WIKA TR25 Betriebsanleitung Seite 17

7. Information on mounting and operation in hazardous areas
When housings are used, they must either have their own suitable approval or comply
with the minimum requirements. IP protection: at least IP20 (at least IP65 for dust),
applies to all housings. However, light metal housings must be suitable in accordance with
IEC/EN 60079-0 Section 8.1. In addition, non-metallic housings or powder-coated housings
must meet the requirements of IEC/EN 60079-0 or have a suitable warning note.
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
II 1G Ex ia IIC T6 Ga
II 1/2G Ex ib IIC T6 Ga/Gb
II 1G Ex ia IIC T5 Ga
II 1/2G Ex ib IIC T5 Ga/Gb
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
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.
WIKA operating instructions model TR25 (Ex i)
Temperature Ambient
class temperature
range (T
T6 (-50)
T5 (-50)
T4, T3 (-50)
Max. surface
temperature (T
) at the sensor or
a
thermowell tip
-40 ... +80 °C T (temperature of the
1)
M
medium) + self-heating
-40 ... +80 °C
1)
For this, the special
conditions (17) must be
-40 ... +80 °C
1)
observed.
EN
)
max
17