Faults - Wika Tr31-3 Betriebsanleitung

13. Faults

13. Faults
Faults
No signal/line break
Erroneous measured
values
Erroneous measured
values (too low)
Erroneous measured
values and response
times too long
Display of measured
value jumps
Corrosion
Signal interference
WIKA operating instructions models TR31-3, TR31-K (Ex i)
Causes
Mechanical load too
high or overtemperature
Sensor drift caused by
overtemperature
Sensor drift caused by
chemical attack
Entry of moisture into
cable
Wrong mounting
geometry, for example
mounting depth too
deep or heat dissipation
too high
Deposits on the
thermowell
Cable break in
connecting cable or
loose contact caused by
mechanical overload
Composition of the
medium not as expected
or modified
Stray currents caused
by electric fields or earth
loops
Earth loops
Measures
Replace the sensor with a
suitable version
Replace the sensor with a
suitable version
Analyse the medium
Use the appropriate IP
protection
The temperature-sensitive
area of the sensor must
be inside the medium, and
surfaces measurements
must be ungrounded
Remove deposits
Replace the sensor or use
thicker conductor cross-
section
Analyse the medium
Use of screened
connecting cables,
increase in the distance to
motors and power lines
Elimination of potentials,
use of galvanically isolated
transmitter supply isolators
or transmitters
EN
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