Information On Mounting And Operation In Hazardous Areas - Wika Tr31-3 Betriebsanleitung

10. Information on mounting and operation in ...
10. Information on mounting and operation in
hazardous areas
EN
10.1 General information on explosion protection
For the installation of the thermometers, only components (e.g.
■
cables, cable glands, etc.) permitted for "intrinsic safety" may be used.
For grounding the conductive screen, follow the specifications of
■
EN/IEC 60079-14.
The temperature resistance of the connecting cable must match the
■
permissible operating temperature of the cases.
For ambient temperatures above 60 °C, heat-resistant connecting
cable must be used (see table in chapter 4 "Design and function").
Mounting within metallic enclosures:
■
The case must be grounded against electromagnetic fields and
electrostatic discharge. It does not have to be connected separately
to the equipotential bonding system. It is sufficient if the metallic
thermowell has a solid and secured contact with the metallic vessel or
its structural components or pipelines, so long as these components
are connected to the equipotential bonding system.
Mounting within non-metallic enclosures:
■
- Ground the cable shield at one end, preferably in the safe, and so
non-Ex, area (EN 60079-14). For instruments with cable output,
the shield is connected to the case. The simultaneous connection
of the case and the cable shield to ground is only permitted if any
accidental energisation between the shield connection (e.g. at the
power supply) and the case can be excluded (see EN 60079-14).
- Power the resistance thermometer via an intrinsically safe current
circuit (Ex ia).
- Both the effective internal capacitance and inductance must be
considered
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The requirements of the ATEX directive must be followed.
Additionally the specifications of the respective national
regulations concerning Ex usage (e.g. EN/IEC 60079-10 and
EN/IEC 60079-14) apply.
WIKA operating instructions models TR31-3, TR31-K (Ex i)