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3.2 Intrinsic safe execution Ex ia
Ambient temperatures for intrinsic safety series:
Execution
Min. / Max. permissible ambient
temperature
Temperature class
Enclosure with wire
terminals (LS)
- 60°C to +80°C
T6
To avoid additional temperature increase, the devices should not be exposed to direct exposure to sunlight when in
operation!
When process temperatures for Ex ia are elevated, see below maximum temperature reachable on LS
stem/slide bar
3.2.1 Labeling
Ex marking according to
2014/34/EU
Ex marking
according to EN 60079-0
II
1G
Ex ia
IIC
IIB
T6
Ga
X
CE marking
Marking for explosion protection
II
Group II equipment is intended for use in places
with explosive gas atmospheres, excluding mine
gas and/or dust from hazardous mining
operations.
1G
Equipment group for gases and vapors in which an
explosive atmosphere may occur continuously during
normal operation.
Ex ia
Marking according to the equipment protection level for electrical
equipment in potentially explosive atmospheres
(intrinsic safety)
IIB
Suitable for gas atmosphere IIB
IIC
Suitable for gas atmosphere IIC
T6
Maximum surface temperatures which are mainly dependent on the operating conditions
Ga
Equipment for explosive gas atmospheres, having a “very high” level of protection, which is not a
source of ignition in normal operations, during expected malfunctions or during rare
malfunctions.
X
Special conditions of use must be observed
Model
EPL
Ambient
Temperature
MAX. Process
Temperature
Temperature
Class
Level Switch (LS)
ia
-60°C +80°C
80°C
T6
ia
-60°C +70°C
150°C
T6
