WIKA TR25 - Handbuch (Seite 16)

14073045.01 10/2013 GB/D
16 WIKA operating instructions model TR25 (Ex i)
GB
Protective measures for applications that require EPL Ga or Gb:
Operational friction or impact between equipment parts made of light metals or their alloys (e.g.
aluminium, magnesium, titanium or zirconium) with equipment parts made of iron/steel is not
permitted. Operational friction or impact between two light metals is permitted.
7.1.2 Ex marking
For applications without transmitter (digital displays) requiring instruments of equipment Group II
(potentially explosive gas atmospheres), the following temperature class classification and
ambient temperature ranges apply:
Table 1
Marking Temperature
class
Ambient tempera-
ture range (T
a
)
Max. surface temperature (T max )
at the sensor or thermowell tip
II 1G Ex ia IIC T6 Ga
II 1/2G Ex ib IIC T6 Ga/Gb
T6 (-50) 1) -40 ... +80 °C TM (temperature of the medium) +
self-heating
For this, the special conditions (17)
must be observed.
II 1G Ex ia IIC T5 Ga
II 1/2G Ex ib IIC T5 Ga/Gb
T5 (-50) 1) -40 ... +95 °C
II 1G Ex ia IIC T4 Ga
II 1/2G Ex ib IIC T4 Ga/Gb
II 1G Ex ia IIC T3 Ga
II 1/2G Ex ib IIC T3 Ga/Gb
T4, T3 (-50) 1) -40 ... +100 °C
1) The values in brackets apply to special designs. These sensors are manufactured using special sealing
compounds. Moreover, they feature housings made of stainless steel and cable glands for low-temperature
ranges
When there is a built-in transmitter and/or a digital display, the special conditions from the type
examination certificate (see item 17) apply.
For applications requiring instruments of equipment Group II (potentially explosive dust
atmospheres), the following surface temperatures and ambient temperature ranges apply:
Table 2
Marking Power P
i
Ambient
temperature
range (T a )
Max. surface temperature
(T
max
) at the sensor or
thermowell tip
II 1D Ex ia IIIC T65 °C Da
II 1/2D Ex ib IIIC T65 °C Da/Db
750 mW (-50) 1) -40 ... +40 °C TM (temperature of the medium)
+ self-heating
For this, the special conditions
(17) must be observed.
II 1D Ex ia IIIC T95 °C Da
II 1/2D Ex ib IIIC T95 °C Da/Db
650 mW (-50) 1) -40 ... +70 °C
II 1D Ex ia IIIC T125 °C Da
II 1/2D Ex ib IIIC T125 °C Da/Db
550 mW (-50) 1) -40 ... +100 °C
1) The values in brackets apply to special designs. These sensors are manufactured using special sealing
compounds. Moreover, they feature housings made of stainless steel and cable glands for low-temperature
ranges.
When there is a built-in transmitter and/or a digital display, the special conditions from the type
examination certificate (see item 17) apply.
7. Information on mounting and operation in hazardous areas