Faults - Obsolete 54 Mode D'emploi

7. Maintenance and cleaning / 8. Faults
GB

8. Faults

Faults
No signal/ line
breakage
Erroneous measured
values
Erroneous measured
values (too low)
Erroneous measured
values and response
times too long
Measurement signal
"comes and goes"
Corrosion
12
Residual media in dismounted instruments can result
■
in a risk to persons, the environment and equipment.
Take sufficient precautionary measures.
For information on returning the instrument see chapter
9.2 "Returns".
Causes
Mechanical load too high
or overtemperature
Sensor drift caused by
overtemperature
Sensor drift caused by
chemical attack
Entry of moisture into
cable or measuring insert
Wrong mounting geome-
try, for example mounting
depth too deep or heat
dissipation too high
Deposits on the sensor or
thermowell
Cable break in connecting
cable or loose contact
caused by mechanical
overload
Composition of the medium
not as expected or modified
or wrong thermowell
material selected
WIKA operating instructions model 54, Twin-Temp
Measures
Replace probe or measuring
insert with a suitable design
Replace probe or measuring
insert with a suitable design
Use a design with
thermowell
Replace probe or measuring
insert with a suitable design
Temperature-sensitive area
of the sensor must be inside
the medium, and surfaces
must be isolated
Remove deposits
Replace probe
Analyse medium and then
select a more-suitable
material or replace
thermowell regularly