View source for AS/NZS 3112

{{Short description|AC power plug and socket used in Australia and New Zealand}}
{{Use Australian English|date=April 2014}}
{{Use dmy dates|date=January 2020}}
[[File:Aust AC plug.jpg|thumb|150px|Australasian standard three pin plug, with part insulation on the Active/Line and Neutral pins.]]

'''AS/NZS 3112''' is the harmonised Australian and New Zealand Standard for [[AC power plugs and sockets|AC power plugs (male) and sockets (female)]]. The [[International Electrotechnical Commission]] (IEC) "world plugs" website defines this design as '''Plug Type I'''. The plug consists of two flat pins forming an inverted V-shape, plus a vertical earthing pin below of a slightly longer length. [[Appliance classes#Class II|Double insulated]] appliances may omit the earth pin. When viewing a plug from the rear, and the earth pin downwards, the top left pin is active and the top right pin is neutral. The shank of the active and neutral pins of every 10 [[Ampere|amp]] and 15 amp flat-pin plug sold after 3 April 2005 are required to be insulated, in accordance with AS/NZS&nbsp;3112:2000.<ref>{{cite web |url=http://www.ji.com.au/insulatedlivepins/ |title=Insulated Live Pins :: Jackson Industries |work=ji.com.au |accessdate=19 April 2017 }}</ref>

Since 2000, the nominal [[voltage]] in most areas of Australia has been 230&nbsp;V,<ref name="ReferenceA">AS60038-2012 [[Standards Australia]] – ''Standard Voltages''</ref><ref>[http://electricalconnection.com.au/article/10017796/when-voltage-varies When voltage varies]. Electrical connection (22 October 2012). Retrieved on 24 May 2014.</ref><ref>[https://www.powerlogic.com.au/Attachments/Voltage%20and%20Equipment%20Standard%20Misalignment%20PaperV.pdf VOLTAGE & EQUIPMENT STANDARDS MISALIGNMENT]</ref> except for Western Australia, which remains at 240&nbsp;V, and Queensland, which transitioned to 230&nbsp;V in 2020. In New Zealand, the voltage is 230 V. Fiji, Tonga and Papua New Guinea remains at a nominal 240&nbsp;V, and in the Solomon Islands it is 220&nbsp;V. The standards of China and Argentina also use the Type I plug and socket, though the live (active) and neutral pins are swapped in Argentina, and neither includes insulation on these prongs. In both countries the voltage is 220&nbsp;V, and the outlet is mounted upside-down with the earth pin at the top for safety. Differences in voltage may give rise to compatibility issues, especially for travellers and those purchasing appliances overseas or online. Most 230&nbsp;V equipment will work with a supply voltage in the range 220–240&nbsp;V without issues. The [[utility frequency|mains frequency]] is 50&nbsp;Hz in all these countries. Over time, Pacific Island countries that use AS/NZS standards will also transition to the newer voltage of 230&nbsp;V.{{or|date=January 2025}}

The standard is used in Australia, New Zealand, [[Fiji]], [[Tonga]], [[Solomon Islands]], [[Papua New Guinea]] and several other Pacific island countries. In Argentina and China an almost-identical design is also used, but these are separate standards, despite their appearance.

== History ==
[[File:Americanaussieoutlet.jpg|thumb|right|150px|Now obsolete American 3-pin duplex socket-outlet]]

Australia's standard plug/socket system was originally codified as standard C112 (floated provisionally in 1937, and adopted as a formal standard in 1938). The Australian standard of 1937 was the result of a "gentlemen's agreement", reportedly from 1930, between manufacturers Fred Cook of Ring-Grip, Geoffrey Gerard of Gerard Industries and Brian Harper Miller of the State Electricity Commission of Victoria (SECV).<ref>{{Cite web|url=http://members.iinet.net.au/~cool386/plug/plug.html|archive-url = https://web.archive.org/web/20191019051558/http://members.iinet.net.au/~cool386/plug/plug.html|archive-date = 19 October 2019|title = The origins of the Australian plug}}</ref><ref>{{cite web|url=https://www.ewh.ieee.org/r10/nsw/subpages/history/aust_power_connectors.pdf |title=Electrical Power Connector Overview in Australia |website=[[IEEE]] |access-date=19 April 2017}}</ref> The design was based on [[History of AC power plugs and sockets#American 125 V, 15 A / 250 V, 10 A "Australian" style|an American plug and socket-outlet first intended for use at 120&nbsp;V]] which was patented in 1916 under {{US Patent|1,179,728}} by [[Harvey Hubbell]].<ref>{{cite web|url=http://pdfpiw.uspto.gov/.piw?Docid=1179728&idkey=NONE&homeurl=http:%252F%252Fpatft.uspto.gov%252Fnetahtml%252FPTO%252Fpatimg.htm |title=Patent Images |work=uspto.gov |access-date=19 April 2017}}</ref> By the early 1930s this design had been up-rated to 250&nbsp;V 10&nbsp;A capacity and Hubbell had supplied the Australian electrical industry with his sockets.<ref>{{Cite web|url=https://www.plugsocketmuseum.nl/NorthAm3.html#AU-NZ|title=Museum of Plugs and Sockets: Origin of US plug}}</ref> Current Australian plugs fit these American outlets perfectly. (While this socket-outlet never became a [[NEMA connector|NEMA]] standard design, the 50&nbsp;A NEMA&nbsp;10-50R, has a similar pin configuration in a larger form.<ref>{{cite web |url=http://www.frentzandsons.com/Hardware%20References/plugandreceptacleconfiguratio.htm |title=Plug and Receptacle Configurations: NEMA Straight Blade Plugs and Receptacles |website=Frentz & Sons Hardware |access-date=21 January 2016 |archive-url=https://web.archive.org/web/20030116080902/http://frentzandsons.com/Hardware%20References/plugandreceptacleconfiguratio.htm |archive-date=16 January 2003 |url-status=dead |df=dmy-all }}</ref>) [[Argentina]], [[Uruguay]] and [[China]] based their plugs and sockets on the same design. New Zealand also adopted the Australian design, since Australian equipment and many electrical appliances were exported to that country.

One of the reasons behind the adoption of that particular design was that it was cheap to make, with the flat pins being able to be easily stamped out of sheet brass, in contrast to round pins or thicker rectangular ones used in other countries. This was also a consideration when the Chinese authorities officially adopted the design in relatively recent times, despite the considerable inroads the British plug had made, because of its use in [[Hong Kong]]. The Chinese socket is normally mounted with the earth pin at the top. This is considered to offer some protection should a conductive object fall between the plug and the socket.<ref>{{Cite web|url=http://www.plugsocketmuseum.nl/Australian1.html|title = Museum of Plugs and Sockets: Australasian types}}</ref><ref>{{cite web|url=http://www.electrical-contractor.net/forums/ubbthreads.php/topics/143392/History_of_the_Australian_plug.html|title=History of the Australian plug|work=electrical-contractor.net|access-date=19 April 2017}}</ref> The Chinese [[CPCS-CCC]] (Chinese 10&nbsp;A/250&nbsp;V) plugs and socket-outlets are almost identical, differing by only {{cvt|1|mm}} longer pins<ref name=stayonline>{{cite web |url=http://www.stayonline.com/reference-international-plugs.aspx |title=International Standards Reference Chart |website=stayonline.com |date=20 January 2016}}</ref> and installed "upside down". Though AS 3112 plugs will physically connect, they may not be electrically compatible to the Chinese 220&nbsp;V standards. Originally there was no convention as to the direction of the earth pin. Often it was facing upwards, as socket-outlets in China now do but it could also be downwards or horizontal, in either direction.<ref>{{cite web |url=http://members.iinet.net.au/~cool386/plug/plug.html |title=The origins of the Australian plug |first=John |last=Hunter |work=iinet.net.au |access-date=19 April 2017 }}</ref>

In Australia, the C112 standard was superseded by AS&nbsp;3112 in 1990. A major update was released in 2000 as AS/NZS&nbsp;3112:2000, which mandated active and neutral insulated pins<ref>{{cite web|url=http://www.commerce.wa.gov.au/sites/default/files/atoms/files/insulated_pins_on_plug_tops_0.pdf |title=Pins on plug tops |website=Commerce.wa.gov.au |access-date=19 April 2017}}</ref> on the plugs sold for use with these socket-outlets after 3 April 2005. This significantly reduces the risk of electric shock from accidentally touching the pins of a partially inserted plug. The standard AS/NZS 3112:2004 introduced more stringent testing procedures to test for bending of the pins and subtle changes to the radius of the pin tips. The current version is AS/NZS&nbsp;3112:2017.<ref>{{cite web |title=AS/NZS 3112:2017: Approval and test specification – Plugs and socket-outlets |url=https://www.standards.govt.nz/shop/asnzs-31122017 |website=Standards New Zealand |access-date=30 March 2025 |date=24 August 2017}}</ref>

== Description ==
<!-- Text taken from [[Domestic AC power plugs and sockets]] -->
[[File:Dual 3 Pin Power Outlet - Construction.jpg|right|thumbnail|Dual 3-pin socket-outlet construction]]
[[File:Australian Dual Socket Outlet.jpg|thumb|left|150px|Switched dual 3-pin socket-outlet]]
[[File:Australian "Quick Connect" (Dual) Power Outlet.jpg|thumbnail|right|Socket-outlet, using insulation displacement as a means of connecting to low voltage (230&nbsp;V) supply conductors]]

AS/NZS&nbsp;3112 compliant plugs have two flat pins forming an inverted V-shape plus a vertical earthing pin. The flat blades measure {{convert|6.35|by|1.6|mm|in|frac=16|abbr=on}} with the active (line) and neutral pins {{convert|17.35|mm|in|frac=16|abbr=on}} long set 30° to the vertical and the vertical earth pin being {{convert|20|mm|in|3|abbr=on}} in length.<ref name=Yunhuan>{{cite web|url=http://yunhuanelectric.com/Clkj_Images/upfile/b/Australia-AS-NZS-3112-Plug-Drawing.pdf |title=AS/NZS 3113 plug drawing |publisher=Ningbo Yunhuan Electric Group Co., Ltd. |accessdate=20 January 2016 |url-status=dead |archiveurl=https://web.archive.org/web/20160206014158/http://yunhuanelectric.com/Clkj_Images/upfile/b/Australia-AS-NZS-3112-Plug-Drawing.pdf |archivedate=6 February 2016 }}</ref> The pins are arranged at 120° angles around a common midpoint, with the active and neutral centred {{convert|7.92|mm|in|frac=16|abbr=on}} from the midpoint, and the earth pin centred {{convert|10.31|mm|in|frac=16|abbr=on}} away.<ref name=Yunhuan/>

A standard socket-outlet provides a nominal RMS voltage of 230 volts<ref name="ReferenceA"/> at a maximum of 10 amps and always includes an earth connection. "Shuttered" socket-outlets are available, but these are not required by regulation.

There are unearthed versions of the plug used with this outlet having only the two flat inverted V-aligned pins, without the earthing pin. Such plugs are only to be used for devices where other safety standards are in use (e.g. double insulation). They are not available separately but only integrally with [[power cord]]s specifically designed for the purpose.

A view of the wiring side of a typical dual socket-outlet is also shown on the right, together with an annotated view of the mechanism, without the front cover. (One "rocker" switch has been disassembled to show its operation.)

If required, such dual socket-outlets can be obtained (at additional cost) using [[insulation displacement]] as a means of connecting to the supply conductors, as can be seen in the illustration – below right.<ref>{{cite web |url=http://updates.clipsal.com/ClipsalOnline/Files/Brochures/A0000102.pdf |title=Quick Connect |website=Updates.clipsal.com |accessdate=19 April 2017 |archive-date=28 September 2021 |archive-url=https://web.archive.org/web/20210928215005/https://updates.clipsal.com/ClipsalOnline/Files/Brochures/A0000102.pdf |url-status=dead }}</ref><ref>{{cite web|url=http://www.clipsal.com.au/trade/downloads/videos|title=Clipsal Videos |work=clipsal.com.au|accessdate=19 April 2017|archive-url=https://web.archive.org/web/20131214075053/http://www.clipsal.com.au/trade/downloads/videos|archive-date=14 December 2013|url-status=dead}}</ref> The benefits claimed for their use in these applications include up to 50% faster installation, due to the reduction in the stripping, twisting and screwing down processes.

{{Clear|left}}<!-- Push next section heading down so it comes after the previous section's left-floating images -->

== Switch requirements ==
[[File:Australian Socket-Outlet, Auto Switched.jpg|thumbnail|left|Socket-outlet, auto switched by plug insertion. Automatically switched socket-outlets such as these may be used to supply power to refrigerators, some computers and other accessories that normally should not be switched off. The absence of a user operable switch prevents the accidental switching off of such devices]]
[[File:Australian Surface Socket-Outlet and Plug.jpg|thumbnail|right|Surface socket-outlet and plug.]]

Regulations require socket-outlets to be "individually controlled by a separate switch that ... operates in all active conductors",<ref>AS/NZS 3000:2007 (Wiring Rules) – 4.4.4.1</ref> subject to three "exceptions":

<!-- This div fixes the bullet list not being indented when there's a floating image on the left -->
<div style="display: inline-block; width: 65%;">
* "A single switch may be used for the control of two socket-outlets located immediately adjacent to each other". (subject to the current rating of the switch to be at least equal to the (a) total current rating of the sockets concerned; or (b) the current rating of the overcurrent protection device concerned, whichever is the lesser value.)<ref>AS/NZS 3000:2007 (Wiring Rules) – 4.4.4.2</ref>
* "A socket-outlet that is switched by the insertion and withdrawal of the plug shall be deemed to meet the requirements&nbsp;...." (Such a socket-outlet and the mechanism used is shown on the left.)
* "A socket-outlet that is rated at not more than 10&nbsp;A, installed for the connection of a fixed or stationary appliance or a luminaire and that is not readily accessible for other purposes, need not be controlled by a switch". (Such a socket-outlet and plug, installed in a ceiling space, is shown below to the right.)
</div>

However, "stationary appliances" (such as fans) and most "luminaires" may be controlled by a remote switch, which would switch the supply via the socket-outlet concerned. Exceptions could be devices such as illuminated "Exit" signs, which require connection to the power supply at all times.

Each switch or means of operating a switch, for a socket-outlet shall be (a) as close as practicable to the socket-outlet, and (b) marked to indicate the socket-outlet(s) or the connected electrical equipment that it controls, with the exception that marking is not required where the socket-outlet controlled is obvious because of the location of the switch.<ref>AS/NZS&nbsp;3000:2007 (Wiring Rules) – 4.4.4.3</ref>

Double pole switches are required in caravans and mobile homes:
<div style="display: inline-block; width: 65%;">
* All switches installed in transportable structures and intended to be connected to the site supply shall operate in all live (active and neutral) conductors."<ref>AS/NZS&nbsp;3001:2008 (Electrical Installations – Transportable structures and vehicles) – 3.6.2</ref>
* Switches that directly control socket-outlets shall comply with the above requirements."<ref>AS/NZS3001:2008 (Electrical Installations – Transportable structures and vehicles) – 3.6.3.1</ref>
</div>

{{Clear|left}}<!-- Push next section heading down so it comes after the previous section's left-floating images -->

== Variants ==
[[File:Australian mains socket styles for different current ratings.jpg|thumbnail|left|Australian mains socket outlets for different current ratings.

Starting with the basic 10&nbsp;A socket outlet, the width of the earth pin is first increased, the width of the Line and Neutral pins are then increased and the shape of the earth pin is then changed, permitting only plugs of an equal or lesser current rating to be inserted into any socket outlet.]]
[[File:Australian 32 A vs 10 A mains plug.jpg|thumbnail|right|Comparison of 32&nbsp;A (left) and 10&nbsp;A (right) plugs.]]

Standard single phase 230&nbsp;V domestic socket outlets in Australia and New Zealand are rated at 10&nbsp;A.

However, for heavier duty applications there are several variants having current ratings of up to 32&nbsp;A:
<!-- This div fixes the bullet list not being indented when there's a floating image on the left -->
<div style="display: inline-block; width: 65%;">
* The 15&nbsp;A outlet has a wider earth pin than the 10&nbsp;A outlet.
* The 20&nbsp;A outlet has a wider earth pin and wider Line and Neutral pins.
* The 25&nbsp;A outlet has an inverted L-shaped earth pin and wider Line and Neutral pins.
* The 32&nbsp;A outlet has a sideways U-shaped earth pin and wider Line and Neutral pins.
</div>

From this it may be seen that any plug can be inserted into a socket outlet of the same or higher rating but cannot be inserted into a socket outlet of lower rating.

Hence, a 10&nbsp;A plug will fit into all of the five types of socket outlets, a 15&nbsp;A plug will fit into all except a 10&nbsp;A (and so on) while a 32&nbsp;A plug will fit only into a 32&nbsp;A socket outlet.

In general, only 10&nbsp;A and 15&nbsp;A socket outlets are likely to be encountered in domestic or commercial installations. Higher rated socket outlets are sometimes used for connection of electric ovens in domestic kitchens. These sockets are rarely seen in industrial environments, where [[AS/NZS&nbsp;3123]] weather-proof sockets are generally preferred.

A variant of the Australian standard 10&nbsp;amperes plug has a socket on the back to allow connection of a second appliance to the same outlet. This type of plug is known officially as a "socket adapter plug" but is referred to colloquially, in Australia, as a "piggy-back plug", or in New Zealand, as a "tap-on" plug and is shown below to the right. In Australia the plug is now available only as part of a pre-assembled extension cord, or by special order. In New Zealand re-wireable PDL 940 "tap-on" plugs are more widely available.

[[File:Socket Adaptor Plug.jpg|thumb|Socket Adapter Plug]]
[[File:Socket with round earth connector.jpg|thumb|Socket with a round earth pin]]
Other variants include plug/sockets with a rating of 10&nbsp;A using a round earth pin, which is used on "special use" circuits, such as [[storage heater]]s in classrooms; and a 110&nbsp;V 10&nbsp;A version that has round active & neutral pins with a flat earth pin. The latter is rated at only 110&nbsp;V (since certain [foreign] 110&nbsp;V plugs could be inserted into the socket-outlet) and may be used on [[Parabolic aluminized reflector light|PAR 64 lights]], where two 110 volt 1000 watt lamps are used in series.<ref>{{cite web |url=http://updates.clipsal.com/clipsalonline/Files/Brochures/A0000123.pdf |title=Plugs, Sockets and Adaptors Technical Data – 621471 |website=Updates.clipsal.com |accessdate=19 April 2017 }}</ref>

The active terminal is the first 'socket' from the earth 'socket' in a clockwise direction when viewing the front of a socket-outlet. Care should be taken if Argentinian standards or faulty wiring swaps the active and neutral pins. Care should also be taken with the 10&nbsp;A version with the round pin as physically compatible, but electrically incompatible [[NEMA connector|NEMA&nbsp;7–15]] connector used for 277&nbsp;V 15&nbsp;A connections is encountered in commercial or industrial settings in the Americas.<ref>{{cite web|url=http://www.stayonline.com/reference-nema-straight-blade.aspx|title=NEMA Straight Blade Reference Chart|work=stayonline.com|accessdate=19 April 2017}}</ref>

While never "codified", since the 1960s it has become "normal" for socket-outlets manufactured for use in Australia/New Zealand to have the earth pin facing downwards, so that the longer earth pin will be the last to lose contact if the inserted plug is tugged downwards. Many products such as "side-entry" plugs (with the cord exit in the 5 o'clock/135-degree position) and extra low voltage "plug packs" are manufactured for use in Australia/New Zealand assuming that the socket into which they will be inserted has the earth pin downwards.

== Voltage ==

In 1980, the [[International Electrotechnical Commission]] (IEC) rationalised the 220&nbsp;V and 240&nbsp;V nominal voltage levels around the world to a consistent 230&nbsp;V. This rationalisation was ostensibly made to improve the economics of making appliances by allowing manufacturers to produce a range of items with a rated voltage of 230&nbsp;V. Not all countries have yet converted to the new standard.

The nominal voltage in most areas of Australia had been set at 240&nbsp;V in 1926. In 2000, [[Standards Australia]] issued a system Standard AS60038, with 230&nbsp;V as the nominal voltage with a +10% to −6% variation at the point of supply, i.e., 253&nbsp;V to 216.2&nbsp;V. A new power quality standard, AS&nbsp;61000.3.100, was released in 2011<ref>[http://infostore.saiglobal.com/store/Details.aspx?ProductID=1504005 AS 61000.3.100-2011 Electromagnetic compatibility (EMC) – Limits – Steady state voltage limits in public electricity systems], [[Standards Australia]], 2011</ref> that details additional requirements. The new standard stipulates a nominal 230&nbsp;V, and the ''allowable'' voltage to the customer's point of supply is, as mentioned, +10% to −6%. However, the ''preferred'' operating range is +6% to −2%. (244&nbsp;V–225&nbsp;V).<ref>{{cite web|url=http://electricalconnection.com.au/article/10017796/when-voltage-varies|title=When voltage varies - Electrical connection |work=electricalconnection.com.au|date=22 October 2012 |access-date=19 April 2017}}</ref>

In Australia, the actual voltages delivered to customers is set at the state/territory level. As of 2022, all states/territories have transitioned to 230&nbsp;V standards.<ref>{{Cite web |title=Full list: Plug, socket & voltage by country – World Standards |url=https://www.worldstandards.eu/electricity/plug-voltage-by-country/ |access-date=2022-03-16 |website=WorldStandards |language=en-GB}}</ref> Queensland began the transition to 230&nbsp;V in 2017.<ref name="dnrme">{{cite web |url=https://www.dnrme.qld.gov.au/energy/initiatives/statutory-voltage-limits |title=New statutory voltage limits for Queensland {{!}} Department of Natural Resources, Mines and Energy |website=www.dnrme.qld.gov.au |url-status=dead |archive-url=https://web.archive.org/web/20180314205529/https://dnrme.qld.gov.au/energy/initiatives/statutory-voltage-limits |archive-date=2018-03-14}} </ref> The reason given for Queensland's decision to move was the increased use of grid-tied rooftop solar installations raising the grid voltage. By lowering the voltage to 230&nbsp;V, additional headroom of 960 megawatts was created to accommodate future residential power generation from rooftop solar.<ref name="dnrme"/>

The voltage in Fiji, Tonga and Papua New Guinea is still 240&nbsp;V. In China, the Solomon Islands and Argentina the voltage is 220&nbsp;V.

== References ==

{{refs}}

== External links ==
{{commonscat}}

* [https://www.ewh.ieee.org/r10/nsw/subpages/history/aust_power_connectors.pdf Electrical Power Connector Overview in Australia]

[[Category:Mains power connectors]]
[[Category:Standards of Australia and New Zealand]]