Fig. 4: I/O modules (S500-eCo) connected to an AC500-eCo processor module via Modbus/TCP network, using a
Modbus/TCP communication interface module or a processor module as client.
3.4 AC500/S500: Short description hardware
AC500 processor modules contain the CPU with the core component of the PLC. The CPU is
connected with the user memory, input and output module, communication port and other units
via the system bus and performs tasks by means of system programs preset in the system
memory. The CPU adopts the function preset by the application program to command the PLC
for operation.
It has the following functions:
● To receive user programs and data entered
● To diagnose work faults of the power supply and PLC circuit as well as syntax errors in
programming
● To receive the state or data of the site via the input interface and save it into the shadow
register or data register
● To read the user programs in the memory one by one and execute them after interpretation
● To updating the state of the associated flag bits and the contents of the shadow register
according to the execution results and providing output control using the output unit.
Processor modules are available in different performance classes. Only one processor module
is required for a valid system architecture.
There are different types of processor module available that differ in the features and functions
they provide, e.g. performance, LED display etc.
If required, processor modules are also available with an integrated Ethernet communication
module (TCP/IP).
Processor
modules
Communication
modules
System overview
AC500/S500: Short description hardware
2023/03/03
3ADR011074, 1, en_US
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