Emerson Rosemount 5408 Reference Manual page 103

Reference Manual
00809-0100-4408, Rev BA
Table 7-7. Troubleshooting the 4-20 mA/HART Output
Symptom
Transmitter milliamp reading is zero.
Transmitter milliamp reading is too low or high.
Milliamp reading is erratic.
Transmitter will not respond to changes in level.
There is no HART communication (lost device
communication).
Service and Troubleshooting
Recommended actions
Verify power is applied to signal terminals.

Verify power supply voltage is adequate at signal terminals, see

supply" on page 60.
Verify transmitter and power supply are properly grounded.

Verify level.

Check the settings of the 4-20 mA range values,

value" on page 188.
Verify output is not in alarm condition.

Check that power wires are connected to the correct signal terminals.

Perform Calibrate Analog Out, see

Verify power supply voltage is adequate at signal terminals, see

supply" on page 60.
Check for external electrical interference.

Verify transmitter is properly grounded.

Verify shield for twisted pair is only grounded at the power supply end.

Under turbulent conditions with low level rates, consider increasing the

Damping value.
Verify level is between the 4 and 20 mA set points.

Verify output is not in alarm condition.

Verify transmitter is not in loop test or simulation mode.

Verify power supply voltage is adequate at signal terminals, see

supply" on page 60.
Check load resistance (250 ohms minimum).

Check if transmitter is at an alternate HART address.

Check current analog output value to verify that transmitter hardware

works.
Verify the blue plug is attached to the TEST terminal (if applicable).

When unplugged, HART communication to configuration tool may be
compromised.
Service and Troubleshooting
November 2017
see"Upper/lower range
"Calibrate analog out" on page
"Power
102.
"Power
"Power
91