IEC 60320 connector is a set of standards from the International Electrotechnical Commission specifying non-locking electrical power couplers for the connection of power supply cords to electrical appliance up to 250 V. Couplers described under these standards have standardized current and temperature ratings. Use of standard inlets and country-specific cord sets allows manufacturers to produce the same appliance for many markets, where only the cord set has to be changed for a particular market. Compatible connectors are also made for equipment that requires power outlets for interconnection.
The standards define the mechanical, electrical and thermal requirements and safety goals of power couplers. The standard scope is limited to appliance couplers rated at 250 VAC, up to 16A (20A 125/250 VAC UL respectively). Further sub-parts of IEC 60320 focus on special topics such as protection ratings and appliance specific requirements.
The shape and dimensions of appliance inlets and connectors are coordinated, so that a connector with lower current rating, temperature rating, or polarization cannot be inserted into an appliance inlet that requires higher ratings. It is impossible, for instance, to connect a Protection Class II connector, which has no earthing, to a Protection Class I appliance inlet which requires an earth. The opposite (i.e., connecting a Protection Class I connector to a Protection Class II appliance inlet) is possible because it creates no safety hazard for the appliance user. The same applies to the nominal current and the pin temperature. This coding plays a significant role in the safe operation of appliances and the protection against improper use.
Pin temperature is measured where the pin projects from the engagement surface. The maximum permitted pin temperatures, are 70 °C, 120 °C, and 155 °C, respectively. The pin temperature is determined by the design of the appliance, and its interior temperature, rather than by its ambient temperature. Typical applications with increased pin temperatures include appliances with heating coils such as ovens or electric grills. It is generally possible to use a connector with a higher rated temperature with a lower rated appliance inlet, but the keying feature of the inlet prevents use of a connector with a lower temperature rating.
Selection of a coupler depends in part on the IEC appliance classes. Class I appliances must have their chassis connected to electrical earth and require a coupler with earthing. Class II double insulated electrical appliances do not require a safety connection to electrical earth and can use a coupler with only two circuit conductors.
In addition to the limiting values described, the standards define further general criteria such as withdrawal forces, testing procedures, the minimum number of insertion cycles, and the number of flexings of cords. IEC 60320-1 codes the various plug outlines using a combination of letters and numbers, e.g., "C14", while IEC 60320-2-2 uses a single letter, e.g., "F".
In addition to the connections within the standards, as mentioned, there are possible combinations between IEC 60320-1 and IEC 60320-2-2. Fitted with a flexible cord, the components become interconnection cords to be used for connecting appliances or for extending other interconnection cords or power supply cords.