SMAR ld301, Operation And Maintenance Instruction Manual

Page: 53 / 70

Maintenance Procedure
5.3
Electronic Circuit Failure
•
Locate the failure by alternately testing the transmitter circuit and the interface with spare parts.
Transmitter Address
•
Check if the transmitter address is compatible with the one expected by the configurator.
Symptom : CURRENT OF 21.0 mA or 3.6 mA
Probable Source of Trouble :
Pressure Tap (Piping)
•
Verify if blocking valves are fully open.
•
Check for gas in liquid lines or for liquid in dry lines.
• Check the specific gravity of process fluid.
•
Check process flanges for sediments.
•
Check the pressure connection.
•
Check if bypass valves are closed.
•
Check if pressure applied is not over upper limit of transmitter's range.
Sensor to Main Circuit Connection
•
Check connection (male and female connectors).
Electronic Circuit Failure
•
Check the sensor circuit for damage by replacing it with a spare one.
•
Replace sensor.
Symptom : INCORRECT OUTPUT
Probable Source of Trouble :
Transmitter Connections
•
Check power supply voltage.
•
Check for intermittent short circuits, open circuits and grounding problems.
Noise Measurement Fluid
•
Adjust damping
Pressure Tap
•
Check for gas in liquid lines and for liquid in steam or gases lines.
•
Check the integrity of the circuit by replacing it with a spare one.
Calibration
•
Check calibration of the transmitter.
NOTE:
A 21.0 or 3.6 mA current indicates that the transmitter is in Burnout (TRM) or safety
output (PID). Use the configurator to investigate the source of the problem.
Symptom
:
DISPLAY INDICATES "FAIL SENS"
Probable Error Source
:
Sensor Connection to the Main Board
Check the connection (flat cable, male and female connectors).
Type of Sensor Connected to the Main Board
Check if the sensor connected to the main board is the one specified for the LD301 model:
sensor type shall be hyper - High Performance.
Electronic Circuit Failure
Check if the sensor set is damaged, replacing it for a spare one.
NEW