WIKA NS 100 Mode D'emploi page 12

2. Safety
Maximum surface temperature
The surface temperature of the instruments mainly depends on the
medium temperature of the application. The instrument itself does not
EN
contain any heat sources. For determining the maximum surface temper-
ature, besides the medium temperature also other influences such as
the ambient temperature and, if applicable, the solar irradiation must
be taken into account. For prevention, consider the maximum medium
temperature as maximum surface temperature, if it is not possible to
determine the real surface temperature even in the case of expected
malfunctions.
Potentially explosive gas atmosphere
Required
temperature
class (ignition
temperature of
gas or vapour)
T6 (T > 85 °C)
T5 (T > 100 °C)
T4 (T > 135 °C)
T3 (T > 200 °C)
T2 (T > 300 °C)
T1 (T > 450 °C)
Hazardous dust atmosphere
For dusts, the procedure specified in ISO/IEC 80079-20-2 for determin-
ing 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 thick-
ness per IEC/EN 60079-14.
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Maximum permissible surface temperature of
the instrument (for the end application)
Models 232, 262,
PG23CP, PG28
(unfilled instruments)
+65 °C
+80 °C
+105 °C
+160 °C
+200 °C
+200 °C
WIKA operating instructions pressure gauge, model 2 per ATEX
Models 233, 263,
PG23LT, PG23CP, PG28
(filled instruments)
+65 °C
+80 °C
+100 °C
+100 °C
+100 °C
+100 °C