Endress+Hauser iTEMP HART Communication TMT 182 Manuel De Mise En Service page 36

4 Trouble-shooting
36
Application faults for TC connection
Fault
Fault current
≤ ≥
( 3.6 mA or 21 mA)
Measured value incorrect/
inaccurate
Cause
Sensor incorrectly connected
Defective sensor
Programming
Incorrect 2 wire connection
(current loop)
Defective head transmitter
Faulty sensor installation
Heat conducted via sensor
Transmitter programming faulty
(scale)
Incorrect thermocouple set up
Incorrect cold junction set up
Offset incorrectly set up
Fault on the thermowell welded
thermo wire (coupling of
interference voltages)
iTEMP® HART® Communication
Action/cure
Connect sensor correctly to
terminal plan (polarity)
Replace sensor
Sensor type 'RTD' set-up; set up
correct thermocouple
Connect the cables correctly
(see connection diagram)
Replace head transmitter
Install sensor correctly
Take note of sensor installation
length
Change scale
Change parameter 'Sensor type'
See chapter 'Operation' and
'Techn. data'
Check offset
Use sensor where the thermo
wire is not welded
Endress+Hauser