Fsts And Model 3711 Points; Fst Editor - Emerson Micro Motion 3711 Configuration And Use Manual

Function Sequence Tables
Depending on the function, the RR and the CF may be loaded, stored, tested, modified, or left
unchanged.
11.3

FSTs and Model 3711 points

FSTs may read and write to several different point types in Model 3711 memory. The following three
point types require special attention during FST development:
• History points – Used to store data in the history database. The history points must be defined
before the FST is coded, and must be one of the following types:
- FST Data
- FST Time – Second
- FST Time – Minute
Note: Although it is possible to use an FST to write history data, it is very infrequent. Micro Motion
recommends using standard or extended history points to write required history. The predefined
standard history points will cover most history requirements, and additional history points can be
defined if other types of data are needed. See Section 8.3.
Note: If you will use an FST to write history data, Micro Motion recommends that at least one history
point be defined as FST Time to provide a timestamp for other history records written by the FST.
• FST registers – Several points have been predefined in Model 3711 memory for FST use.
These points store data, timers, messages, etc. Depending on requirements, the FST can
initialize an FST register with a value, or ROCLINK 800 can be used to define a startup value
for an FST register (see Section 11.5, Step 2).
FST registers are typically used for intermediate results during FST processing, and to pass
values from one FST to another. FST registers can also be accessed by a Modbus program or a
PID control loop.
• Soft points – A soft point is a user-defined point used for storing floating-point data. Soft
points are predefined in the Model 3711 memory. Depending on requirements, the FST can
initialize a soft point with a value, or ROCLINK 800 can be used to define a startup value for a
soft point. See Appendix D for more information on soft points, and for information on
accessing soft points with ROCLINK 800.
Soft points can be used for intermediate results if necessary, that is, if no FST registers are
available. Soft points are also used to store values for use by another program, such as another
FST or a Modbus program, or a PID control loop.
The FST handles all other points in the standard fashion.
11.4

FST Editor

The FST Editor is used to develop FSTs. To open the FST Editor, click
window shown in Figure 11-1 is displayed.
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Utilities > FST Editor
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Micro Motion Model 3711 Gas Flow Computers
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