WIKA TR25 Manual De Instrucciones página 28

9. Faults
For contact details see chapter 1 "General information" or the back page of
the operating instructions.
EN
Faults
No signal/
Cable 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
28
Causes
Mechanical load too high or
overtemperature
Sensor drift caused by
overtemperature
Entry of moisture into cable
Wrong mounting geometry or heat
dissipation too high
Deposits within the thermowell
Cable break in connection cable
or loose contact caused by
mechanical overload
Composition of the medium not
as expected or modified or wrong
thermowell material selected
Stray currents caused by electric
fields or earth circuits
Earth circuits
Measures
Replacement of the resistance
thermometer
Replacement of the resistance
thermometer
Replacement of the resistance
thermometer
The temperature-sensitive area
of the sensor must be inside the
medium. Beware of the mounting
position of the sensor!
Remove deposits
Check supply line
Analyse medium and then select a
more suitable material or replace
thermowell regularly
Use of shielded connection leads,
increase in the distance to motors
and power lines
Elimination of potentials, use of
galvanically isolated barriers or
transmitters
WIKA operating instructions model TR25 (Ex i)