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ADDENDUM FOR "EX SAFETY" ASPECTS AND "IP" PROTECTION (EUROPE)
b) Certificate ATEX II 1/2 GD T50
°
C, EEx ia IIC T6 (-40
°
C
≤
Ta
≤
+40
°
C)
respectively, GD T95
°
C, EEx ia IIC T4 (-40
°
C
≤
Ta
≤
+85
°
C)
ZELM certificate number ZELM 02 ATEX 0081
Note: this ATEX Category depends on the application (see below) and also on the intrinsic safety level of the transmitter
supply (associated apparatus) which can sometimes suitably be [ib] instead of [ia]. As it is well known, the level of an
intrinsic safety system is determined by the lowest level of the various apparatus used, i.e., in the case of [ib] supply, the
system takes over this level of protection.
The meaning of ATEX code is as follows:
II :
Group for surface areas (not mines)
1/2 :
Category - It means that only a part of the transmitter complies with category 1 and a
second part complies with category 2 (see next application sketch)
G :
Gas (dangerous media)
D :
Dust (dangerous media)
T50
°
C:
Maximum surface temperature of the transmitter enclosure with a Ta (ambient temperature)
+40
°
C for Dust (not Gas) with a dust layer up to 50 mm depth.
T95
°
C:
As before for Dust for a Ta +85
°
C
(Note: the number close to the CE marking of the transmitter safety label identifies the Notified Body which has responsibility
for the surveillance of the production)
The other marking refers to the protection type used according to relevant EN standards:
EEx ia :
Intrinsic safety, protection level “a”
IIC :
Gas group
T6 :
Temperature class of the transmitter (which corresponds to 85
°
C max)
with a Ta (ambient temperature) +40
°
C
T4 :
Temperature class of the transmitter (which corresponds to 135
°
C max)
with a Ta (ambient temperature) +85
°
C
About the applications, this transmitter can be used in Zone “0” (Gas) classified areas (continuous hazard) with its “process
part” only, whereas the remaining part of the transmitter, i.e. its enclosure, can be used in Zone 1 (Gas), only (see sketch
below). Reason of this is the process part of the transmitter (normally called primary transducer) that provides inside separation
elements to seal off the electrical sensor from the continuously hazardous process, according to the EN50284 and EN50018.
About Dust application, the transmitter is suitable for "Zone 21" according to the EN 50281 as it is shown on the relevant part of
the sketch:
APPLICATION FOR PRESSURE TRANSMITTER EEx ia CATEGORY 1/2 GD
+
Zone "0"
dangerous
medium
(process)
Tank
2600T Tx
category 1/2 G
EEx ia
Zone 0 / Zone 1
Separation elements
Zone "1"
Primary transducer
(Note: see the
certificate for
exception )
Zone "20"
dangerous
medium
(process)
Silo
2600T Tx
category 1/2D
IP6x
(EEx ia)
Zone "21"
Application with Gas
Application with Dust
+
Note: the transmitter can be connected to
either [ib] or [ia] supply (associated apparatus)
Note: the protection is mainly assured by the "IP
degree" associated to the low power from the supply.
This can either be [ib] or [ia]
Summary of Contents for 264B
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