Siemens Industry Online Support
Siemens AG
Entry type: FAQ, Entry ID: 19295355, Entry date: 08/18/2005

What are the options for connecting a PG/PC online to the S7 controller via Ethernet?

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When setting up an online connection between a PG/PC and an S7 controller via Industrial Ethernet, you must observe a number of aspects.

First, you must insert a PG/PC in NetPro, which is to represent the logical interface of your PG/PC to the Ethernet system bus.

Fig. 01

In the Properties dialog you connect the PG/PC via the Ethernet interface to the Ethernet system bus and assign a unique IP address for the PG/PC in the network.

The IP addresses of the PG/PC and the S7 controllers in NetPro must be in the same IP address range!

Fig. 02

The IP address set in the Microsoft Windows Control Panel must not be the same as the IP address configured in NetPro.

Please note the following three points when assigning the Windows IP address:

  1. In the Windows settings (Start > Control Panel > Network Connections > Properties > Internet Protocol (TCP/IP > Properties)) of the PG/PC the IP address set is the same or one in the same subnetwork.

    Fig. 03

    Possible IP addresses for the PG/PC:
    S7 controller PG/PC -

    Fig. 04
  2. The Windows IP address  (Start > Control Panel > Network Connections > Properties > Internet Protocol (TCP/IP > Properties)) of the PG/PC is in a different subnetwork to the IP address configured in NetPro.

    Fig. 05

    In this case an online connection between the controller and the PG/PC can only be made via an IP Router. The IP Router can communicate data packages between different IP subnetworks and a routing table. The IP address and the subnetwork mask of the controller and of the PG/PC must be entered in the routing table in order to be able to set up the online connection.

    Fig. 06

  3. The Windows IP address will be referenced automatically via a DHCP server.

    Fig. 07

    The IP address can also be referenced automatically via DHCP if the IP addressed assigned already meets the conditions given in Points 1 and 2.

Using the Ping command you can test whether an Ethernet connection can be set up between the PG/PC and the S7 controller or the CP343-1/CP443-1.

No. Procedure
1 Open an MSDOS prompt ("Start > Run > cmd").
2 Enter the "ping" command and the IP address of the S7 controller - e.g. "ping".
3 The S7 controller is then accessible via Industrial Ethernet when reply messages are sent in response to the ping request.

Fig. 08

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