1. Scope

1.1 This standard covers the essential requirements for distribution of power from an extra low voltage 48 V d.c. power source. Power sources include, but are not limited to, interconnected or stand-alone batteries, solar photovoltaic systems, other distributed renewable generation systems, or generators. All sources of SELV and PELV as defined in IEC 60364-4-41:2005 ‘Lowvoltage electrical installations - Part 4-41: Protection for safety - Protection against electric shock’ are applicable but with a nominal voltage of 48V.

1.2 This standard is also applicable to locations where electrical utility service is not available and power is derived from single or multiple renewable energy sources. Safety isolation transformer or Class II power converters shall be used, if the voltage at any point in the power conversion system exceeds 60V in the process of 48V generation for feeding into the distribution system.

1.3 This standard is applicable to dwelling units and commercial units either single or multiple, guest rooms or guest suites of hotels, motels or similar occupancies, mobile homes, and in-building applications in general. This code also covers essential requirements and precautions regarding wiring installations and equipment powered by d.c. sources for ensuring satisfactory and reliable service with the best possible energy efficiency. Installation includes all components involved in the supply of power from the source. Examples of Installation Wiring Components include distribution boxes, plugs and sockets, cables, power cords, etc.

1.4 Even though the power source is separated extra low voltage by definition, there are circumstances where safety needs to be addressed, especially during distribution. This standard also covers safety requirements for the installations.

2. REFERENCES

The following standards contain provisions which, through reference in this text, constitute provisions of this standard. At the time of publication of this standard, the edition indicated are valid. All standards are subject to revision and parties to agreement based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below:

732 :1989 Code of Practice for electrical wiring installations

302-1 : 2008 Safety of household and similar electrical appliances : Part 1 General Requirements

13252 (Part 1) : 2010 Information technology equipment - Safety : Part 1 General Requirements

13703 (Part 1) : 1993 LV Fuses for voltages not exceeding 1000 V a.c. or 1500 V d.c.: Part 1 General requirements

IEC 60038 : 2009 IEC standard voltages

IEC 60269-2: Low-voltage fuses - Part 2: 2013 Supplementary requirements for fuses for use by authorized persons (fuses mainly for industrial application) - Examples of standardized systems of fuses A to K

IEC 60364-1: 2005 - Part 1 : Low-voltage electrical installations Fundamental principles, assessment of general characteristics, definitions

IEC 60364-4-41: 2005 - Part 4-41:Low-voltage electrical installations Protection for safety - Protection against electric shock

IEC 60364-4-43:2008 - Part 4-43: Low-voltage electrical installations Protection for safety Protection against overcurrent

IEC 60364-4-44: 2008 - Part 4-44: Low-voltage electrical installations Protection for safety - Protection against voltage disturbances and electromagnetic disturbances

IEC 60364-4-53 : 2008 Part 5-53 : Electrical installations of buildings - Selection and erection of electrical equipment - Isolation, switching and control

IEC 60445 : 2017 Basic and safety principles for manmachine interface, marking and identification - Identification of equipment terminals, conductor terminations and conductors

IEC 61140 : 2016 Protection against electric shock - Common aspects for installation and equipment

IEC 61439-3: 2012 Low-voltage switchgear and controlgear assemblies - Part 3: Distribution boards intended to be operated by ordinary persons (DBO)

IEC 61643-21: 2000 Low voltage surge protective devices - Part 21: Surge protective devices connected to telecommunications and signalling networks - Performance requirements and testing methods

IEC TS 62257-2 : 2015 Recommendations for renewable energy and hybrid systems for rural electrification - Part 2: From requirements to a range of electrification systems

IEC TS 62257-7-1 : 2010 Recommendations for small renewable energy and hybrid systems for rural electrification - Part 7-1:Generators - Photovoltaic generators

IEC TS 62257- 8-1 : 2007 Recommendations for small renewable energy and hybrid systems for rural electrification - Part 8-1: Selection of batteries and battery management systems for stand-alone electrification systems - Specific case of automotive flooded lead-acid batteries available in developing countries