1. Ex marking
For applications without transmitters (models TR21-x-xPx and TR21-x-xRx) that require
group II instruments (potentially explosive gas atmospheres), the following temperature
class classification and ambient temperature ranges apply:
Table 1
Marking
ATEX
IECEx
II 1G
Ex ia IIC T1, T2 T3, T4,
T5, T6 Ga
II 1/2G Ex ia IIC T1, T2, T3, T4,
T5, T6 Ga/Gb
II 2G
Ex ia IIC T1, T2, T3, T4,
T5, T6 Gb
For applications requiring instruments of equipment group II (potentially explosive dust
atmospheres), the following surface temperatures and ambient temperature ranges apply:
Table 2
Marking
ATEX
IECEx
II 1D
Ex ia IIIC T135 °C Da
II 1/2D Ex ia IIIC T135 °C Da/Db
II 2D
Ex ia IIIC T135 °C Db
WIKA additional information model TR21 (Ex i)
Temperature
Ambient
class
temperature
range (T
T1 ... T5
-50 ... +85 °C
T6
-50 ... +80 °C
Power P
Ambient
i
temperature
range (T
750 mW
-50 ... +40 °C
650 mW
-50 ... +70 °C
550 mW
-50 ... +85 °C
Max. surface temperature
(T
) at the sensor or
max
)
thermowell tip
a
T
(medium temperature) +
M
self-heating
For this, the special conditions
must be observed (see chapter
4 "Special conditions for safe
use (X conditions)").
Max. surface temperature
(T
) at the sensor or
max
)
thermowell tip
a
T
(medium temperature) +
M
self-heating
For this, the special conditions
must be observed (see chapter
4 "Special conditions for safe
use (X conditions)").
EN
5