Flowserve Logix MD+ ValveSight - Manual (Page 80)

ValveSight™ Diagnostics DTM Manual for Logix MD+ Positioner with HART®
FCD- LGENSF0014-00
© Flowserve Corporation
80
Relay Response limits. Check supply pressure. Check the spool or
poppet for debris, oil, corrosion, ice on the spool. Clean or replace the
spool or poppet assembly. Replace the piezo or driver module
assembly. Maintain a clean, water-free air/gas supply.
Piezo Volts High
•
Definition: The voltage driving the piezo is above the warning limit.
•
Implications: This could indicate an error with the relay or the main
board. This may result from an extended period of inactivity, but in this
case should not persist for more than 30 minutes when the valve is
controlling. The positioner may still be functioning, but have reduced
performance under some circumstances.
•
Possible Solutions: Ensure the supply pressure is not low. If alarm
persists for more than 30 minutes, the Piezo assembly is
damaged. Replace the pilot relay.
Piezo Volts Low
•
Definition: The voltage to the piezo is too low.
•
Implications: The piezo may be damaged. This may prevent the
proper failure position upon loss of signal/power. This condition may
occur briefly on an air-to-close valve that is held for long periods of time
in the closed position, or an air-to-open valve held in the open position.
•
Possible Solutions: Ensure the supply pressure is not low. If alarm
persists for more than 30 minutes, the Piezo assembly is
damaged. Replace the pilot relay.
Temperature High
•
Definition: The temperature of the internal electronics has exceeded
the manufacturer set limit of 85°C (176°F). High temperature may affect
performance or limit the life of the positioner.
•
Possible Solutions: Regulate the temperature of the positioner by
shading or cooling supply gas. If the temperature reading is in error,
replace the main board.
Temperature Low
•
Definition: The temperature of the internal electronics has exceeded
the manufacture set limit of -40°C (-40°F). Low temperature may inhibit
responsiveness and accuracy.
•
Possible Solutions: Regulate the temperature of the positioner. If the
temperature reading is in error, replace the main circuit board.
Air Supply Humid
•
Definition: The supply gas has high relative humidity which can lead to
condensation on electronic components and failure of electronic
functions.
•
Possible Solutions: Ensure supply gas is clean and dry. Check and
clean the regulator filter.
Aux. Card 1 Fail
•
Definition: Auxiliary Card 1 is not communicating.
•
Possible Solutions: Check auxiliary card connection to the main
board. If the problem persists, replace the card.