Troubleshooting Valve Control - GE FVP110 Maintenance Manual

GE Energy

Troubleshooting Valve Control

Problem
A change in setpoint
causes no action of the
valve.
The valve's full stroke is
insufficient for the setpoint
input.
Table 57 Troubleshooting Valve Control
Presumed Cause
Air piping is incorrect.
The instrument is in FAILSAFE
state.
Air supply is not being fed.
The valve has failed.
The I/P module or control relay
has failed, or there is breakage
in the cable between the I/P
module and control relay.
The air supply pressure is not
high enough to drive the valve
actuator.
The range of the setpoint is
limited by software.
FVP 110 Fieldbus Valve Positioner Manual
Remedy
Correct piping.
Write Clear non-latch to
RELEASE_FAILSAFE
parameter.
Supply proper air
pressure.
Apply a pneumatic
pressure directly to the
valve actuator and check
whether there is valve
action.
If the output pressure does
not increase even though
the
SERVO_OUTPUT_SIGN
AL value is at maximum,
contact the nearest
service station or
representative office.
Check the air supply
pressure rating for the
valve actuator and supply
air at the correct pressure,
and write 4 or 2 to
AUTO_TUNE_EXEC to
redo Autotuning.
Check the values of
SP_HI_LIM and
SP_LO_LIM in the AO
block and
FINAL_VALUE_RANGE in
the transducer block.
178
See Section
"Piping" on
page 52
"Fail-safe Action"
on page 131
"Piping" on
page 52
"A/M Switching"
on page 42
—
❑
"Piping" on
page 52
❑
"Carrying out
Tuning" on
page 61
❑
"Forward
Path" on
page 134
❑
"Function
Block Parame-
ters" on
page 183