IEC connector

IEC connector is the common name for the set of thirteen line sockets (called the "connector" in the specification) and thirteen panel plugs (called the "inlet") defined by International Electrotechnical Commission (IEC) specification IEC 60320 (formerly IEC 320). When used with no other qualifiers, "IEC connector" usually refers specifically to the C13 and C14 connectors.

Some types also come in line plug and panel socket versions to use as outlets but these are less common. They include two and three-conductor plugs of various current capacities and temperature ratings, all designed specifically for the purpose of attaching a mains power cord to a piece of equipment. Allowing an interchangeable mains power cord makes it very easy for equipment manufacturers to sell their equipment anywhere in the world as long as their equipment can operate on both 120/240 volt, 50/60 Hz mains power.

Appliance Classes

In addition to being grounded or not, these plugs are differentiated according to their IEC protection class.

Class 0 appliances have no protective-earth connection and feature only a single level of insulation.

Class I appliances must have their chassis connected to electrical earth.

Class II double insulated electrical appliances have been designed in such a way that they do not require a safety connection to electrical earth.

Class III appliances are designed to be supplied from a SELV (Separated or Safety Extra-Low Voltage) power source.

C13 and C14 connectors

Most desktop personal computers use the ten-amp panel-mounting C14 inlet to attach the mains cord to the power supply, as do many monitors, printers and other peripherals. Many older computers also provide a panel-mounting C13 outlet for powering the monitor. In AT form factor computers this outlet was controlled by the physical power switch. With the arrival of ATX the outlet was usually permanently powered, if present on the chassis.

A three-conductor cord with a suitable power plug for the locality in which the appliance is used on one end and a C13 line socket on the other is commonly called an "IEC cord." IEC cords are used to power many other pieces of electronic equipment other than computers, for example instrument amplifiers and professional audio equipment.

Cables with a C14 plug at one end and a C13 line socket at the other are commonly available, these are nearly always un-fused. They have a variety of common uses including connecting power between older PCs and their monitors, extending existing power cords, connecting to C13 socket strips (commonly used with rackmount gear to save space and for international standardization) and connecting computer equipment to the output of a UPS (larger UPSs often have C19 outlets as well.)

Power cord featuring a CEE 7/7 plug (European wall socket) at the left end, and an IEC C13 at the right end.

C15 and C16 connectors

Some electric kettles and similar hot household appliances use a cord with a C15 line socket, and a matching C16 inlet connector on the appliance. (This has led to the widely used slang of "kettle plug" and "jug plug" when referring to C15 and C16 connectors.) These are similar to the C13 and C14 combination but have a higher temperature rating, 120 degrees Celsius rather than 70 degrees Celsius, and a ridge (in the socket) or valley in the plug. In Britain the C15 and C16 connectors have replaced and made obsolete the appliance plug in most applications.

The C15 line socket will fit the C14 inlet, but the C13 will not fit the C16. That is, you can use an electric kettle cord to power a computer, but not a computer cord to power a kettle. The C16 socket has a plastic ridge opposite the earth pin - preventing C13s fitting but C15s have a groove to match. Many people do not notice this subtle distinction and refer to cords with both variants as "kettle leads" in the United Kingdom, and "kettle cords" or "jug plugs" in Australia. The official designation in Europe for the C15 and C16 connectors is 'hot condition' connectors.

C17 and C18 Connectors

Similar to C13 and C14 connectors. However the C17 and C18 do not have a third pin for earthing. A C18 inlet will accept a C13 line socket but a C14 inlet will not accept a C17 line socket.

IBM's Wheelwriter series of electronic typewriters are one common application. Three wire cords with C13 sockets - which are easier to find - are sometimes used in place of the two wire cords for replacement. In this case, the ground wire will not be connected

Another common application is on the power supplies of Xbox 360 games consoles, replacing the C15 and C16 connectors employed initially.

C19 and C20 Connectors

C19 and C20 connectors, with pins rated at 16 A, are used for some server room applications where higher currents are required. For instance, on high-power servers, UPSs, PDUs and similar datacenter equipment. They are similar to C13 and C14 connectors, but rectangular (without chamfered corners) and with the pins rotated so they are parallel to the long axis of the connector.

C7 and C8 Connectors

The C7 and C8 connectors, with two pins rated at 2.5 A, exist in both polarised and unpolarised versions.

The unpolarised C7 (commonly known as "Figure 8") connector is often used for small cassette recorders and battery/mains operated radios.

The polarised C8 is asymmetrical, with one end rounded similarly to the unpolarised version, and the other squarish. It is used for some full size AV equipment and laptop computer power supplies, video game consoles, and similar double-insulated appliances. Unpolarised C7 connectors can be used with appliances that require a polarized C8.

Other IEC appliance connectors

The unpolarised C1 is commomly used for shavers.

The 3-connector C5 (colloquially called "Mickey Mouse" (cross section looks like his silhouette) or "Clover Leaf") connector is seen on some laptop power supplies and portable projectors.

In each case, the matching inlet is designated by the even number one greater than the odd number assigned to the line socket, so a C1 fits a C2, and a C15A fits a C16A. Most are polarised (though of course being a worldwide standard they will frequently be connected to wall outlets that are unpolarised), the exceptions being the C1, some C7 and all C9 plugs. All voltage ratings are 250 VAC. All have maximum temperature ratings of 70 °C unless noted.

*C1 2-conductor 0.2 A (unpolarised)
*C3 2-conductor 2.5 A
*C5 3-conductor 2.5 A - often referred to as 'Mickey Mouse' or 'Clover Leaf'
*C7 2-conductor 2.5 A (polarised or unpolarised) - unpolarised connector often referred to as 'figure of eight' or 'shotgun'
*C9 2-conductor 6 A (unpolarised)
*C11 2-conductor 10 A
*C13 3-conductor 10 A
*C15 3-conductor 10 A (120 °C maximum temperature)
*C15A 3-conductor 10 A (155 °C maximum temperature)
*C17 2-conductor 10 A
*C19 3-conductor 16 A
*C21 3-conductor 16 A (155 °C maximum temperature)
*C23 2-conductor 16 A

Power Entry Modules

Some manufacturers have combined IEC Connectors with other associated power components. See Power entry module for details.

"There are some physical compatibilities not noted here."

References

* [http://webstore.iec.ch/webstore/webstore.nsf/searchview/?searchView=&SearchOrder=4&SearchWV=TRUE&SearchMax=1000&Submit=OK&Query=(%5BCommittee%5D=23G) search for other SC 23G publications]
* [http://webstore.iec.ch/webstore/webstore.nsf/artnum/038670 IEC 60320-1 Consol. Ed. 2.1]
* [http://webstore.iec.ch/webstore/webstore.nsf/artnum/026278 IEC 60320-2-1 Ed. 2.0]
* [http://webstore.iec.ch/webstore/webstore.nsf/artnum/023204 IEC 60320-2-2 Ed. 2.0]
* [http://webstore.iec.ch/webstore/webstore.nsf/artnum/033613 IEC 60320-2-3 Consol. Ed. 1.1]
* [http://webstore.iec.ch/webstore/webstore.nsf/artnum/033451 IEC 60320-2-3-am1 Ed. 1.0]
* [http://webstore.iec.ch/webstore/webstore.nsf/artnum/035019 IEC 60320-2-4 Ed. 1.0]
* [http://webstore.iec.ch/webstore/webstore.nsf/artnum/023182 IEC 60799 Ed. 2.0]
* [http://www.accesscomms.com.au/reference/IEC320.htm IEC-320 Appliance Connectors] (includes diagrams of all IEC connectors)
* [http://www.stayonline.com/reference-iec320.aspx International Standardized Appliance Connectors (IEC-60320) Reference Chart] ᾹIncludes diagrams of all connectors, their rated current, equipment class, and temperature rating.