Instruction Manual
D103785X012
Configuration
June 2017
34
Partial Stroke Test (PST) (Instrument Level ODV only)
Field Communicator
Configure > Manual Setup > Partial Stroke (2-2-6)
Note
Partial Stroke is only available for instrument level ODV.
Partial Stroke Test (PST)
D
PST Pressure Limit
—
This defines the actuator pressure at which a partial stroke test will abort. This prevents the
DVC6000 HW2 from exhausting (or building) excessive pressure to the actuator in an attempt to move a stuck
valve. During Device Setup or Auto Travel Calibration, the Partial Stroke Pressure Limit will be set automatically as
follows:
Single Acting Actuators
- For those actuators that exhaust pressure from the partial test start point, the Pressure
Limit will be a minimum value. For those actuators that build pressure from the partial test start point, the Pressure
Limit will be a maximum value.
Double Acting Actuators
- The Pressure 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 valve for actuators where the partial stroke start point is the same as the Zero
Power Condition.
The pressure signal used to determine this parameter 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
To manually set the partial stroke pressure limit, you must examine current partial stroke test results using ValveLink
software. The following steps will guide you through the process:
1. Connect the DVC6000 HW2 to a system running ValveLink software.
2. Disable the following parameters:
D
Travel Deviation Alert - set to 125%.
D
End Point Pressure Control - disable
D
Partial Stroke Pressure Limit - disable by setting the appropriate value shown in table 3‐6.
