Chapter 4. Toolchest Components
14
PACSystems* RX3i Genius Dual Bus Application Guide
GFK-2928
4.2
Adding Dual Bus Logic
In the ladder block named
_Main
, insert a new row at the beginning of the program.
While holding down the
Ctrl-key
, drag the program block named
BUSSES
and place it into the first rung. This
will create a new instance of the block. It will require a name: enter
GBusses
for the name.
Zoom into the ladder block named
BUSSES
. Note that the program block already contains multiple rungs of
logic. Program blocks in these rungs perform the following:
INIT_GB00
This structured text block defines the parameters for a dual bus (the instance is named
IGB00
for “
I
nitialize
G
enius
B
us
00
”
). The block must be edited to match the specific design
characteristics of the system.
DBUS
This ladder block maps the discrete and analog inputs for the dual bus (the instance is
named
DB00
). It does not require additional editing.
AUTO_SW
This ladder block provides a simple automatic role switching method (the instance is named
Aut_Sw
). It does not require additional editing, but you may wish to modify or enhance the
PLC failover operation.
The logic at this point is sufficient to service one pair of dual busses. If there are more dual busses, then
additional rungs will be required.
