Operate
6.2 Parameter description
SITRANS VP300 with or without HART
102
Operating Instructions, 03/2011, A5E01258666-03
"3.5.4 PST Reference"
Purpose of the "PST reference" submenu
In this menu, you read off the results of the reference stroke. A reference stroke provides
information on the required breakaway time, stroke time, and total time. The reference stroke
is the basis for setting the associated thresholds, which can also be set in this menu. If the
thresholds are exceeded, a failure reaction is triggered. You specify how the positioner is to
react in the "3.5.2.8 Failure reaction" (Page 100) parameter. The following table contains an
overview of the menus and parameters:
3.5.4.1 Breakaway time
3.5.4.4 Threshold stroke time
3.5.4.2 Threshold breakaway time
3.5.4.5 Total time
3.5.4.3 Stroke time
3.5.4.6 Threshold total time
"3.5.4.1 Breakaway time"
Requirements:
Reference stroke has been initiated.
"3.5.3 Initiate reference stroke" (Page 101)
Factory setting:
0.0 s
Display range:
0.0 ... 100.0
Purpose:
Indicates the breakaway time of the reference stroke.
Description:
Breakaway time is the time that the valve requires until a movement is
discontinued. The breakaway time is measured after a valve
movement of 0.5%.
"3.5.4.2 Threshold breakaway time"
Factory setting:
2.0 s
Setting range:
0.1 ... 100.0
Purpose:
The tight closing function is set to "Up and down" in the event of a
fault independent of the previous setting in the "Tight closing"
parameter.
"3.5.4.3 Stroke time"
Requirements:
Reference stroke has been initiated.
"3.5.3 Initiate reference stroke" (Page 101)
Factory setting:
0.0 s
Display range:
0.0 ... 100.0
