Endress+Hauser iTEMP TMT71, Operating Instructions Manual

Page: 38 / 96

Diagnostics and troubleshooting iTEMP TMT71
38 Hauser
Application errors without status messages for RTD sensor connection
Problem Possible cause Remedy
Measured value is incorrect/
inaccurate
Incorrect sensor orientation. Install the sensor correctly.
Heat conducted by sensor. Observe the installed length of the
sensor.
Device programming is incorrect
(number of wires). Change the Connection type device
function.
Device programming is incorrect
(scaling). Change scaling.
Incorrect RTD configured. Change the Sensor type device function.
Sensor connection. Check that the sensor is connected
correctly.
The cable resistance of the sensor (2-
wire) was not compensated. Compensate the cable resistance.
Offset incorrectly set. Check offset.
Failure current (≤ 3.6 mA or
≥ 21 mA)
Faulty sensor. Check the sensor.
RTD connected incorrectly. Connect the connecting cables correctly
(terminal diagram).
Device programming is incorrect (e.g.
number of wires). Change the Connection type device
function.
Incorrect programming. Incorrect sensor type set in the Sensor
type device function. Set the correct
sensor type.

Application errors without status messages for TC sensor connection
Problem Possible cause Remedy
Measured value is incorrect/
inaccurate
Incorrect sensor orientation. Install the sensor correctly.
Heat conducted by sensor. Observe the installed length of the
sensor.
Device programming is incorrect
(scaling). Change scaling.
Incorrect thermocouple type (TC)
configured. Change the Sensor type device function.
Incorrect reference junction set. Set the correct reference junction .
Interference via the thermocouple
wire welded in the thermowell
(interference voltage coupling). Use a sensor where the thermocouple
wire is not welded.
Offset incorrectly set. Check offset.
Failure current (≤ 3.6 mA or
≥ 21 mA)
Faulty sensor. Check the sensor.
Sensor is connected incorrectly. Connect the connecting cables correctly
(terminal diagram).
Incorrect programming. Incorrect sensor type set in the Sensor
type device function. Set the correct
sensor type.