Emerson Rosemount 3095, Reference Manual, Page: 112 / 130

Reference Manual
00809-0100-4716, Rev JA
May 2008
Rosemount 3095 MultiVariable
5-6
Table 5-6. Unexpected Process Variable (PV) Readings
Symptom Corrective Action
High PV Reading DIFFERENTIAL PRODUCER
• Check for restrictions at the differential producer.
• Check the installation and condition of the differential producer.
• Note any changes in process fluid properties that may affect output.
IMPULSE PIPING
• Check to ensure that the pressure connection is correct.
• Check for leaks or blockage.
• Check to ensure that blocking valves are fully open.
• Check for entrapped gas in liquid lines and for liquid in gas lines.
• Check to ensure that the density of fluid in impulse lines is unchanged.
• Check for sediment in the transmitter process flange.
• Make sure that process fluid has not frozen within the process flange.
POWER SUPPLY
• Check the output voltage of the power supply at the transmitter. It should be 11 to 55 V dc for HART (9 to 32 V dc
for fieldbus) with no load at the transmitter terminals.
Note: do not use higher than the specified voltage to check the loop, or damage to the transmitter may
result.
TRANSMITTER ELECTRONICS
• Connect a personal computer and use the EA Software to check the sensor limits to ensure calibration
adjustments are within the sensor range and that calibration is correct for the pressure being applied.
• Connect a personal computer and using the EA Software, select Diagnostics, Error Info
to detect any electronic failures.
• Make sure the post connectors are clean.
• Confirm that the electronics housing is properly sealed against moisture.
• If the electronics are still suspect, substitute new electronics.
SENSING ELEMENT
• The sensing element is not field repairable and must be replaced if found to be defective. Check for obvious
defects, such as a punctured isolating diaphragm or fill fluid loss, and contact your nearest Rosemount Service
Center.