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80-1403-01, Rev. 3
HART MENUS AND DATA
Menu data included in the DD file defines
a logical grouping of data and commands. The
grouping uses a “tree” technique, with a root menu
that branches into submenus. The root menu, by
convention, is called “Online.”
HART masters may use techniques other
than the menu tree system to display information.
This instruction manual is based on the menu tree
system included in the DD.
Menus can contain read/write parameters,
read-only parameters, commands, and other
menus.
When writing to a parameter, make certain
the data is transferred to the slave device and not
just recorded in the master. Most masters have a
technique to “send” the data.
When reading a parameter, make certain the
data is up-to-date. The DD provides information to
the master on how often data should be updated,
but the master has the responsibility of actually
updating the data.
Commands typically tell the slave to change
states, and may or may not change parameter
data. For example, a HART command can cause
the DCM-3 to go through a power-up reset cycle,
but that doesn’t necessarily change any parameter
data.
The same parameters can appear on multiple
menus, and the read/write permission can be
different on different menus. The labels used
to display parameters can be used for multiple
purposes. For example, the label Feedback is
used in the Feedback Setup menu to identify if the
Feedback function is enabled, and is used in the
Online menu to identify the current signal.
Some data items only appear in appropriate
circumstances, such as when corresponding
hardware is installed in the field device.
MENU TREE
The menu tree to the right is defined in the
DD for the DCM-3, but the display is master-
dependent. Values shown for various parameters
are hypothetical, actual values will differ. Some of
the parameters shown in the menus are product
configuration dependent; these parameters may
not show in some applications.
A cross reference of parameter label to menu
block can be found on page 46.
Online Menu
(Block 1)
The first line of the Online menu is a link to the
remainder of the menu tree. The other lines are
the values of the process related parameters.
1 Function
: The link to the remainder of the
menu tree.
2 Position
: The output shaft position displayed
as percent of range. The range is selected
with travel and 0% settings. (OUTPUT SHAFT
POSITION SENSING, page 28)
3 Demand
: The Demand signal displayed as
percent of range. The range is selected by 0%
and 100% values. (DEMAND, page 25)
4 Loop(Dem)
: The milliamp signal from the
customer wiring terminals measured at the
DCM-3.
5 Trq/Thrust
: Not active for the Group 14.
6 Temp
: the ambient temperature of the DCM-3.
(TEMPERATURE SENSING, page 22)
7 Feedback
: The milliamp output signal
representing the present position of the output
shaft. (SHAFT POSITION OUTPUT SIGNAL,
page 31)
Function Menu
(Block 2)
This menu allows branching out to the
remainder of the menus.
DCM-3 HART
Menus
