealanders allowed to do their own
electrical work, the NZ government publishes a number of
guides to tell them exactly how to do it, with safety paramount. They are savvy enough to realise that people ARE
going to attempt their own electrical repairs and installations, so go out of their way to make sure that those people
are given the information they need to do those repairs and
installations responsibly and, most importantly, safely.
No amount of radio advertising is going to stop people
in Australia doing the same thing. It’s simply a fact of life.
And prosecutions for doing so are so rare that we couldn’t
find very much data at all. There were related prosecutions – and we’re sure there would be some prosecutions
out there. But not that we could track down.
A little knowledge is a dangerous thing . . .
So the proverb goes. But no knowledge is much worse.
The following example is not exactly doing your own
“electrical work” but it’s close enough – and it serves to
illustrate the point.
I once had a next-door neighbour who owned an electric Flymo. One day, the inevitable happened and she ran
over the power lead, cutting it. So she went down to the
local hardware store and bought a 240V cord-top plug and
socket. So far, so good.
There were pretty pictures on the back of the packs showing which wires connected to which pins, how long to cut
and strip each wire, etc, which she managed to achieve
without drama. The only problem was that she fitted the
female socket to the lead attached to the mower and the
male plug to the lead from the power outlet – that is, male
at both ends of the power lead – so that when it was plugged
in she had live, exposed pins ready to do their worst.
I was aghast – but at first she couldn’t understand the
problem. It took a while, then she said “why didn’t they
explain that to me?”
The reason, quite simply, is that authorities here are not
explaining anything – for safety reasons, of course.
But withholding the information is not going to stop
people, like my next door neighbour (who by her own
admission knew nothing!) – they’re going to do it anyway
and make the mistakes that kill people.
This is one of the “modern” style outlets (switches are the
same) with a removable face plate so that (theoretically!) it
doesn’t get painted. However, it has been painted over – but
even more importantly, it has a faulty switch mechanism
(left side) so the whole outlet will need to be replaced.
16 Silicon Chip
Closer to home, (literally!) when I moved into my home
many years ago, there was a bare 240V globe in a socket
hanging off a branch in a tree near the entrance. A length
of perished figure-8 cable ran back through various tree
branches until it disappeared through a ventilation grate
under the house. I asked the previous owners about it and
they told me that it was there when they bought the house
but it had never worked.
Talk about Jerry-built! I decided to remove this forthwith
– only to find the circuit was live (the globe was blown!);
it was wired in parallel to the oyster light at the front door.
So it was live whenever the front door light was on!
Of course the authorities would point to this example and
say “See, we told you so. People should not be allowed to
do their own wiring.” We say that if whoever (Jerry!) had
put this flawed light circuit in had the correct information
given them, they would have put in a proper light circuit
using the correct cable, conduit, switching and so on.
It’s precisely because they didn’t know how to do it
properly that they did it incorrectly – and fraught with
danger.
In New Zealand, this information is supplied by the
government in order to prevent those very mistakes.
They make the rather strange assumption that it’s better
to have live people with appropriate knowledge than dead
people with none.
Repairing appliances
Again in New Zealand, D-I-Yers are allowed to repair their
own electrical appliances, such as jugs, heaters, toasters,
etc – especially those with such things as elements and the
like which can and do fail.
Already in some states of Australia, such is forbidden
by law, despite the fact that you can buy replacement jug
and heater elements (and other parts) over the counter.
From the mumblings we’ve heard, it probably won’t be
too long before all states follow suit. Could this account
for the number of electric heaters etc put out in council
cleanups and taken to landfill tips? It’s too expensive to
call an electrician to replace a heater element but it’s so
easy to yourself – if you were allowed.
Even if you’ve been doing it for a lifetime, even if you
have a PhD in electrical engineering, unless you have an
Woops! We said theoretically . . . the sloppy painters missed
the wall – but got the switch plate! It is precisely situations
like this which call for the switch to be replaced if the
owner is at all house-proud. But it would probably cost you
at least $100 (or more!) to get an electrician to do the job!
siliconchip.com.au
electrician’s ticket, you can’t touch anything powered
by mains. In fact, it gets worse. You won’t be allowed to
build any mains-operated device if you follow the letter
of the law.
No more amplifiers, radios, lighting displays – in fact, no
thing powered by more than a battery or a plug-pack!
Needless to say, most hobbyists will continue to treat
this with the contempt it deserves. Wasn’t it Thomas Jefferson who once said (and we paraphrase somewhat) if a
law is stupid it is every citizen’s right to ignore or disobey
that law?
And the reason the bureaucrats and politicians give for
this stupidity? Why, safety, of course!
Of course, that’s utter rubbish. One wonders how all the
brilliant electrical inventions over the years would have
come about if this craziness had been on the statute books
since, say, Marconi’s time. And what of all the trades people,
technicians and professionals who cut their teeth on simple
projects, moving up to (perish the thought!) mains-powered
devices before embarking on their careers in the industry?
Where would they be today? Where would we be today?
Buying the bits
OK, so we’re going to assume that someone (no, not
you, of course!) is going to want to, say, change a power
outlet from a single to a double. Maybe put in a dimmer
or electric fan. Or even replace that old ceiling rose that’s
so old it’s dangerous.
Where do you (oops, sorry, they!) get the bits to do it?
Not so long ago, you could buy power outlets, light
switches, dimmers and a host of other electrical hardware
at virtually any supermarket. Not any more: today you
have to buy from either an electrical “wholesaler” or, more
likely, from a large hardware store. You’ll almost certainly
save money buying retail from a hardware store than buying wholesale because unless you have an account with
one of the wholesalers, the prices they will ask are often
ridiculous.
Most wholesalers work on the system of charging a certain
price on the “invoice” or sales docket (the one the electrical
contractor gives the customer to claim back purchases) but
when the wholesaler’s account is sent out to the contractor,
there is an often-quite-substantial discount applied. That
way, it “appears” that the contractor is supplying the goods
to the customer “at cost”, where in fact he ends up making
a substantial profit.
We’re not saying that is wrong or right – it’s another
fact of life.
Or you could go to electronics retailers such as Jaycar and
Altronics, both of whom stock a range of common D-I-Y
equipment such as power outlets, light switches and mains
cables – at very good prices. However, for such things as
conduit and the myriad of electrical fittings, the hardware
store is still the best bet.
Keeping it up-to-scratch
As we said before, it is (legally) impossible for an unlicensed person to do any electrical work and get it signed
off by an electrical contractor. But if you are doing any
work, you might as well do it “by the book”, if for no other
reason than, you guessed it, safety. Here we have no argument with the regulations which all electrical contractors
have to abide by. For the most part, they make perfect sense
siliconchip.com.au
Press Release
Electrical contractors and electricians will effectively be banned
from working on equipment operating at normal mains voltage
under a new guideline Code of Practice issued by EnergySafety.
The Code applies to electrical contractors and all electricians
working in general industry. It also places obligations on
contractors’ clients and all employers of electricians who request
that live work be performed,” Director of Energy Safety Albert
Koenig has said.
“Working on live electrical circuits and equipment or in very close
proximity to live parts is potentially dangerous and mostly places
the lives of electricians at risk needlessly,” Koenig said.
Loss of production, increased costs and operational inconvenience
will not be regarded as justifying live work.
Under the Code, live work will be justified only if there is a
greater risk of danger to lives of people using, or affected by, an
electrical installation, compared with risks incurred by electrical
workers asked to perform live work.
In such circumstances, a live work justification case, backed by a
formal risk assessment under the Code, must be made out by the
licensed electrical contractor’s client, requesting that live work be
carried out. In respect of residential type installations, the Code
never allows live work.
If the electrical employer is satisfied that live work is justified and
it can be carried out safely, a strict safety plan must be followed,
comprising:
•
The contractor must prepare a detailed work plan and
set of procedures, complying with the Code, to cover the
work;
•
All electrical workers involved in performing the work
must agree it can be done safely;
•
A competent and independent safety assessor must
approve plans and procedures if the prospective fault
current exceeds 10,000 amperes at the site in question;
•
An experienced safety observer must be present at all
times while the live work is under way and must have no
other duties while carrying out the observer role.
Koenig said the Code provided for routine activities which
generally need to be conducted while circuits are live, including
testing, commissioning and location of faults.
“With this Code, we are addressing a large number and variety of
situations where electrical contractors and electricians are placed
under commercial pressure by their clients to perform risky live
work, merely to hold costs down, keep production going and avoid
inconvenience,” he said.
He also noted that the guideline Code does not apply to the
electricity transmission and distribution related activities within
the electricity supply industry, as this sector has its own guidelines
for safe work practices.
EnergySafety is currently conducting a series of industry
presentations around the State at regional centres, to outline
recent electrical industry legislation and technical standards
changes, and this new Code.
June 2008 17
This old-style fuse box,
circa 1950, has most of
its plug-in fuses replaced
with circuit breakers. The
main switch (highlighted)
clearly shows whether
it is in the on or off
position. Contrast this
with the modern DIN rail
box below: its “master
isolator” (top left)
switches two phases. This
box has combined RCDs
and circuit breakers.
or plasterboard, creating an unsightly mess. It’s simple to
avoid this if you know how.
We said this is in a grey area because you aren’t actually doing any wiring installation or modifications. But
we have seen, time and again, warnings from electricity
authorities that you must not do this because, they say, it
is (a) dangerous and (b) illegal.
To (a) we say, with proper guidance , poppycock. To (b)
we will agree to disagree.
Anyway, temporarily loosening the switch or outlet
is less dangerous than replacing a light globe (they have
exposed mains pins, the bulbs break etc etc) – just as long
as you follow a few simple steps.
Here are those steps:
specifying the number of outlets on a circuit means less
chance of an overload and fire, for example.
So if you plan to do some electrical work, get yourself
a copy of the SAA Wiring rules which explain in detail
what you can and cannot do. You’re more likely to find
them described as “AS/NZS3000” You can get an on-line
(PDF) version for just under a hundred dollars – expensive,
yes; but at least you’ll know what is required (see www.
SaiGlobal.com/wiringrules). You may also be able to find
a copy at a major library.
(1) Turn the power off at the main switch (or, if you can
positively identify which circuit the outlet/switch is on,
by flipping the circuit breaker or removing the fuse).
(2) Test that you have indeed turned the power off using
a non-contact voltage indicator. One of these devices should
be in every handyman’s toolbox. They’re not expensive
and are much better than the old neon test screwdriver,
which does require contact with the live circuit (see panel
on P13). Only if you are absolutely sure that the power is
cut off, proceed to step 3.
(3) Many modern outlets and full-size switches (such
as HPM’s “Excel” range and Clipsal’s “2000” series) have
a clip-on cover plate over the actual outlet/switch. This
is very easily removed by sliding a sharp knife under the
edge and prising the cover plate off.
Older power points and switches simply have two screws
Let’s get down to it
In this first instalment, we’re going to describe how to
do something that, legally, is arguably in a “grey” area:
temporarily pulling a light switch or power outlet out
from the wall or architrave so that you can paint behind it.
“Too easy”, you say. Oh yeah? How then do you account
for the millions of light switches and power outlets in
homes and offices with paint around the edges! And, just
as importantly, the number of damaged walls around outlets
(or switches/architraves) where the offending device has
pulled away paint or even the outer layer (skin) of Gyprock
18 Silicon Chip
It’s an all-too common sight: someone has removed the
light switch and taken a chunk of paint with it. It’s easy to
avoid this problem . . . but is it legal? Incidentally, whoever
removed this light switch obviously didn’t bother to insert
the plastic “pips” to cover the screws.
siliconchip.com.au
This light switch is certainly not “dead” – the non-contact
tester is glowing red and singing its head off! As you can
see, these devices work quite happily from the front of the
outlet/switch so you can test them before you do anything!
Having turned off the main switch, turned off the
appropriate circuit breaker (or removed the fuse) and then
checked again that it is dead, cut a thin line right around
the outlet/switch to make sure you don’t remove any paint.
holding them in, usually covered by two small flushmounting plastic “pips” which have to be removed before
you can access the screws. It is possible to lever them out
without damage, so they can be re-used, by using a sharp
knife or tiny screwdriver. However, they are replaceable
(hardware stores usually have them) so most times they are
simply dug out with a screwdriver and discarded.
(4) Whether you have an outlet/switch with a cover plate
or without, before you undo any screws, use a very sharp
knife (a craft knife is best, a box-cutter will do at a pinch)
to score around the outlet or switch, using the outlet or
switch as a template. The idea is to cut a very thin line
through the paintwork underneath so that when you do
remove the outlet/switch, it doesn’t adhere to the paint
and pull some away.
(5) Undo the screws holding the switch/outlet in
place moving back and forth between the screws, a little
at a time. You should find that if your cut (in 1 above) is
deep enough, the outlet will be able to be prised off the
paintwork without damaging it. It’s quite possible, indeed
likely, that the paintwork underneath the switch/outlet
will be damaged but if you replace the switch/outlet in
exactly the same position, you won’t see it. You may not
even need to remove the outlet/switch completely – just
as far as necessary to reach behind it to paint.
If you do remove the screws completely, don’t pull it out
any further than you need to and don’t place any strain on
the cabling (especially if it is old!).
(6) With the outlet/switch out of the wall/architrave,
temporarily run a couple of layers of electrical insulation
tape (or Gaffer tape, which sticks better to dusty surfaces)
around ALL of the back of the outlet/switch, making sure
that you cover any connection points and screws and the
wires going into them.
Having said that, try to avoid moving the outlet/switch
any more than you have to. Wiring, particularly old wiring, is often brittle.
(7) With the tape in place, you can restore power if
necessary and start painting. Remember that water-based
(acrylic) paint is conductive so avoid getting too close to
the switch parts, even if the power is turned off and even
if you have covered it in tape.
Replacement is simply the reverse of these steps, with
restoring power the very last thing!
SC
This step – wrapping the back of the switch or outlet in
insulation tape of masking tape – really is a “belt and
braces” approach but is one which ensures your safety.
Wet paint is conductive, so you want to be sure, to be sure!
Finally, screw the switch/outlet back in just far enough to
ensure that you can paint behind it without getting paint
on the plate (as numerous painters have obviously done
here!) When touch dry, screw it all the way back in.
siliconchip.com.au
June 2008 19
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