Establishing or changing an online connection - TIA Portal

To use the online functions of a device, specify the connection path the first time you establish the connection.

Requirement

At least one PG/PC interface is installed and is physically connected to a device, for example, with an Ethernet cable. As an alternative, it is also possible to establish virtual online connections using PLCSIM.

Procedure

To establish or change an online connection, follow these steps:

1. Select one or more devices for the online connection in the project tree.

2. Select the "Go online" command in the "Online" menu.

   • If the device has already been connected online, the online connection is automatically established using the previously specified connection path.

   • If there was no previous connection or if the device address is not located in the same subnet of the programming device/PC, the "Go online" dialog opens.

   If you want to change a specified connection path, select the "Extended go online" command instead in the "Online" menu. The "Go online" dialog box is opened again in this case.

3. Select the connection path:

   • Select the type of interface from the "Type of the PG/PC interface" drop-down list.

   • Select the interface of your programming device/PC from the "PG/PC interface" drop-down list.

     No selection is necessary if you have already defined a programming device/PC interface in the settings.

   • Select the interface or the subnet for the connection from the "Connection to interface/subnet" drop-down list. Select a direct connection if no S7 gateway is connected in between. Select the matching subnet for the connection to the programming device or PC if the device can be accessed via an S7 gateway. Select the item "Try all interfaces" if the device has several interfaces and you do not know by which of the interfaces the device is connected to the programming device/PC.

     If you selected an MPI or PROFIBUS subnet, the bus parameters configured in the programming device/PC interface are applied at this point.

   • If the device is accessible via a gateway, select the gateway that connects the two subnets involved in the "1st gateway" drop-down list.

4. Optional: If no devices can be accessed by the selected connection path, a dashed connecting line is displayed between the programming device/PC and the device. This is the case, for example, when the device is connected with the network by a NAT router.

   To display all devices that are switched on and connected to an interface of the programming device/PC, select the entry "Show accessible devices" from the drop-down list and click "Start search" again.

5. Optional: You have two options to access the device despite a different subnet: Use the two options in administered networks only after consultation with the administrator.

   • Assign a static address to the programming device/PC interface under Windows.

   • During the creation of the online connection, an additional IP address in the same subnet as the device is temporarily assigned to the interface of the programming device/PC. Click "Go online" and confirm the next prompt.

6. Click the "Start search" button.

   Devices which can be reached by the set connection path are displayed in the table of the target devices. The connection line in the graphic on the left is displayed as solid.

7. Optional: Run a flash test. Select the "Flash LED" check box on the left in the graphic. You use the flash test to check that you have selected the correct device. The flash test is not supported by all devices.

8. Select the target device in the table and confirm the selection with "Go online".

   The online connection to the selected target device is established.

Result

After the online connection has been established, the title bars of the editors change to orange. An orange progress bar is also shown in the title bar of an editor and in the status bar. In the project tree, status symbols show the difference between online and offline objects.

The set connection path is stored for future connection attempts.

With automatic assignment of the programming device/PC address the dialog reappears when the computer is restarted. The connection must be re-established in this case.

Note Undoing actions You cannot undo actions once you have established an online connection.

Note Using direct connections or subnets An online connection between programming device/PC and connected devices is possible either via direct connection or via subnet. Simultaneous connection of the devices over different subnets is not possible if these are physically connected through the same interface. Simultaneous connections to different subnets are only possible through routed connections. Simultaneous connection of devices through a subnet and through direct connections using the same interface is not possible.