OPC-UA Writer
Write a value to a PLC node via OPC-UA protocol.
The OPC-UA Writer module writes a value from the pipeline data registry to a PLC node. This is commonly used to send inspection results (pass/fail), compliance scores or other calculated values back to the PLC.
Configuration
| Field | Type | Description |
|---|---|---|
| plc_name | string |
The label of the PLC connection (configured on the Devices → PLC page) |
| plc_node | string |
The OPC UA node address, entered manually or selected with Browse |
| value | string |
The data registry key whose value should be written (e.g., anomaly_0.pred_score) |
The value field is not a literal value — it is a reference to a key in the data registry. The module reads the actual value from the registry at runtime and writes it to the PLC.
Behavior
- Reads the referenced value from the data registry.
- Connects to the specified PLC.
- Writes the value to the specified node.
Inputs & Outputs
| Direction | Key | Type | Description |
|---|---|---|---|
| Input | <value> (registry key reference) |
varies | The value to write, read from the registry |
| Output | — | — | No data output (only execution time is recorded) |
Configure the PLC connection first. Browse requires the selected PLC to be reachable; an invalid or unavailable node produces an execution error.