Boxes and enclosures for electrical accessories for household and similar fixed electrical installations – Part 24: Particular requirements for enclosures for housing protective devices and other power dissipating electrical equipment
|Publication Date:||1 March 2011|
|ICS Code (Conduits for electrical purposes):||29.120.10|
This part of IEC 60670 applies to enclosures and parts of them for housing protective devices and other power dissipating electrical equipment intended to be used with a rated voltage not exceeding 400 V and a total incoming load current not exceeding 125 A for household and similar fixed electrical installations.
These enclosures are intended to be installed where unskilled persons have access. They are intended to be integrated with electrical equipment on site by skilled persons (installers).
They are intended to be installed where the prospective short circuit current does not exceed 10 kA unless they are protected by current limiting protective devices with a cut-off current not exceeding 17 kA.
Enclosures complying with this standard are suitable for use, after installation, at ambient temperature not normally exceeding 25 °C, but occasionally reaching 35 °C over 24 h, max. 40 °C and min. -5 °C.
An enclosure which is an integral part of an electrical accessory and provides protection against external influences (e.g. mechanical impacts, ingress of solid objects or of water), is covered by the relevant standard for such an accessory.
This standard does not apply to a low-voltage switchgear and controlgear assembly (ASSEMBLY) as defined in the IEC 60439 or IEC 61439 series of standards nor to a main entrance panel which may or may not be part of the distribution board.
NOTE 1 A main entrance panel is a set composed by a panel or an enclosure equipped with a meter and/or the main incoming device. Main entrance panels comply with their appropriate standards or the requirements of the local supplier if any.
NOTE 2 In the following country this standard cannot be used in installations with a 230 V single-phase supply rated up to 100 A that is under the control of ordinary persons. Integration of mechanical and electrical devices into an enclosure must be verified by compliance with IEC 60439-3 [British standard EN 60439-3]: UK.
NOTE 3 In the following country this standard can only be used for GP enclosures with the instructions according to Annex A. For the other types of enclosures the integration of mechanical and electrical devices into an enclosure is verified by compliance with DS EN 60439-3: DK.