Coupling Of The Plc Cpu; General; Properties Of The Plc Cpu; Interface With Integrated Plc - Siemens SINUMERIK 840D sl Function Manual

13.8

Coupling of the PLC CPU

13.8.1

General

A CPU of the S7-300 automation system is used as PLC for the SINUMERIK 840D sl. The
PLC-CPU is integrated into the NCU component as a sub-module. A reference to the
performance data of the PLC CPU can be found in Section "Key data of the PLC CPU
(Page 823)".
13.8.2

Properties of the PLC CPU

The PLC integrated in the SINUMERIK 840D sl generally has the same functionality as the
corresponding SIMATIC S7-300 PLC.
For differences, see reference in Section "Key data of the PLC CPU (Page 823)".
Owing to differences in their memory system as compared to a SIMATIC S7-300 PLC, certain
functions are not available (e.g. save blocks on memory card, save project on memory card).
Note
As with the PLC integrated in SINUMERIK, there is no automatic start of the PLC after power
failure and recovery for a SIMATIC S7-300 PLC when a "PLC stop" is triggered by an operator
action on the programming device. For safety reasons, the PLC remains in the stop state with
an appropriate diagnostic entry. You can start the PLC only by an operator action on the
programming device, "Execute a restart", or via the mode selector "Stop" > "Run" (warm
restart).
13.8.3

Interface with integrated PLC

Physical interfaces
With the SINUMERIK 840D sl, the PLC integrated in the NCU offers the option of exchanging
signals between the NCK and PLC directly via a dual-port RAM.
Data exchange with the operator panel
Data exchange with the operator panel (e.g. TCU/OP) can be performed via Ethernet or
PROFIBUS. With a connection via Ethernet, communication takes place via the integrated
communication processor (CP 840D sl).
Data exchange with the machine control panel (MCP) and handheld unit (HHU) can be
performed via MPI, PROFIBUS or Ethernet.
Programming devices should preferably be connected via Ethernet or via MPI (Multi-Point
Interface) directly to the PLC.
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
P3: Basic PLC program for SINUMERIK 840D sl
13.8 Coupling of the PLC CPU
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