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Version: 5.2

OPC Links

Sources for errors, which limit the access on local OPC server, are not known yet. However accessing distributed OPC server can be tricky.

Connection can´t be set up – remote only​

The property “OPC-Server” gives out <error browsing opc-servers>.

OPC Classic Transfer Object

Check if the DCOM Configuration is correct:

  • Does the configuration environment run under the same user, who has DCOM access to the OPC server?
  • Are the components OPC Enum and OPC server on the destinated computer cleared for the user?
  • Is DCOM in general activated on the destinated computer?
  • Are the local firewalls shut down on all computers involved?
  • Of course the destinated computer is switched on and accessable!

The OPC server could be linked in the configuration, but the OPC link doesn´t show up within the connection projecting in the OPC transfer object, or an error is given out.

  • You have to save the OPC link with the “OK”button, before you can use it.

Tag browser isn´t able to connect with the OPC server​

As far as the OPC link was configurated without problems, check if the OPC server has just been switched off manually, or has been initialised.

  • Is the computer with the OPC server switched on an accessable?

No data transfer can be done during run time​

The connection could be projected easily during concept time. During run time there is no transfer. Call the log data with the tray icon. Search for the error message at the end of the data. Does it look like this?

16.07.10 14:49:06.194 [Error:OPCConnectionManager] 
   Wasn´t able to  connect<Item\> (E_INVALID_ITEM_NAME)
  • Most likely you´ve written the item name incorrectly, or your OPC server interprets the property Access Path wrong, which is deposited in the OPC link. Choose the item in the tag browser and/or configurate a link without Access Path for testing. Check if your OPC server runs without problems.

Error message in log data:

16.07.10 15:19:34.886 [Error:NoChannel] Timeout connect OPC Server!
  • In distributed systems: Is the computer with the OPC server switched on and accessable?

Error message in log data:

16.07.10 15:16:24.694 [Error:OPCConnectionManager] Wasn´t able to connect to OPC server
   <OPC-Server\> on <IP\>.
  (Message: CoCreateInstanceEx: Access denied)
  • If the connections runs during concept time, most likely the router configuration runs under the right user, but the router service doesn´t. Check if the router service runs under the user, who has DCOM rights on the OPC computer.