Temperature head transmitter
9 Fault finding
29
9.3
Fault finding and repairs
Fault finding and repairs
Trouble shooting on RTDs (Pt100/Pt500/Pt1000/Ni100)
Trouble shooting for thermocouple connection (TC)
Fault
Cause
Action/cure
Current (
≥
21 mA)
Sensor defective
Check sensor
Incorrect RTD connection
Connect the cables correctly
(see connection diagram)
Incorrect 2 wire connection
Connect the cables correctly
(polarity, see terminal layout)
No power supply on the 2 wire
connection
Check current loop; the supply
should be >8 V
Head transmitter defective
Replace head transmitter
Incorrect or inaccurate measured
value
Sensor is incorrectly installed
Reinstall sensor correctly
Heat dissipation via sensor
Monitor sensor installation posi-
tioning
Sensor connection (2 wire)
Monitor sensor connection
Fault
Cause
Action/cure
Current (
≥
21 mA)
Incorrect sensor connection
Connect the cables correctly
(polarity, see terminal layout)
Sensor defective
Check sensor
Incorrect 2 wire connection
(current loop)
Connect the cables correctly
(polarity, see terminal layout)
No power supply on the 2 wire
connection
Check current loop; the supply
should be >8 V
Head transmitter defective
Replace head transmitter
Incorrect or inaccurate measured
value
Sensor is incorrectly installed
Reinstall sensor correctly
Heat dissipation via sensor
Monitor sensor installation
positioning
Fault due to the thermo wire
welded to the well (interference
voltages incurred)
Please use a sensor in which the
thermo wire in not welded