Emerson Fisher FIELDVUE DVC6000, Инструкция по эксплуатации

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Detailed Setup
September 2013 4-21
To manually set the partial stroke pressure limit,
disable the travel deviation alert by setting Travel Dev
Alert Pt to 125%. Also disable “end point pressure
control” and disable the partial stroke pressure limit by
setting the values shown in table 4-9.
Run the partial stroke test using the Field
Communicator. Once the test is completed download
the partial stroke test results using ValveLink software.
Select the Press/Time radio button from the partial
stroke valve signature graph. If actuator pressure
starts high and moves low, find the minimum actuator
pressure, Pmin. Otherwise, find the maximum actuator
pressure, Pmax. Use table 4-10 to estimate the partial
stroke pressure limit.
The default value is 0.
For double-acting valves, the differential pressure is
used.
Table 4-9. Values for Disabling Partial Stroke Pressure Limit
Actuator
Type
Relay Type
Zero
Power
Condition
Partial
Stroke
Start Point
Partial
Stroke
Pressure
Limit
(Disabled)
Single-
Acting
A or C
Closed
Open 0.0
Closed Psupply
Open
Open Psupply
Closed 0.0
B
Closed
Open Psupply
Closed 0.0
Open
Open 0.0
Closed Psupply
Double-
Acting
A
Closed
Open
−
Psupply
Closed Psupply
Open
Open Psupply
Closed
−
Psupply
Table 4-10. Estimates for Partial Stroke Pressure Limits
Actuator Style Relay Type
Zero Power
Condition
PST Starting Point Partial Stroke Pressure Limit
(1)
Spring and
Diaphragm
A or C
Closed
Open Pmin
−
0.25 * (Bench Set High
−
Bench Set Low)
Closed Pmax + 0.25 * (Bench Set High
−
Bench Set Low)
Open
Open Pmax + 0.25 * (Bench Set High
−
Bench Set Low)
Closed Pmin
−
0.25 * (Bench Set High
−
Bench Set Low)
B
Closed
Open Pmax + 0.25 * (Bench Set High
−
Bench Set Low)
Closed Pmin
−
0.25 * (Bench Set High
−
Bench Set Low)
Open
Open Pmin
−
0.25 * (Bench Set High
−
Bench Set Low)
Closed Pmax + 0.25 * (Bench Set High
−
Bench Set Low)
Single-Acting Piston
A or C
Closed
Open 0.5 * Pmin
Closed Pmax + 0.5 * (Psupply
−
Pmax)
Open
Open Pmax + 0.5 * (Psupply
−
Pmax)
Closed 0.5 * Pmin
B
Closed
Open Pmax + 0.5 * (Psupply
−
Pmax)
Closed 0.5 * Pmin
Open
Open 0.5 * Pmin
Closed Pmax + 0.5 * (Psupply
−
Pmax)
Double-Acting
Piston
A
Closed
Open Pmin
−
0.5 * (P Pmin)
Closed Pmax + 0.5 * (Psupply
−
Pmax)
Open
Open Pmax + 0.5 * (Psupply
−
Pmax)
Closed Pmin
−
0.5 * (P Pmin)
4