Fisher FIELDVUE DVC6200f Instruction Manual page 67

Instruction Manual
D103412X012
If after completing initial setup and calibration the valve cycles or overshoots, or is sluggish, you can improve
operation by running Stabilize/Optimize.
Stabilize/Optimize is included with the device description (DD) firmware. Stabilize/Optimize is accessible from the
transducer block and permits changing the transducer block set point a small amount to see if the valve is unstable or
unresponsive. If valve response is unsatisfactory, the method permits adjusting the digital valve controller tuning to
improve response.
If the valve is unstable, select Decrease Response to stabilize valve operation. This selects the next lower tuning set
(e.g., F to E). If the valve response is sluggish, select Increase Response to make the valve more responsive. This selects
the next higher tuning set (e.g., F to G).
If after selecting Decrease Response or Increase Response the valve travel overshoot is excessive, Increase Damping or
Decrease Damping can be used to select a damping value not represented in a predefined tuning set. Select Decrease
Damping to select a damping value that allows more overshoot. Select Increase Damping to select a damping value that
will decrease the overshoot.
When valve operation is satisfactory, select Exit. Before exiting, you are asked if you want to return the transducer
block mode to Auto. Select Yes to change the transducer block mode to Auto. Select No to leave the transducer block
in its current mode.
Pressure Tuning
TB > Configure/Setup > Detailed Setup > Response Control > Pressure Tuning
Field Communicator
WARNING
Changes to the tuning set may cause the valve/actuator assembly to stroke. To avoid personal injury or property damage
caused by moving parts, keep hands, tools, and other objects away from the valve/actuator assembly.
D Pressure Tuning Set
There are twelve Pressure Tuning Sets (PRESS_TUNING_SET [42.11]) to choose from. Each tuning set provides a
preselected value for the digital valve controller gain settings.
Tuning set C provides the slowest response and M provides the fastest response. Tuning set B is appropriate for
controlling a pneumatic positioner. Table 4‐9 lists the proportional gain, pressure integrator gain and minor loop
feedback gain values for preselected tuning sets.
In addition, you can specify Expert tuning and individually set the pressure proportional gain, pressure integrator gain,
and pressure minor loop feedback gain. Individually setting or changing any tuning parameter will automatically
change the tuning set to X (expert).
Detailed Setup—Transducer Block
July 2013
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