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Entry type: FAQ Entry ID: 88737127, Entry date: 03/26/2014

PN/PN Coupler Getting Started

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PN/PN Coupler Getting Started

  1. Overview of PN/PN coupler module
    PN/PN Coupler is used to connect 2 PROFINET networks for data exchange, and it may input and output as many as 256 bytes. It is equipped with 2 PROFINET ports, and each port works as an IO Device to be connected to its own PROFINET system. The actual appearance of the product is as shown in Fig. 1, and its typical usage mode is as shown in Fig. 2.

    Fig. 1: Product appearance of PN/PN Coupler

    PROFINET IO network 1 status light of PROFINET IO network 1
    PROFINET IO network 2 status light of PROFINET IO network 2
    Power connection 1 and indicator lamp MAC address of PROFINET IO network 1
    Power connection 2 and indicator lamp MAC address of PROFINET IO network 2
    diagnosis indicator lamps of PROFINET IO network 1 and 2 MMC card slot

    Fig. 2: Usage method of PN/PN Coupler

    In Fig. 2, 2 S7-300 modules work as IO Controllers to communicate with ET200S and PG/OP through PROFINET to form 2 PROFINET systems. At the same time, the 2 S7-300 modules shall also conduct real-time data exchange, and PN/PN Coupler may be used to deliver data at this moment.
    The 2 PROFINET networks coupled with PN/PN Coupler are independent of each other, and their communication rates may be different. Each PROFINET port may work as an independent IO Device and have independent Device name, and the two PROFINET port may have different Update time. However, the communication data areas of these 2 networks must correspond to each other in input/output mode, as shown in Fig. 3.

    Fig. 3: Data corresponding mode of PN/PN Coupler

    The PN/PN Coupler shown in Fig. 3 has its Device name as "Coupler-X1" in PROFINET network 1, and it is configured with 16-byte output data and 8-byte input data. Correspondingly, it has 16-byte input data and 8-byte output data in PROFINET network 2. The Device name of PN/PN Coupler is "Coupler-X2" in PROFINET network 2.
  2. Configuration and debugging of PN/PN Coupler
    One example is given here to describe the configuration process of PN/PN Coupler in STEP7.
    2.1 Data communication area assignment in the example
    PROFINET network X1:
    PN/PN Coupler's Device name is “Coupler-X1”, its IP address is,and its Update time is 2ms.
    Data communication interface area with network X2:
    .1-byte input
    .6-byte input/ 12-byte output
    .2-byte output
    PROFINET network X2:
    PN/PN Coupler's Device name is “Coupler-X2”, its IP address is,and its Update time is 8ms.
    Data communication interface area with network 1:
    .1-byte output
    .12-byte input/ 6-byte output
    .2-byte input
    2.2 Configuration process of PN/PN Coupler in PROFINET network 1
    Open STEP7, and create a new project named as "PN_PN Coupler". Insert one S7-300 station in the project, and after completing hardware configuration, insert one PROFINET network to create PROFINET IO system. In the right-side hardware catalog, drag the corresponding PN/PN Coupler under PROFINET-IO-System, as shown in Fig. 4 below:

    Fig. 4: Drag in PN/PN Coupler

    Notes: There are multiple PN/PN Couplers in the hardware catalog, and they must corresponding to each other in configuration. If the current S7-300 connects PROFINET X1 port of PN/PN Coupler, it shall select PN/PN Coupler X1 configuration, or an error will be reported. Similarly, as some IO Controllers do not support extended diagnosis function, migration method shall be selected in configuration, as shown in Fig. 5. For more information about extended diagnosis, please refer to the webpage below:

    Fig. 5: Configure PN/PN Coupler in migration mode

    Then double-click PN/PN Coupler in the network, and set Device name and IP address in the popup properties dialog box.

    Fig. 6: Set Device name and IP

    Then double-click X1 slot in the PN/PN Coupler configuration, and set Update time in the popup properties page.

    Fig. 7: Set Update time

    Next, configure input/output data in the related slot of PN/PN Coupler, as shown in Fig. 8.

    Fig. 8: Configuration data area

    After configuration completes, compile and save the project. Then assign Device name. Select PN/PN Coupler in the hardware configuration, click PLC menu-> Ethernet, and select Assign Device Name, as shown in the Fig. below:

    Fig. 9: Assign Device name.

    Fig. 10: Assign Device name.

    After selecting Assign Device Name, STEP7 may automatically scan the nodes in the network and list all node-related information. After verifying that MAC address is consistent to that on PN/PN Coupler, click Assign name button to assign Device name, as shown in Fig. 10.
    Note: when assigning Device name for PROFINET X1 network of PN/PN Coupler, the computer shall access PROFINET X1 network, and at the same time, the MAC address of X1 network on the module shall be checked. Similarly, the computer shall access X2 network when assigning device name for X2 network.
    2.3 PN/PN Coupler configuration process in PROFINET network 2
    Insert another S7-300 station under a same project. PN/PN Coupler hardware configuration process is similar to the Device name assignment process, but it may be configured in the communication data area in a simpler method. After setting Device name, IP address and Update time, double-click PN/PN Coupler directly, and in the properties dialog box select PN/PN Couple directly in PROFINET network 1, as shown in Fig. 11 below. Then the communication data area may be matched automatically.

    Fig. 11: Select corresponding PN/PN Coupler

    If they are not in a same STEP7 project, the communication data area of PN/PN Coupler shall be configured according to the matching relationship. The data areas of both sides are configured as in Fig. 12 below:

    Fig. 12: Data matching

    2.4 Communication test
    After compiling and saving all projects, download them into CPU, and create a Variable table. Assign input and output values by force, and check the data status.

    Fig. 13: Data exchange status

    For more information for PN/PN Coupler, please refer to "PN/PN Coupler installation and operation manual". The download address is shown below:

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