WIKA 632.51 Mode D'emploi page 11

2. Safety
1. Design temperatures
Permissible ambient temperature
-20 ... +60 °C
Permissible medium temperature (instrument)
-20 ... +100 °C
The permissible medium temperature does not only depend on the instrument
design, but also on the ignition temperature of the surrounding gases, vapours or
dusts. Both aspects have to be taken into account.
The limits of the permissible temperature ranges of an "instrument hook-up"
mounting arrangement are determined, in each case, by the component with the
greatest restriction.
2. Maximum surface temperature
The surface temperature of the instruments mainly depends on the medium
temperature of the application. The instrument itself does not contain any heat
sources. For determining the maximum surface temperature, besides the medium
temperature also other influences such as the ambient temperature and, if appli-
cable, 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.
Explosive gas/air, vapour/air and mist/air atmospheres
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)
WIKA mode d'emploi manomètre, type 6 selon ATEX
Maximum permissible surface temperature
of the instrument (for the end application)
Instruments with permissible medium
temperature ≤ 100 °C
+65 °C
+80 °C
+100 °C
+100 °C
+100 °C
+100 °C
FR
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