WFP RMMI Facilities Management Branch Regulatory framework for WFP electrical installations. Electrical Standards around the world

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1 Regulatory framework for WFP electrical installations Electrical Standards around the world

2 Fundamental characteristics of power supply There are two main standards for single phase voltage and frequency: - North American standard of Volts(three-phase V) at a frequency of 60 Hz; - European standard of volts(three-phase V) at a frequency of 50 Hz. However, different combinations of voltage and frequency can be found throughout the world. -Voltage,orTension,hasadirecteffectonthecurrentflowingintowires. e.g.aloadin110vsinglephaserequires twicethecurrentrequiredbythesameloadin220vsingle phase. -Frequencydoesnotaffectthecurrentrequiredbyaload,butithasaneffectontheperformanceof some appliances e.g. electrical engines in A/C units can be damaged by a different frequency

3 Distribution of Power supply characteristics in the world

4 National / International standards and codes Electrical codes are intended to protect people and property from electrical shock and fire hazards, while ensuring reliability of systems. Codes are usually produced by a technical standards-setting organization (at a National or international level). Public authorities may establish regulations by adopting a code and advising or enforcing its application(with or without local amendment). Most common codes: - NATIONAL ELECTRIC CODE (NEC) published in the United States by the National Fire Protection Association under thenameofnfpa70.nfpa702011editioniscompliantwithiec60364safetyrequirements. - IEC Electrical Installations for buildings published by the International Electro-Technical Commission. All European national codes are harmonized with IEC standards through CENELEC (European Committee for Electrotechnical Standardization). - BS7671 Requirements for Electrical Installations published in Great Britain by the Institution of Engineering and Technology. Harmonized with IEC ISO standards - published by the International Organization for Standards(cooperates with IEC). Wire Sizes The international standard wire sizes are given in the IEC standard. In North America, the American Wire Gauge standard for wire sizes is used.

5 Electrical codes and standardization

6 International Electro-Technical Commission members and affiliates

7 Practical difference: color codes for wires IEC identifies 14 types of sockets

8 Practical difference: sockets and plugs IEC Technical Report identifies 14 maintypes of plugs and sockets (A to N) used throughout the world provides an interactive map showing distribution of the different types Although some of the plugs might fit into different sockets, physical characteristics are not the only factor to consider. The Ampere rating is extremely important, as forcing a plug into a socket with a different Ampere rating might cause overheating and even result in a fire. Circuit breakers should be coordinated with the ampere rating of supplied sockets.

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10 How to operate in a multinational context Purpose of the study: to ensure consistency as to the level of safety, reliability and efficiency throughout WFP network of facilities. To be effective, a code for electrical installations must be: - suitable for the existing electrical infrastructure; - suitable for the electrical safety system employed in a country; - capable of being uniformly interpreted, applied, and enforced. It must also ensure compatibility with standards applicable to products whose installation, operation and maintenance is intended to be governed by the code. In an international context the selection of a single standard and/or code would not satisfy these requirements everywhere. Flexibility is the key.

11 WFP Standard: general objectives for electrical installations Design, erection, operationand maintenanceof electrical installations in WFP should pursue the following objectives, hereby listed by priority level: SAFETY:protectionof persons, livestockand propertyin accordancewith requirements and principles of IEC ; RELIABILITY: functionality, dependability and effectiveness of the electrical installationfor the intendeduse, in accordancewith basicrequirementsand principlesof IEC ; EFFICIENCY:the electricalinstallationshouldachievethe objectivesof safetyand reliability optimizingenergyconsumption, containingoverallfootprintand expenses, takingintoaccount the wholelifecycleof the installationfrom design to decommissioning.

12 WFP Standard: structure and key factors NB the selection of the applicable code will also take account of the existing systems and relevant standards

13 WFP Standard: structure and contents

14 Bibliography STANDARDS AND SPECIFICATIONS - IEC 60364:2005 International Standard: Low-voltage electrical installations - NFPA Edition: National Electric Code - NFPA 70E 2012 Edition: Standard for Electrical Safety in the Workplace - ISO/IEC Guide 21-1:2005 Regional or national adoption of International Standards and other International Deliverables - BS 7671: Edition: Wiring regulations - IEC TS 62257:2005 Technical Specification: Recommendations for small renewable energy and hybrid systems for rural electrification LITERATURE - Electrical installation requirements: a global perspective National Electrical Manufacturers Association (USA) By Underwriters Laboratories Inc. Principal Investigator Paul Duks April ISO/IEC Using and referencing standards for technical regulations September WFP Climate Neutral Emission Reduction Strategy WFP Climate Neutral Team - International Electrical Standards and Regulations Brochure by Legrand 2012