WIKA 55 - Page 9

EN
11583747.07 12/2021 EN/DE/FR/ES
WIKA additional operating instructions model 55 (ATEX) 9
3. Special conditions for use (X conditions)
3. Special conditions for use (X conditions)
1) Design temperatures
Permissible ambient temperature at case:
Temperature ranges
Unlled instrument -40 ...+70 °C
Filled instrument -40 ... +70 °C
Option: low temperature -50 ... +70 °C
Option: POLARgauge
®
-70 ... +60 °C
Permissible medium temperature: max. end of scale
Observe the surface temperature for ATEX application:
The permissible medium temperature does not only depend on
the instrument design, but also on the ignition temperature of the
surrounding gases, vapours or dust. Take both aspects into account.
2) Maximum surface temperature
The surface temperature mainly depends on the medium and
ambient temperature. The instrument itself does not contain any
heating sources. 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.
Instruments for use in hazardous gas/air, vapour/air and mist/air
atmospheres:
Temperature class
(gas application)
Maximum permissible surface
temperature (for the end application)
T6 80 °C
T5 95 °C
T4 130 °C
T3 195 °C
T2 250 °C (290 °C)
1)
T1 250 °C (440 °C)
1)
1) only for instruments without liquid lling