Zero Pwr Cond; Tvl Cutoff Lo; Actuator Style; Relay Type - Emerson Fisher Fieldvue DVC6030f Instruction Manual

DVC6000f Series
ACTUATOR
STEM
5
Figure 5-1. Feedback Connection for Typical Sliding-Stem
Actuator (Up to 4-inch Travel)
changed to Travel with Pressure Fallback/Auto
Recovery.
D Zero Pwr Cond
Zero Power Condition (ZERO_PWR_COND [42.2])
identifies whether the valve is open or closed when
instrument power is lost. If you are unsure how to set
this parameter, disconnect the segment loop power to
the instrument. The resulting valve travel is the Zero
Power Condition.
D Tvl Cutoff Lo
Travel Cutoff Lo (FINAL_VALUE_CUTOFF_LO [16])
defines the low cutoff point for travel, in percent.
Below this cutoff, the travel target is set to −23%. A
travel cutoff of 0.5% is recommended to help ensure
maximum shutoff seat loading. Travel Cutoff Lo is
effectively deactivated by setting it to −25%.
D Actuator Style
Select the Actuator Style (ACTUATOR_STYLE
[42.1]), spring & diaphragm, piston double-acting
without spring, piston single-acting with spring, or
piston double-acting with spring.
5-24
TRAVEL SENSOR SHAFT
FEEDBACK ARM
STEM
CONNECTOR
ADJUSTMENT ARM
29B1665-A / DOC
CONNECTOR ARM
Enter the Relay Type (RELAY_TYPE [42.5]), A or B,
installed in the digital valve controller. Relay A is for
double-acting and single-acting direct-acting
applications. Relay B is used for single-acting
reverse-acting applications.
Select the Feedback Connection(FEEDBACK_CONN
[42.4]), Rot-All, SS-roller, or SStem-Standard. For
rotary valves, enter Rot - All, SS-Roller. For
sliding-stem valves, if the feedback linkage consists of
a connector arm, adjustment arm, and feedback arm,
similar to the linkage shown in figure 5-1, enter SStem
- Standard. If the feedback linkage consists of a roller
that follows a cam, similar to the linkage shown in
figure 5-2, enter Rotary All, SStem - Roller.
Select Clockwise or Counterclockwise. Travel Sensor
Motion (TRAVEL_SEN_MOTION [42.3]) establishes
the proper valve travel sensor (feedback) rotation.
ROLLER
CAM
Figure 5-2. Feedback Connection for Typical Long-
Stroke Sliding-Stem Actuator (4 to 24-Inches Travel)
D Relay Type
D Feedback Conn
D Tvl Sen Motion
Note
The Travel Sensor Motion is set
automatically by the Setup Wizard, or
during the Auto Calibration procedure.
March 2006