Ex Survey According To Directive 94/9/Ec (Atex) - Siemens SITRANS F series Operating Instructions Manual

SITRANS F C MASSFLO 
2.3 Ex survey according
to Directive 94/9/EC
(ATEX)
6
2. Installation
Instrument groups
Applies to instruments used in underground mining
operations, as well as their above ground operations,
I
which can be endangered by mine gas and/or
flammable dusts.
Applies to instruments used in the remaining areas
II which can be endangered by a potentially explosive
atmosphere.
Instrument category
Definition
Instruments of this category are for use in areas
where ignitable atmospheres caused, by a mixture
1G
1D
of air and gasses, vapours or mists or by dust/
(0)
(20)
air mixtures, can exist all of the time or for long
periods of time or else frequently.
Instruments of this category are for use in areas
where ignitable atmospheres caused, by a mixture
2G
2D
(1) of air and gasses, vapours or mists or by dust/air
(21)
mixtures, can exist some of the time.
Instruments of this category are for use in areas
where ignitable atmospheres caused, by a mixture
of air and gasses, vapours or mists or by dust/air
3G
3D
(2) mixtures, are not likely to exist. However, if they
(22)
do occur then in all probability, only seldom or for
short periods of time.
(The figures in brackets refer to IEC)
Explosion protected electrial equipment = Ex
Ex protection labelling in square brackets refers to "Associated electrical equipment"
Type of protection
o Oil encapsulated
p Pressurized apparatus
q Powder filling
d Flameproof enclosure
e Increased safety
Explosion groups
Gases and vapours
(examples)
• Ammonia
• Acetone, aircraft fuel, benzine,
crude oil, diesel oil, ethane, ethanoic
acid, ether, gasolines, heating oil,
hexane, methane, propane
• Ethylene, isoprene, town gas
• Acetylene, carbon disulphide,
hydrogen
Ignition temperature
Maximum surface temperature
450°C
300°C
200°C
135°C
100°C
A5E02944883-AA
as an example
i Intrinsic safety (ia, ib)
n Non-incentive equipment
m Encapsulation
s Special protection
Minimum
ignition
energy [mJ]
-
0.18
0.06
0.02
EN / IEC
842°F T1
572°F T2
392°F T3
275°F T4
212°F T5
: II 2G Ex ia IIC T5
EN/
IEC
IIA
IIA
IIB
IIC