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Version: 8.1

Connections - OPC Connections

OPC Connections

The OPC Connections page displays all currently configured OPC (both UA and DA) connections.


If you are using an OPC UA connection, you should be using the OPC UA Module. If you are using the DA connection, you should be using the OPC COM Module.

Gateway Webpage - OPC Connections Section

OPC Connections Page

Here on the main OPC Connections page, we can see a list of all current OPC connections, as well as their status. If any are faulted, you can click the red faulted status to get an error message popup with a full description of the error.

Connected ServersDisplays the list of OPC servers out of configured servers, and their status.
NameOPC server name.
FilterSearch criteria to filter for specific server names.
TypeOPC server type - UA or DA
UptimeTotal time OPC server is connected.
StatusCurrent status of OPC server.
DiagnosticsDisplays diagnostic information for any connected OPC UA server.
  • Server - Shows server diagnostics.
  • Client - Shows client connection subscription diagnostics.

OPC Connections Page


Click the Server button to get information on the server. By default, diagnostics are set to off since they can generate a considerable amount of network overhead and impact performance. To turn on diagnostics, click Enable Diagnostics. Not all OPC UA servers support diagnostics.

OPC Connections Page - Server


By clicking on the Client button, it brings up the subscription information for that particular server. It will list out all of the subscriptions to that server with the publishing rates, as well as the number of items within that subscription.

FilterSearch criteria to filter for specific subscriptions.
RefreshRefreshes subscription data.
NameDisplays the subscription name.
RateThe rate defined in the Tag Group, used as the requested sampling interval for monitored Items belonging to the corresponding subscription.
Request Publishing IntervalThe rate a subscription will report accumulated change notifications at. The interval is derived from Rate, unless explicitly defined.
Revised Publishing IntervalThe server's revised rate for accumulated change notifications.
Tag CountThe number of Tags currently subscribed to that Tag Group.

OPC Connections Page - Clients


Clicking the Nodes button for one of the subscriptions will bring up the list of subscribed OPC items.

FilterSearch criteria to filter for a specific node.
RefreshRefreshes node data.
Node IDThe OPC item path.
Requested Sampling IntervalThe rate the underlying tag/node will be polled at.
Revised Sampling IntervalThe revised rate at which the underlying tag/node will be polled at.
Requested Queue SizeDetermines how many data points can be stored and transferred to the client once the sampling rate elapses when the sampling rate is slower that the publishing rate.
Status CodeStatus of the node.

Gateway Webpage Status Nodes