Emerson Fisher FIELDVUE DVC6000, Инструкция по эксплуатации

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DVC6000 Digital Valve Controllers
September 2013 4-20
Figure 4-8. Feedback Connection for Typical Long-Stroke
Sliding-Stem Actuator (4 to 24 Inches Travel)
CAM
ROLLER
29B1665-A / DOC
STEM
CONNECTOR
PST Enable—Yes or No. Enables or disables
the Partial Stroke Test.
PST Variables View/Edit—Follow the prompts
on the Field Communicator display to enter or view
information for following PST Variables: Max Travel
Movement, Stroke Speed, Pause Time, PST Press
Limit, PST Mode Enable, Pressure Set Point, and End
Pt Control Enable.
Max Travel Movement—The default value for Max
Travel Movement is 10%. It may be set to a value
between 1 and 30% in 0.1% increments.
Note
The Max Travel Movement is the
percentage of total span that the valve
moves away from its operating state
towards its fail state during a Partial
Stroke Test.
Stroke Speed—The stroke speed can be set for
1%/second, 0.5%/second, 0.25%/second,
0.12%/second, or 0.06%/second. The default value for
Partial Stroke Speed is 0.25%/second.
Pause Time—The Setup Wizard sets the Partial
Stroke Pause Time to 5 seconds. This is the pause
time between the up and down strokes of the test. It
can be set for 5, 10, 15, 20 or 30 seconds.
PST Press Limit (single acting actuators)—During the
Setup Wizard, or Auto Calibration, the Partial Stroke
Pressure Limit value will be set to a positive value for
single-acting actuator. For those actuators that vent
from the test starting point, the pressure limit will be a
minimum value. For those actuators that fill from the
test starting point, the pressure limit will be a
maximum value. The pressure signal used for this
threshold depends on relay type and is summarized
below.
Relay Type Pressure Signal
A or C Port A
−
Port B
B Port B
−
Port A
B Special App. Port B
C Special App. Port A
PST Press Limit (double-acting actuators)— During
the Setup Wizard or Auto Travel Calibration, the PST
Press Limit will be set to a negative value for actuators
where the Partial Stroke Start Point is opposite of the
Zero Power Condition (e.g., Partial Stroke Start Point
= Open and Zero Power Condition = Closed) and to a
positive value for actuators where the Partial Stroke
Start Point is the same as the Zero Power Condition.
Note
In order to manually set the partial
stroke pressure limit with the correct
value, you must be able to run a valve
signature test using ValveLink
software. It is then possible to set the
partial stroke pressure limit with the
Field Communicator, using the
information generated by the valve
signature test.
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