European standards for plugs and sockets

In 2012, the restructuring and revision of the safety requirements for low-voltage switchgear was finalised with publication of the standard, IEC 61439-1:2012. The preceding standard, IEC 60439-1 will be replaced by IEC 61439-1:2012. The former Standard IEC 60349 is valid until Sept. 2014. After this specified date, the use of IEC 61439 is mandatory (for all new designed switchgear and control gear assemblies) the planning  and documentation must be executed in accordance with IEC 61439-1:2012 and its parts.

The purpose of this standard is the harmonisation of most of the general regulations and requirements for lowvoltage switchgear and control gear assemblies to achieve uniform requirements and verifications for switchgear and control assemblies and to avoid the necessity of verifications in accordance with other standards. All requirements of the different switchgear and control gear assemblies have been combined in this fundamental standard, together with topics of broad interest and application, e.g heating, insulation properties, etc.

Two main standards will be required for each design of a low-voltage switchgear and control gear assembly:

• The basic standard that is referenced as "Part 1" in the specific standards;
• The applicable parts 2 to 7 of the switchgear and control gear assembly standard that deals with the particularities of the application.

The IEC 61439 consists of the following parts:

Requirements in this standard, which are object of an agreement between manufacturer of the switchgear and control gear assemblies and user, are summarised at the bottom. This listing facilitates provision of information concerning basic conditions and supplemental user definitions.

Additionally to the type verification, the producer has to provide an article proof which guarantees a correct set-up acc. to the norm, excludes material failures and the compliance with electrical safety requirements.

Original manufacturer

Organisation / enterprise that executed the original design and the associated verifications in accordance with the standard.

Manufacturer of the switchgear and control gear assembly

Organisation that completes a device and assembles it into a functional unit. The manufacturer is responsible for piece verification and thus for the product (Declaration of Conformity).

Significance for MENNEKES products:
For pre-wired devices MENNEKES is simultaneously the original manufacturer and the manufacturer. The responsibility and provision of verifications rest with us. We cannot declare partially wired devices that we manufacture as standard compliant. In this case the „finishing entity“ becomes the manufacturer and must declare conformity. It is required to forward information to this organisation so that the device ultimately can get a „eclaration of Conformity“.

The max. ambient temperature is +40 °C.
The average value of the ambient temperature over a period of 24 hours must not be higher than +35 °C.

The verification of heating can be provided through various methods. Through testing of the switchgear and control gear combination, or through derivation of a known reference, and through an expert assessment, e.g in accordance with applicable design rules. Regardless of the method that is selected to determine the heat and thus the maximum current load of the combination, compliance with the appropriate temperature limit values must be ensured.

The switchgear and control gear assembly and its electrical circuits must be capable of bearing their rated currents under defined conditions and the rated values of the components, their suitability and application must be taken into account, without exceeding limit values specified in IEC 61439-1 Table 6, Part 1. The limit temperatures in table 6 apply for the average ambient temperature of +35 °C.
▶ The limit temperatures of the installed equipment must be taken into account!

A device/component may only be replaced through a similar, identically constructed device a of a series other than the series used in the verification, if the power loss, and thus the heating of the connections is less than or equal to that of the device that is being replaced.

The requirement of EN IEC 61439-X is, that all electric circuits must be individually capable to carry their rated current, without exceeding temperature limit values in the process. If additional power circuits are added, a rated load factor can be set.

Standard definition InA

The rated current of the switchgear and control gear assembly, InA, is the total current that the main busbar can distribute in the respective installation of the assembly, without exceeding the temperature limit values mentioned in IEC 61439-1 section 9.2!

The current, InA, is considered to be the maximum current that the assembly can distribute via its outgoing circuits at 100 % continuous duty (CD).

Standard definition Inc

The rated current of an electric circuit is the value of the current that can be carried by this electric circuit under standard operating conditions when it is operated alone. The assembly must be capable of carrying this current without exceding the max. temperature limits of the individual components specified in IEC 61439-1 section 9.2.

Standard definition – rated diversity factor RDF

The RDF is the specified percentage value of the rated current with which the (individual) outgoing circuits Inc of a switchgear and control gear assembly can be continuously and simultaneously be used with due consideration of the opposing thermal influences. In this process the InA must not be exceeded.

This table provides guide values, if in doubt the manufacturer‘s specification always applies.

The information below represents specified standard values for MENNEKES catalogue assemblies. If there are deviations from this standard or in the case of special project planning, appropriate coordination must take place beforehand between user and manufacturer. These agreements must be arranged between MENNEKES and the user / customer during the quotation phase (prior to production and prior to sale).

The table below is a „blank“ that is applicable for approximately 98 % of the MENNEKES devices. Special project planning is not covered by the specifications, and must be separately disclosed by the user prior to project planning. In these special cases, it is required that additional details be considered with the aid of the standards cited and their product sub-standards.

* MENNEKES designs the size of the Neutral conductor accordingly to the max. allowed current for the phases. For special operating conditions (see IEC 61439, section 7.2 and IEC 61439-1 supplement 1, section 13.5) which relate to the ratio of neutral conductor to outer conductor (alternating current consumption with very low and different cosφ or excessive harmonics in the supply voltage or load current) can lead to a different size relation between neutral conductor to external conductor. This must be announced by the user.