Special Hazards; Labelling / Safety Marks - WIKA 632.51 Betriebsanleitung

2. Safety
Explosive dust atmosphere
For dusts, the procedure specified in ISO/IEC 80079-20-2 for determining the ignition
temperature has to be applied. The ignition temperature is determined separately for dust
clouds and dust layers, respectively. For dust layers, the ignition temperature depends on the
dust layer thickness per IEC/EN 60079-14.
Ignition temperature of
dust
EN
Dust cloud: T
cloud
Dust layer: T
layer
The medium temperature must not exceed the lowest determined value for the maximum
permissible surface temperature, even in case of a malfunction.
Explosive atmosphere consisting of hybrid mixtures
The instruments must not be used in areas in which an atmosphere consisting of explosive
hybrid mixtures (dusts mixed with gases) can occur.

2.5 Special hazards

WARNING!
For hazardous media such as oxygen, acetylene, flammable or toxic gases or
liquids, and refrigeration plants, compressors, etc., in addition to all stand-
ard regulations, the appropriate existing codes or regulations must also be
followed.
WARNING!
Residual media in dismounted instruments can result in a risk to persons, the
environment and equipment.
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2.6 Labelling / Safety marks

Dial
ATEX marking:
„
II 2G c IIC TX X
II 2D c TX X
Serial number
„
The legibility of the marking must be observed during time in use but at least during inspec-
tion periods of three years. If any harm of the legibility is found please contact the manufac-
turer to renew the marking.
8
Maximum permissible surface temperature of the
instrument (for the end application)
< 2/3 T
cloud
< T − 75 K − (reduction depending on the layer thickness)
layer
Take sufficient precautionary measures.
WIKA operating instructions pressure gauge, model 632.51 per ATEX