Flameproof Motors - Elec.ru

1. Technical Information1.1. Explosive AtmospheresA potentially explosive atmosphere is composed by air with mixturesof gases, vapours, mists or dusts, which might be ignited undercertain operating conditions.Equipment and protective systems intended for use in potentiallyexplosive atmospheres cover a quite large range of products,including equipment used on fixed offshore platforms, inpetrochemical plants, mines, flour mills and other areas where apotentially explosive atmosphere may arise.WEG has a long experience in the design and manufacturing ofmotors which fully comply the ATEX Directive 94/9/EC and theIECEx Scheme for Equipment Certification Program.WEG motors are manufactured to meet special applicationrequirements and severe duties in Hazardous Areas.www.weg.netof accidents, which all show that improved risk (health andsafety) management can substantially increase company profits.This latter being particularly true where potential explosions areconcerned.The Directive 1999/92/EC classifies the environment into zonesand outlines which category of equipment can be used in eachzone.This Directive concentrates on the duties of the End User whoseresponsibilities are mainly:The assessment of risksPreparation of an Explosion Protection DocumentThe provision of suitable warning signs for areas whereexplosive atmospheres may occur.The safety of an installation in a Hazardous Area is the result of cooperationbetween the equipment manufacturer, the installer and theend user.The ATEX Directives define Equipment Category, Zone and Groupas follows:1.2. Standards and Classification ofExplosive Atmospheres:1.2.1. ATEX DirectivesThe ATEX Directives were adopted by the European Union (UE) tosimplify the free trade between the member states by aligning thetechnical and legal requirements for products intended for use inpotentially explosive atmospheres.There are two main Directives, sharing the responsibilities betweenthe Manufacturer and the End User:The ATEX Manufacturers Directive 94/9/EC, also known asATEX 95, places the responsibilities on the manufacturers: Itspecifies the Essential Health and Safety Requirements thatmust be met by the equipment intended to be used in potentiallyexplosive atmospheres.In order to meet the ATEX Directive, products must complywith the Essential Requirements of this Directive and follow aConformity Assessment Procedure.This assessment procedure involves obtaining the EC TypeExamination certificate for products (requires the involvement ofa Notified Body except for category 3 products), the ProductionQuality Assurance (assessed by a Notified Body that issuesthe QAN – Quality Assessment Notification according with EN13980 and periodically makes the audits) and an internal controlof production (where the manufacturer carries out the necessarywork to guarantee that the products are in compliance with theATEX Directive).The ATEX product markings can be easily recognized by thesymbol that indicates the explosion protection and by themark that certifies the conformity with this Directive.The need to reduce the incidence of explosions and flashfires at work is prompted by both humanitarian and economicconsiderations and has led to the adoption by the EuropeanParliament and the Council of the ATEX Directive 1999/92/EC, also known as ATEX 137, that lays down the minimumrequirements for improving the safety and health protection ofworkers potentially at risk from explosive atmospheres.The humanitarian considerations are obvious: explosions andfires can cause hideous injuries and deaths. The economicconsiderations are contained in every study into the true costsEquipment intended for use in minesGroup IRemain functional,even in the event of Intended to beLevel of safetyrare incidents related de-energized in theto equipment with an event of an explosiveexplosive atmosphere atmospherepresent.Equipment category M1 M2Table 1.01 - Group I equipmentEquipment intended for use in surface industryGroup IIZone 0 20 1 21 2 22Type of explosiveatmosphereGGasDDustGGasDDustGGasDDustLikelihood ofInfrequently andOccasionallyan explosive Always presentonly for a shortpresentatmosphereperiodEquipmentcategory1 2 3Table 1.02 - Group II equipment1.2.2. IECEx SchemeThe objective of the IECEx System is to facilitate international tradein equipment and services for use in explosive atmospheres, whilemaintaining the required level of safety. IECEx System is acceptedin many countries and aims to be the world approval systemfor electrical equipment to be installed in potentially explosiveatmospheres.The IECEx System is based on the use of International Standards,such as IEC Standards. These Standards are dedicated to thehighly specialised fields associated with the use of equipment,named Ex equipment and installations in areas where a potential riskof fire or explosion may exist.The administration of the IECEx System is governed by the IECExRules which are available for free in the IECEx website (http://www.iecex.com). Operational Documents supplement the Rules ofProcedure and are for use within the IECEx System and Schemes.The IECEx International Certification System comprises four differentSchemes:Flameproof Motors | 7