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#173766 - 01/17/08 07:28 PM Question on Australian outlets
wa2ise Offline
Member

Registered: 11/29/02
Posts: 771
Loc: Oradell NJ USA
Back a little more than twenty years ago, I took a vacation and was part of a tour group to see Australia and Haley's Comet back in 1986. We also visited Cains, Alice Springs and Ayer's Rock, Melborne and Sydney. And along with the usual souvineers I bought an Australian wall outlet, and plug that goes with it. Was just looking at it closely, and noticed that the mounting holes look to match American electrical boxes, 3 1/4 inch apart, and the outlet came with what looks like number 6 screws. Question: I also noticed where the connections on teh back, set screws going into metal cups. I would guess that one inserts the stripped wire into the appropriate cup/hole, and tighten the set screw. Thing is, the cup / hole is very big, about 5 mm diameter. Looks like the wire is to be inserted into something else, that then in turn is inserted into these big cup / holes, yes? So one could replace a bad outlet and not get the wires mixed up? The outlet's construction could let you get the hot (220V!) on the ground, and it wouldn't get shorted to the electrical box and earth/ground via conduict or earth/ground wire.

The outlet has built in switches that would shut the hot off, one per socket. But there's no interlock to prevent someone from plugging something in while the socket is hot.


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#173777 - 01/18/08 12:19 AM Re: Question on Australian outlets [Re: wa2ise]
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
 Originally Posted By: wa2ise
Question: I also noticed where the connections on the back, set screws going into metal cups. I would guess that one inserts the stripped wire into the appropriate cup/hole, and tighten the set screw. Thing is, the cup / hole is very big, about 5 mm diameter. Looks like the wire is to be inserted into something else, that then in turn is inserted into these big cup / holes, yes? So one could replace a bad outlet and not get the wires mixed up? The outlet's construction could let you get the hot (220V!) on the ground, and it wouldn't get shorted to the electrical box and earth/ground via conduit or earth/ground wire.

The outlet has built in switches that would shut the hot off, one per socket. But there's no interlock to prevent someone from plugging something in while the socket is hot.


Hi WA2ISE,
Actually what you have struck is a socket-outlet with Tunnel Terminals.
If you are terminating a single wire into that terminal, you have to (depending upon the wire size you are using), either twist the strands of the wire together and then bend the wire back on itself, to form a 7mm "loop", it is not acceptable to have bare wire outside of the terminal.
If there are 2 wires going into the same terminal, you twist them together (carefully) and do up the screw.
If you've ever used them you would know, they are a LOT simpler and easier to use than wrap the wire around the screw, they are almost idiot-proof.

As for the connection markings, there would normally be a P, N and E marking as part of the connection plate, that's all that would have been needed back then as all electrical work was required to be done by a Qualified Electrician,
no question.
All socket-outlets these days use a colour-coding system.

With respect to the interlock issue, there are actually safety shutters in newer outlets, things have progressed Down Under, you cannot get a single object into a socket here unless it has 2 pins to open the shutter mechanism.

{BTW, I'll get some pics of how the wire preparation/termination is done correctly for the US Members here}


Edited by Trumpy (01/18/08 12:35 AM)
Edit Reason: Add last bit
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#173780 - 01/18/08 03:25 AM Re: Question on Australian outlets [Re: Trumpy]
32VAC Offline
Member

Registered: 06/28/04
Posts: 203
Loc: Alice Springs, NT, Australia
The beauty about the tunnel terminals used on the newer outlets is the ability to fit up to four 2.5mm2 wires into one terminal. Older outlets could take maybe 2 2.5mm2 wires easily.

As seen in my travels the other day, an outlet for a pump around 50 metres from the board was done in 6mm2 wire, the outlet took this wire with no problems which may be a task on an outlet with screw terminals (I'll try it later, I have some 6mm2 offcuts and some "CIRCLE F" 125V 15A switched outlets in the shed, let you all know how I get on with this experiment)

The 6/32 screws are still in use here to mount outlets, some people try to use M3.5 with not too much luck...

The colour coding for the screw tunnels is red for Active, Green for Earth and the nuetral has no colour coding ( most, if not all outlet mechanisms are black in colour). This is done with small coloured dots or more recently as ink applied to the entrance to the cable tunnels.

The 84mm mounting centres do match the American spacings to witin a millimetre sometimes closer. In my shed I have Circle F brand outlets mounted onto Clipsal mounting blocks.

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#173822 - 01/19/08 02:23 PM Re: Question on Australian outlets [Re: 32VAC]
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
I'm assuming from the description and the photos I've seen that these "tunnel" terminals are pretty much the same as the ones used on British fittings?

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#173828 - 01/19/08 05:33 PM Re: Question on Australian outlets [Re: pauluk]
32VAC Offline
Member

Registered: 06/28/04
Posts: 203
Loc: Alice Springs, NT, Australia
Wire goes in the tunnel, screw clamps down from one side onto the wire/s in the tunnel, termination completed.

Picture below shows the tunnels & the wire strip guage to remove the correct length of insulation.





Edited by 32VAC (01/19/08 05:38 PM)

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#173861 - 01/21/08 01:04 AM Re: Question on Australian outlets [Re: 32VAC]
Texas_Ranger Offline
Member

Registered: 12/17/01
Posts: 2343
Loc: Vienna, Austria
Tunnel terminals were once fairly common for switches (rarely for sockets) but were replaced by compression plate terminals by the mid 1960s. Sockets mostly had simple screw terminals, better versions with guards on either side of the screw so the wire can't slip out without bending a hook or better ones compression plate. Both versions were in use until the 1980s when push-in terminals became popular and eventually replaced all screw terminals.

As far as I know none of those terminals ever fit more than 2 wires of any cross section properly... some people did manage to squeeze in 4 1.5mm2, but they're only listed for 2.

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#173921 - 01/22/08 10:59 PM Re: Question on Australian outlets [Re: Texas_Ranger]
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
 Originally Posted By: Texas_Ranger

As far as I know none of those terminals ever fit more than 2 wires of any cross section properly... some people did manage to squeeze in 4 1.5mm2, but they're only listed for 2.

Good point, Ragnar.
I note that the terminals on the newer PDL (brand) sockets are considerably smaller than they used to be.
Now, you'd be lucky to get 2 2.5's into the terminals and this to a point annoys me somewhat, the reason being, while Mr Home-owner is trying to wire his new shed, he twists the wires up together as tight as he can until they fit.
What he may not know, that his pliers have chewed off quite a bit of the copper on the outside of the outer strands of the twist, or if he is really intent on getting the wires in there, he may even end up breaking the strands with excess pressure on the plier jaws.
Using pliers is something that needs to be done gently.
_________________________
Let's face it, these days if you're not young, you're old - Red Green grin

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#173925 - 01/23/08 01:02 AM Re: Question on Australian outlets [Re: Trumpy]
Texas_Ranger Offline
Member

Registered: 12/17/01
Posts: 2343
Loc: Vienna, Austria
Indeed, stranded wire would even aggravate the problem - here any building wire is solid up to 6mm2. Usually only DIY hack jobs use stranded wire for permanent wiring (extension cord stapled to the wall surface).

The best bet if you have more than two wires to connect is to get the splices out of the back box into a splice box. 67mm diameter 50mm deep boxes with Schuko receptacles can't take much more - if you're really lucky you can fit 3 Wago connectors back there but I'd never try it myself.

I've seen one guy who hacked a 100mm deep hole into an exterior brick wall and put in a splice box behind the back box of the sockets... might even have worked if he had bothered to take out the entire back of the box and not only a small section too small to get the choc blocks out of the splice box... I ended up putting in a splice box above the socket. That was a bad one... feed to the sockets (twin socket), feed to another socket, feed to two wall lights and the travelers of a 2-way circuit...

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#173928 - 01/23/08 02:39 AM Re: Question on Australian outlets [Re: Texas_Ranger]
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
The terminals in the photo above look just like many British terminals. Some of the higher-priced makes (e.g. MK) use a little compression plate on the end of the screw to clamp down on the conductors.

The terminals on British 13A sockets are generally designed to allow for up to three 2.5 sq. mm conductors (permitting a spur cable to be run off a ring from a socket), but there's quite a variation in the size and the design of the surrounding plastic. Some are really a bit of a squeeze for three conductors, while others will take four 2.5s without too much trouble.

Standard "T&E" residential cable here is solid up to the 2.5 size, then stranded for 4 mm and above. Conduit singles are available in both solid and stranded for the 1.5 and 2.5 sizes.

Some cheap sockets skimp on the size of the earth terminal though (where it's an exposed terminal fitted on the metal strap rather than being the same type as the L and N terminals). I've seen some where even two 2.5 stranded conductors is a tight fit.

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#174044 - 01/25/08 01:45 PM Re: Question on Australian outlets [Re: pauluk]
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
Paul,
I've struck solid 2.5mm here a few times in houses built or re-wired during the 60's.
I think that the first white sheathed TPS (Tough Plastic Sheathed) cables that came out here were all solid or the cable was imported from the UK.
Stranded cables make the task of terminating wires a lot easier, especially where there is more than one wire in a terminal.
Oddly enough, I happened to strike some 1 mm stranded TPS in a house here recently, I didn't like the look of it either, it looked really cheap and shonky.
_________________________
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