OPC UA
OPC UA (OPC Unified Architecture, IEC 62541) is the platform-independent machine-to-machine communication standard for industrial and building automation, providing a unified information model, built-in security and interoperability across BMS, SCADA, and IoT systems. These guides cover the full IEC 62541 architecture, building automation server implementations, and practical gateway configuration for BACnet and Modbus legacy device integration.
OPC UA Architecture: Information Model, Security, Sessions and Transport
IEC 62541 standard covering all 13 parts — platform-independent TCP/IP binary protocol, browsable address space with NodeClass types (Object, Variable, Method, View, DataType), three transport options (opc.tcp://, HTTPS, WebSockets), security modes Sign/Sign+Encrypt with Basic256Sha256 and Aes256Sha256RsaPss policies, X.509 certificate authentication, subscription MonitoredItems with PublishingInterval and SamplingInterval, and OPC UA companion specifications for buildings and I4.0.
OPC UA in Building Automation: BMS Integration, Data Logging and KPIs
Connecting BMS (BACnet, Modbus), energy management (IEC 62056) and CMMS via unified OPC UA interface — Siemens DESIGO CC OPC UA server, Schneider EcoStruxure BMS, Beckhoff TwinCAT OPC UA Server (free), ISO 16739-1 IFC building information model mapping, kWh subscription to energy management platform, OPC UA PubSub MQTT bridge, asyncua Python client example, and certificate-based security hardening.
OPC UA to BACnet and Modbus Gateway: Protocol Translation for BMS Integration
Exposing legacy BACnet/IP and Modbus TCP devices as OPC UA nodes — Kepware KEPServerEX with BACnet/IP driver (BBMD, UDP 47808) and Modbus TCP driver, Cogent DataHub and softing edgeConnector comparison, Holding Register to OPC UA Float Variable DPT mapping, BACnet object to OPC UA node mapping table, VLAN segmentation and certificate auth for gateway security, UaExpert browser testing, and Azure IoT Hub OPC Publisher for cloud telemetry.
Need OPC UA integrated into your building automation system?
We configure OPC UA servers on Siemens DESIGO CC, Beckhoff TwinCAT, and Kepware KEPServerEX — connecting BACnet, Modbus, and KNX subsystems into a unified data layer for SCADA, energy management, and cloud reporting.
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