Rosemount Model 3095 Multivariable
™
Level Controller
5-6
TABLE 5-5. Unexpected Process
Variable (PV) Readings.
Symptom Corrective Action
High PV Reading IMPULSE PIPING
• Check to ensure that the process 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 device process flange.
• Make sure that process fluid has not frozen within the
process flange.
POWER SUPPLY
CAUTION
Do not use higher than the specified voltage to check the loop
or damage to the device may result.
• Check the output voltage of the power supply at the device. It
should be 11 to 55 V dc at the device terminals.
DEVICE ELECTRONICS
• Connect a Model 275 to check the sensor limits to ensure
calibration adjustments are within the sensor range and that
calibration is correct.
• 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.
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