---
description: Overview of the OPC UA Standard machine-integration contract, its documentation map, and supported capabilities.
alias: userguide-equipment-integration-opcua-standard
---

# OPC UA Standard

## Overview

The **OPC UA Standard** is the reusable machine-integration contract delivered with the **Industrial Equipment Template**. A physical machine is represented by a **Critical Manufacturing MES Resource** and exchanges operations, recipes, process data, and state through **Connect IoT**.

This documentation covers the complete implementation lifecycle: modeling, setup, machine-interface implementation, runtime behavior and commissioning considerations.

## Documentation Map

```mermaid
flowchart LR
    M("1. Model<br/>MES Resource Hierarchy") -->
    S("2. Set Up<br/>MES and Connect IoT") -->
    C("3. Configure<br/>Settings and Features") -->
    I("4. Implement<br/>Machine OPC UA Nodes") -->
    V("5. Validate<br/>Commission the Integration") -->
    O("6. Operate<br/>Monitor and Troubleshoot")

    classDef standard fill:#FFFFFF,stroke:#64748B,color:#334155,stroke-width:1.5px;
    classDef secondary fill:#FFFFFF,stroke:#CBD5E1,color:#64748B,stroke-width:1.5px;
    classDef highlight fill:#075C00,stroke:#075C00,color:#FFFFFF,stroke-width:1.5px;

    class M,S,C,I,V,O standard;

    linkStyle default stroke:#94A3B8,stroke-width:1.5px;
```

| Area                                                                                                                                                                           | Use it to                                                                                                                                                      |
| ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [Modeling and Design](modeling/index.md)                        | Understand the architecture, responsibilities, MES Resource model, ISA-95-aligned identity, OPC UA address space, end-to-end process, and integration patterns |
| [Setup and Configuration](configuration/index.md)               | Prepare MES and Connect IoT, configure OPC UA connection profiles, Resource and Parameter settings, feature contexts, and state mappings                       |
| [Features](features/index.md)                                   | Implement each operation, Recipe, Data Collection, and State feature step by step, and consult the node contract                                               |
| [Commissioning and Support](commissioning-and-support/index.md) | Validate production readiness, troubleshoot connection and runtime behavior, and identify the relevant project artifacts                                       |

!!! note "Ready-to-use example"
    The [Sample Master Data](../../modellingguides/samplemasterdata.md#opc-ua-standard-integration-example) includes an **OPC UA Standard Integration Example** that models this integration for the **MAIN BOARD** Resource, so the standard can be explored without building the master data from scratch.

## Supported Capabilities

| Capability                | Business result                                            | OPC UA area          |
| ------------------------- | ---------------------------------------------------------- | -------------------- |
| **Track In**              | Starts Material processing at a Resource                   | `Operation.TrackIn`  |
| **Recipe Download**       | Sends the resolved MES recipe values to the machine        | `Recipe`             |
| **Data Collection**       | Stores process readings in an MES Data Collection Instance | `DataCollection`     |
| **Track Out**             | Completes Material processing at a Resource                | `Operation.TrackOut` |
| **Abort**                 | Terminates processing exceptionally                        | `Operation.Abort`    |
| **State Synchronization** | Aligns the MES Resource state with the machine state       | `State`              |

## Initiation Modes

- **Machine initiated:** Machine → Connect IoT → MES operation → standard result handshake.
- **Operator initiated:** Operator → MES UI → MES operation → standard result handshake.
- **Hybrid:** either initiation path is accepted, with duplicate-operation protection.

Both paths execute the MES operation within its transaction and then enter the same result handshake. **Connect IoT** writes `MESOperationPerformed`, the machine acknowledges with `MachineOperationConfirmed`, and MES commits the transaction only after that confirmation. If the confirmation is not received within `MachineReplyTimeout`, the operation fails and the transaction rolls back.

!!! info "Scope"
    The standard defines the MES integration boundary. It does not replace PLC sequencing, safety logic, motion control, machine interlocks, or the machine supplier's internal recipe implementation.

## Design Foundation

The Resource base node follows the relevant **ISA-95 equipment hierarchy**. Below that Resource, the **Critical Manufacturing MES Common Data Model (CDM)** organizes MES process information into `Operation`, `Recipe`, `DataCollection`, and `State`. The Boolean handshake nodes are added as implementation control nodes.

## Related Critical Manufacturing Documentation

- [Connect IoT concepts](https://help.criticalmanufacturing.com/tutorials/modules/connect-iot-equipment-integration/connectiot/connect-iot/).
- [Connect IoT administration](https://help.criticalmanufacturing.com/operationguide/application-administration/connect-iot/connectiotadministration/).
- Configure automation scenarios in the Automation step of the Resource creation or editing wizard.