An M580 system can provide an embedded OPC UA server through the supported server hardware and software. A SCADA, EcoStruxure application or historian can browse exposed variables by name and subscribe to their values. This simulation lets you browse the address space and inspect subscription updates. It also shows how the configured security policy and certificate trust affect whether a client can establish the connection.
The left side represents the M580 system's OPC UA address space. Select a node to inspect its NodeId, data type and live value. On the right, a client (think EcoStruxure or a SCADA) holds a subscription for three nodes. Change a process value and inspect the notification displayed by the client. Then change the security policy to compare the accepted and refused connections in this example.
| Monitored item | Value | Source timestamp |
|---|
Set the policy to Basic256Sha256 with an untrusted client certificate. In this configuration, the connection is refused with BadSecurityChecksFailed and the subscription cannot start. The selected policy requires certificate trust before data exchange. A subscription can deliver changes at the configured publishing interval, but the traffic depends on update rates and settings. A screen with 500 tags still needs its communication load and timing checked.
🌳 Address space & NodeId. The address space contains nodes and references for objects, variables and methods. Each node has a NodeId and variables expose a data type. Browsing helps a client find the available data; the server configuration determines which nodes it can access.
🔔 Subscriptions & monitored items. A client selects monitored values and configures a publishing interval with the relevant monitoring settings. Notifications report qualifying changes. Inspect the source timestamp and quality information along with the value rather than assuming that an unchanged display is current and valid.
🔐 Security built in. The example compares security policies (None → Basic256Sha256), certificate trust, message signing & encryption, and user access choices (anonymous / user+password). Select and configure the security required by the installation; the protocol's available mechanisms do not secure an endpoint automatically.
☁️ Vendor-neutral to the edge. A compatible OPC UA client can use the exposed data in a Schneider SCADA, EcoStruxure application or historian. The M580 system's server and the receiving application must support the required data, security and connection settings.
For an M580 system, first identify the OPC UA server implementation and its configuration requirements. Select the variables to expose, configure the endpoint and security policy, and establish the required certificate trust. The commissioning steps depend on the server hardware and software; they are not a universal CPU setting in Control Expert.
A SCADA needs 500 M580 tags on screen, most of them rarely changing. Why is an OPC UA subscription useful compared with repeated individual read requests?