364Ax-Gx Instruction Manual
50
Troubleshooting
Suggestions for the most common operating problems are given in this User’s Manual.
If you su spect malfunction despite the absence of any diagnostic messages on the display, follow t he
procedures described here to verify that transmitter hardware and process connections are in good working
order.
Simple fault finding
In case the transmitter is not working properly, carry out the following fault finding checks before contacting
your nearest Service Center.
WARNING
If the transmitter is working in a control loop, the loop must be placed under local manual control
while the instrument is examined or taken out of service. Take all precautions to avoid damages
caused by pressure or dangerous fluids release.
Symptom
Corrective actions
Check the transmitter power supply
Verify terminal voltage is 10.5 to 42 V dc (or 30Vdc in Ex ia
applications)
Check power wires for reversed polarity
Clean the electrical connections
No output current
Replace the Electronics module
Check the transmitter power supply
Verify applied pressure
Verify 4 and 20 mA range points
Verify output is not in alarm condition
Verify if 4 – 20 mA output trim is required
Check for trapped gas in liquid lines and liquid in dry lines
Check for sediment in process flanges
Clear the electronics module connectors contact
High, low or irregular output current
Replace the Electronics module
Verify the output is between 4 and 20 mA or saturation levels
Verify clean DC Po wer to transmitter (Ma x AC noise 0.2 volts
peak to peak
Check loop resistance, 250 ohm minimum
Transmitter Not Communicating with HART
Communicator
Check if unit is addressed properly
Check the test equipment
Check impulse piping or manifold for blockage
Verify applied pressure is between the Lower Range Limit and
the Upper Range Limit
Verify output is not in alarm condition
Transmitter will not respond to changes in
applied pressure
Verify transmitter is not in Loop Test mode
Check application for faulty equipment in pressure line
Verify transmitter is n ot reacting directly to equipment turning
on/off
Digital Pressure Variable reading is erratic
Verify damping is set properly for application
Verify power source to transmitter has adequate voltage and
current
Check for external electrical interference
Verify transmitter is properly grounded
Milliamp reading is erratic
Verify shield for twisted pair is only grounded at one end
