IEC 61241-17-2005 pdf – Electrical apparatus for use in the presence of combustible dust – Part 17: Inspection and maintenance of electrical installations in hazardous areas (other than mines).
1 Scope This part of IEC 61241 is intended to be applied by users and covers factors directly related to the inspection and maintenance of electrical installations within hazardous areas only. It does not include conventional requirements for electrical installations, nor the testing and certification of electrical apparatus. This standard supplements the requirements laid down in IEC 60364-6-61. NOTE The text is based on IEC 60079-17. This standard assumes effective housekeeping based on a system of cleaning for the plant. The principles of this standard can also be followed when combustible fibres or flyings may cause a hazard. This standard is intended to be applied where there can be a risk due to the presence of explosive dust/air mixtures or combustible dust layers under normal atmospheric conditions. It does not apply to • underground mining areas, • areas where a risk can arise due to the presence of hybrid mixtures, • dusts of explosives that do not require atmospheric oxygen for combustion, or to • pyrophoric substances. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60079-14:2002, Electrical apparatus for explosive gas atmospheres – Part 14: Electrical installations in hazardous areas (other than mines) IEC 60364-6-61: Electrical installations of buildings – Part 6-61: Verification – Initial verification IEC 61241-4, Electrical apparatus for use in the presence of combustible dust – Part 4: Type of protection “pD” IEC 61241-10, Electrical apparatus for use in the presence of combustible dust – Part 10: Classification of areas where combustible dusts are or may be present
3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 explosive atmosphere mixture with air, under atmospheric conditions, of flammable substances in the form of gas, vapour, mist or dust, in which after ignition, combustion spreads throughout the unconsumed mixture 3.2 explosive dust atmosphere mixture with air, under atmospheric conditions, of flammable substances in the form of dust, fibres or flyings in which, after ignition, combustion spreads throughout the unconsumed mixture 3.3 hazardous area area in which an explosive atmosphere is present, or may be expected to be present, in quantities such as to require special precautions for the construction, installation and use of apparatus NOTE For the purposes of this standard, an area is a three-dimensional region or space. 3.4 non-hazardous area area in which an explosive atmosphere is not expected to be present in quantities such as to require special precautions for the construction, installation and use of apparatus 3.5 maintenance combination of any actions carried out to retain an item in, or restore it to, conditions in which it is able to meet the requirements of the relevant specification and perform its required functions 3.6 inspection action comprising careful scrutiny of an item carried out either without dismantling, or with the addition of partial dismantling as required, supplemented by means such as measurement, in order to arrive at a reliable conclusion as to the condition of an item 3.6.1 visual inspection inspection which identifies, without the use of access equipment or tools, those defects, such as missing bolts, which will be apparent to the eye
3.6.2 close inspection inspection which encompasses those aspects covered by a visual inspection and, in addition, identifies those defects, such as loose bolts, which will be apparent only by the use of access equipment, for example steps, (where necessary), and tools NOTE Close inspections do not normally require the enclosure to be opened, or the equipment to be de- energized. 3.6.3 detailed inspection inspection which encompasses those aspects covered by a close inspection and, in addition, identifies those defects, such as loose terminations, which will only be apparent by opening the enclosure, and/or using, where necessary, tools and test equipment 3.6.4 initial inspection inspection of all electrical apparatus, systems and installations before they are brought into service 3.6.5 periodic inspection inspection of all electrical apparatus, systems and installations carried out on a routine basis 3.6.6 sample inspection inspection of a proportion of the electrical apparatus, systems and installations 3.7 continuous supervision frequent attendance, inspection, service, care and maintenance of the electrical installation by skilled personnel who have experience in the specific installation and its environment in order to maintain the explosion protection features of the installation in satisfactory condition 3.8 skilled personnel people who meet the requirements for the qualification of personnel in accordance with 4.2 3.9 technical person with executive function person providing technical management of the skilled personnel, having adequate knowledge in the field of explosion protection, having familiarity with the local conditions, having familiarity with the installation and who has overall responsibility and control of the inspection systems for the electrical equipment within hazardous areas