WIKA TR21-A, Operating Instructions Manual

Page: 14 / 76

EN
14170746.05 03/2022 EN/DE/FR/ES
WIKA additional information model TR21 (Ex i) 14
■
Model TR21-C
4. Special conditions for safe use (X conditions)
1. Thermal backflow from the process, that exceeds the permissible ambient temperature
of the transmitter or the cases, must not occur and must be prevented by the installation
of suitable heat insulation or a neck tube of suitable length.
2. The wall thickness is greater than 0.2 mm and less than 1 mm. Thus the instruments
must not be subjected to ambient stresses that may have an adverse effect on the
partition. Alternatively, a thermowell of suitable minimum wall thickness may be used.
3. When using a thermowell/neck tube, the overall instrument must be designed such that
it allows installation in a way that results in a sufficiently tight gap (IP67) or a flameproof
gap (EN/IEC 60079-1) towards the less hazardous area.
4. The ambient temperature range (T
a
) for variants with optional connection cable with
moulded M12 x 1 connector is limited to -20 ... +80 °C.
5. The ambient temperature range (T
a
) for variants with optional EN 175301 M12 adapters
is limited to -40 ... +85 °C.
associated
electrical
equipment
Intrinsically safe
supply or suitable
barrier
fully in z
one 0 or 20, marking 1G or 1D
fully in z
one 1 or 21, marking 2G or 2D
Zone 0 Zone 20
Zone 1, marking 1/2G Zone 21, marking 1/2D
Separ
ation of Ex z
ones
14103747.01
Non-hazardous
area
Hazardous
area
Hazardous area
Non-
hazardous
area
Hazardous
area
Intrinsically safe
supply or suitable
barrier
Intrinsically safe
supply or suitable
barrier
Intrinsically safe
supply or suitable
barrier
Intrinsically safe
supply or suitable
barrier
Process
connection welded
3. Commissioning, operation / 4. Special conditions for safe ...