ATEX certified encoders Compliance with the ATEX ("Atmosphères explosibles") European Directive is a legal requirement in all European Union Member States for any equipment intended for use in potentially explosive atmospheres. Equipment and protective systems for use in hazardous areas must comply with the statements of the ATEX Directive 2014/34/EU, commonly referred to as the new ATEX "product" directive, which is applicable from 20 April 2016 and replaces the previous Directive 94/9/EC.
Lika Electronic has developed a comprehensive range of ATEX certified encoders: XC77 series, XAC77 series and XAC80 series. They are designed to cover a wide variety of critical applications in hazardous and harsh areas “in which explosive atmospheres caused by gases, vapours, mists or air/dust mixtures are likely to occur occasionally” (category 2 encoders) and “in which explosive atmospheres caused by gases, vapours, mists, or air/dust mixtures are unlikely to occur or, if they do occur, are likely to do so only infrequently and for a short period only” (category 3 encoders). Category 2 encoders suitable for zones 1, 2, 21 and 22 XC77 and XAC77 series ATEX certified encoders are “high protection” category 2 compliant encoders: they provide an airtight, explosion-proof and flameproof enclosure and high ignition protection level against both gas and dust explosive atmospheres and are intended for use in Zones 1, 2, 21 and 22 and in the temperature class T6 (T85°C). They come in both incremental (XC77 series) and absolute (XAC77 series) versions and the most complete range of communication interfaces. Incremental versions provide NPN, Push-Pull, Line Driver and Universal level output signals. Absolute versions support a variety of electrical, fieldbus and Ethernet interfaces: SSI, BiSS, bit parallel, analogue, Profibus-DP, CANopen DS406, DeviceNet, Profinet, POWERLINK, EtherCAT and Modbus TCP. They bear the following ATEX marking, it is described below:
II2 GD, Ex d IIC T6 Gb, Ex tb IIIC T85°C Db, IP65 II2 GD, Ex d IIB T6 Gb, Ex tb IIIC T85°C Db, IP65
Category 3 encoders suitable for zones 2, 22 XAC80 series ATEX certified encoders are the fieldbus and Ethernet absolute encoders designed to provide “normal protection” in potentially explosive atmospheres (category 3) and are allowed to be used in Zones 2 and 22 and in the temperature class T5 (T100°C). They are offered in absolute version and the most complete range of communication interfaces: SSI, BiSS, bit parallel, analogue, Profibus-DP, CANopen DS406, DeviceNet, Profinet, POWERLINK, EtherCAT and Modbus TCP. They bear the following ATEX marking, it is described here below: II3 GD, Ex nA IIB T5 Gc, Ex tc IIIC T100° Dc, IP65
XC77, XAC77 ATEX Category 2 Zones 1, 2, 21, 22
II2 GD, Ex d IIC T6 Gb, Ex tb IIIC T85°C Db, IP65 II2 GD, Ex d IIB T6 Gb, Ex tb IIIC T85°C Db, IP65
XAC80 ATEX Category 3 Zones 2, 22
II3 GD, Ex nA IIB T5 Gc, Ex tc IIIC T100° Dc, IP65
Understanding the ATEX marking Gases
A
Dusts
B
C
D
E
F
G
H
E
F
G
H
I
II
2
GD
Ex d
IIC
T6
Gb
Ex tb
IIIC
T85°C
Db
IP65
A
Mark for ATEX certified electrical equipment for explosive atmospheres
B Equipment group
European standards divide equipment into two main groups, Group 1 (mines) and Group 2 (normal surface industries), based on the type of hazardous location. II, Group 2 covers the gases and vapours that are present in normal surface industries. This group is further subdivided into three categories in order to more clearly define the necessary protection levels required according to risk levels.
C Equipment category
Subdivision of the previous listed groups. 2, Category 2 is considered “high protection” and refers to non mining equipment in above ground or surface locations for “use in areas in which explosive atmospheres caused by gases, vapours, mists or air/dust mixtures are likely to occur occasionally”. 3, Category 3 is considered “normal protection” and refers to non mining equipment in above ground or surface locations for “use in areas in which explosive atmospheres caused by gases, vapours, mists, or air/dust mixtures are unlikely to occur or, if they do occur, are likely to do so only infrequently and for a short period only".
D Environment
G: for use with gases, vapours, mists D: for use with air/dust mixtures
E Explosion protection and type of protection
Ex d: flameproof, contain the explosion, quench the flame. "Ex d" denotes the ability of a device to contain any ignition within itself and prevent the escape of any ignition from the enclosure. Sparks, flame, ignited materials could exist or occur within the enclosure but are not permitted to escape and contact the atmosphere outside of the enclosure. Ex nA: no arcs, sparks or hot surfaces Ex tb: standard protection for dust, rugged tight enclosure, for zone 21 Ex tc: standard protection for dust, rugged tight enclosure, for zone 22
F Gas / Dust group
Group II locations offer a wide range of potential gases/vapours that need to be protected against, and as a result, the danger of gases is covered by subdivisions, with IIA being the least dangerous, to subdivision IIC being the most dangerous. IIB: ethylene IIC: acetylene and hydrogen IIIC: conductive dust
G Temperature class
T5: max. surface temperature 100°C (gas environment) T6: max. surface temperature 85°C (gas environment) T100°C: max. surface temperature 100°C (dust environment) T85°C: max. surface temperature 85°C (dust environment)
H Equipment protection level (EPL)
Gb: high level of ignition protection against gas and vapour Gc: normal level of ignition protection against gas and vapour Db: high level of ignition protection against dust Dc: normal level of ignition protection against dust
I International protection code (IP code)
IP65: 6 = totally protected against dust; 5 = protected against jets of water from any directions
Zones Gases/Vapours ZONE 1: this zone refers to an area where the atmosphere is likely to pose an explosion or fire hazard during normal operations. ZONE 2: this zone refers to an area where an explosive atmosphere is not and should not normally be present during normal operations, and should it appear, will only be present for a short period of time. Combustible Dusts ZONE 21: this zone refers to an area where a cloud of combustible dust in the air is likely to pose an explosion or fire hazard during normal operations. ZONE 22: this zone refers to an area where a cloud of combustible dust in the air is not and should not normally be present during normal operations, and should it appear, will only be present for a short period of time.
Meet Lika at the OFFSHORE ENERGY 2016 exhibition! Since 2008 Offshore Energy Exhibition & Conference (OEEC) is the annual event focused on the complete offshore energy industry, from oil & gas to wind and marine energy. It will be held on 25 and 26 October 2016 in the Europe Complex of the Amsterdam RAI, Amsterdam, the Netherlands. Our experts will be on hand at booth 1.132B inside the Italy pavilion to answer all the questions about the measuring and control needs you may experience in your offshore applications. We are looking forward to meeting you at OEEC!
Offshore Energy 2016 Exhibition & Conference http://offshore-energy.biz/ 25 & 26 October 2016 Europe Complex at Amsterdam RAI https://goo.gl/maps/qnciuZcLQ862 Amsterdam, the Netherlands Opening hours 9:30 am – 6:00 pm CET Lika Electronic's Booth 1.132B