When addressing the data area of a SIMATIC S7-200 CPU via the OPC Scout, note that you must take into account the OPC server object model when creating a variables link. Access to the variables area is always via the DB1 of the S7-200 CPU. The example below of a variables area in DB1 of the S7-200 CPU explains how to proceed with SIMATIC NET OPC Scout.
The requirement is an existing connection from the OPC server to an S7-200 CPU.
- Start the OPC Scout and double-click on the object "OPC.SimaticNET".
- Add a new group and assign a new group name of your choice.
- Acknowledge the dialog with "OK".
- Right-click the group you have added and select the function "Add Item".
- Select "Connections > S7 > connection name xy".
("connection name xy" represents the name of the connection that you have configured in NetPro. This is a language-specific default name (e.g. "S7-Verbindung_x" [German] or "S7-connection_x" [English]) if you have not changed it in NetPro).
- Using the "-->" button insert an item into the column "The listed Item(s) will be added to Group:...".
- Select the newly inserted item and then right-click on it. Select "Modify Item" from the pop-up menu.
- Now you can edit the item. Delete the right section of the string up to the closed square brackets and replace it with a variables area from DB1 according to the following syntax:
<Data block number = DB1>, <Data type><Byte address in the V memory>, <Number of values of the data type specified>.
Example: DB1, B2, 3 = in this case access to the V memory starts from the second byte as array with 3 bytes.
- Acknowledge the definition of your variables with "Modify Item".
If you do not use the "-->" button to copy the connection name into the right-hand table column, but enter it manually, then make sure that it matches the connection name in the left column and thus the NetPro configuration.
- Click the "OK" button to transfer the link to the data area of the SIMATIC S7-200 CPU into the item list and the item information is displayed.
You can write values to the SIMATIC S7-200 CPU by double-clicking the "Value" field of the item concerned and entering a value.
If you cannot open the S7 window under "Connections", then an S7 connection has not be configured.