SC Series Controllers
Embedded PLC
9
Embedded PLC
Each SC Controller has an internal software PLC. This PLC serves to enhance the integration of the SC
controller into an end user's plant. The PLC emulates features of industry standard PLC controllers, using many
of the same layouts, addressing structures and commands. Alpha Toolbox has a PLC editor but RSLogix500
can also be used to program ladder logic for the embedded PLC.
9.1
Rack layout
The SC controller's PLC has a 4-slot virtual rack layout. The virtual rack is filled as follows:
24 DC I/O
19-Pin Connector
I
N
P
U
T
S
Standard
Slot #0
The 24V DC I/O Module in slot 0 reflects the physical I/O on the SC controller.
The Trailing Fieldbus card in slot #2 uses the M-12 DeviceNet connector on the bottom of the controller when
the DeviceNet option is ordered. The DB-9 connector is used when Profibus is ordered. The RJ-45 jacks are
used when Ethernet/IP or Profinet are ordered.
The ModbusTCP card in slot #1 comes installed as standard equipment on SC3-SC6 controllers. Each uses the
RJ-45 ETHERNET jack on the bottom of the SC controller.
9.1.1
Addressing scheme
Use the following syntax when programming to reference any input or output: Type: Slot#. Word/Bit Type can be
Input I or Output O.
For example, if a switch was wired to Pin L, a light was wired to Pin C and logic was required to turn on the light
when the switch was activated, the logic and addressing would look like this:
102 / 1032
Modbus TCP
Network Ehternet Port
O
I
U
N
T
P
&
P
U
U
T
T
S
S
Ethernet/IP or PROFINET
O
I
U
N
T
P
&
P
U
U
T
T
S
Standard
S
Slot #1
Fieldbus
DeviceNet, Profibus,
O
U
T
&
P
U
T
Optional
S
Slot #2