WAGO 750-306 Technical Description page 143

6.3.5 Types of Ignition Protection
Ignition protection defines the special measures to be taken for electrical
components in order to prevent the ignition of surrounding explosive at-
mospheres. For this reason a differentiation is made between the following
types of ignition protection:
Identifi-
cation
EEx o
EEx p
EEx q
EEx d
EEx e
EEx m
EEx i
EEx n
Ignition protection "n" describes exclusively the use of explosion protected
electrical components in zone 2. This zone encompasses areas where ex-
plosive atmospheres can only be expected to occur rarely or short-term. It
represents the transition between the area of zone 1, which requires an ex-
plosion protection and safe area in which for instance welding is allowed at
any time.
Regulations covering these electrical components are being prepared on a
world-wide scale. The standard EN 50 021 allows electrical component
manufacturers to obtain certificates from the corresponding authorities for
instance KEMA in the Netherlands or the PTB in Germany, certifying that
the tested components meet the above mentioned standards draft.
Type "n" ignition protection additionally requires electrical components to
be marked with the following extended identification:
• A – non spark generating (function modules without relay /without
• AC – spark generating, contacts protected by seals (function modules
• L – limited energy (function modules with switch)
Further information
For more detailed information please refer to the national and/or international
standards, directives and regulations!
WAGO-I/O-SYSTEM 750
DeviceNet
CENELEC Standard IEC Stan-
EN 50 015
EN 50 016
EN 50 017
EN 50 018
EN 50 019
EN 50 028
EN 50 020 (unit)
EN 50 039 (system)
EN 50 021
switches)
with relays / without switches)
Application in Explosive Environments • 143
Classification Meeting CENELEC and IEC
Explanation
dard
IEC 79-6 Oil encapsulation
IEC 79-2 Overpressure encap-
sulation
IEC 79-5 Sand encapsulation
IEC 79-1 Pressure resistant
encapsulation
IEC 79-7 Increased safety
IEC 79-18 Cast encapsulation
IEC 79-11 Intrinsic safety
IEC 79-15 Electrical components
for zone 2 (see below)
Application
Zone 1 + 2
Zone 1 + 2
Zone 1 + 2
Zone 1 + 2
Zone 1 + 2
Zone 1 + 2
Zone 0 + 1 + 2
Zone 2