OPC Data Access is a group of client–server standards that provides specifications for communicating real-time data from data acquisition devices such as PLCs to display and interface devices like Human–Machine Interfaces (HMI), SCADA systems [2] …

2024年4月12日 · OPC DA (Data Access) is a protocol standard introduced earliest by the OPC Foundation, mainly used for accessing and exchanging real-time data. It is built on Microsoft's COM/DCOM technology, providing an industrial automation system with a standardized communication interface.

2021年9月14日 · OPC is the one universally accepted standard for exchanging data between different industrial automation systems. How does OPC DA work? The following diagram shows a typical OPC DA configuration.

2019年8月6日 · OPC UA is not only for OPC-DA, but for all OPC Classic (DA, AE, HDA, etc). OPC Classic uses DCOM communication for Client-Server connection. DCOM is for Windows OS.

You may have also heard about OPC XML-DA, OPC Security, OPC commands, & OPC batch. All of these were standards to address specific types of problems, but none were as widely adopted as OPC DA, A&E, and HDA. As a collection, these …

OPC DA allows to access only the current data and is incapable to generate alarms, historical events whereas OPC UA supports features like historical events, multiple hierarchies and provides methods and programs (that are called commands).

2021年6月4日 · OPC DA (Data Access) is the most common standard which describes a set of functions for real-time data exchange with PLC, DCS, HMI, CNC and other devices. OPC HDA (Historical Data Access) provides access to already saved data and history.

Title: Data Access Description: The original OPC Specification and its evolution from versions 1, 2.x, and 3.0, covering: The concepts of OPC Client/Server technology and data definition

OPC DA stands for OPC Data Access. It is an OPC Foundation specification that defines how real-time data can be transferred between a data source and a data sink (for example: a PLC and an HMI) without either of them having to know each other’s native protocol.

What is OPC DA? Used to move real-time data from PLCs, DCSs, and other control devices to HMIs and other display clients. While DA3.0 is the current specification, most OPC servers use the previous specification, 2.05a. The earliest version is 1.0.