Siemens SINUMERIK 840D sl Manual page 37

Introduction
This manual describes the structure and commissioning of the system network with
SINUMERIK solution line control and operator components with Ethernet-based
communication. The fundamentals of the system network are described first, details and
special cases are described in subsequent chapters.
Fundamentals
The system network for SINUMERIK solution line is structured as a star topology with a central
Ethernet switch, to which all Ethernet-based components of the system are connected.
For an NCU the connection is executed via the X120 Ethernet socket, for PCU it is executed
via the "Ethernet 2" connection. There is no default for all other components with two Ethernet
connections. These components have an internal 2-port switch and may be used to connect
an additional operator component. Thus in this case there can be deviation from the strict star
topology.
System network
In the system network the IP address 192.168.214.xxx with subnet mask 255.255.255.0 is pre-
selected. Here there is precisely one DHCP server with DNS that can run on one NCU or one
PCU. The server ensures assignment of IP addresses to the Ethernet components in the
system network (DHCP clients) from a specified address band.
The following rules apply for assignment of IP addresses in the system network:
● For all NCUs and PCUs the commissioning engineer assigns fixed IP addresses in the
associated address bands, as well as appropriate computer names (host names). All other
(operator) components are automatically assigned an IP address from the DHCP server.
Its name is generated automatically (for MCP, MPP, HT 8), or is entered at commissioning
(TCU).
● If there are multiple NCU and/or PCU in the system network the system automatically
(depending on the start-up sequence) specifies the DHCP server and automatically ensures
synchronization of all necessary data so that the next time the system boots any other NCU
or PCU could take on the role of DHCP server. However it is a good idea to specify a DHCP
master. This is an NCU or PCU in the system network that is available at each system boot
and which regularly takes over the task of the DHCP server and DNS server.
Synchronization of data takes place in any event so that any other NCU or PCU can take
over this task. All non-master NCU / PCU wait in the system boot an adjustable length of
time for availability of the master.
Note
In a system network, on a boot server respectively - i.e. the NCU or PCU which
accommodates the active DHCP server - a maximum of 30 operator stations may be
operated simultaneously with a TCU.
A maximum of 10 operator stations with a TCU may connect up simultaneously with the
same HMI application when powering up.
Operator panel front: OP 012
Manual, 09/2016, A5E36371591B
General information and networking
1.4 Networking
37