Open Platform Communications (OPC) is a series of standards and specifications for industrial telecommunication. OPC specifies the communication of the real-time plant data between control devices for different developers of SCADA software. OPC was designed to provide a common bridge for Windows-based software applications and process control hardware. The aim was to reduce the amount of duplicated effort required from hardware manufacturers and their software partners.
Tibbo OPC Server supports the most common OPC specification - OPC Data Access (OPC DA), which is used to read and write real-time data. The data source can be any device that supports the Tibbo AggreGate protocol. AggreGate is a white-label IoT integration platform employing modern network technologies to control, configure, monitor and service electronic devices, as well as distributed networks of such electronic devices. It also helps you aggregate device data in the cloud, where you can "slice and dice" it according to your needs, as well as let other enterprise applications transparently access this data through the AggreGate server.
Tibbo OPC server has built-in AggreGate network protocol and can interact with any Tibbo devices by AggreGate agent protocol as well as it can connect to AggreGate server. The AggreGate agent protocol open-source implementation is published for Java, C#, and C++ programming languages, so your connection scheme is not limited to Tibbo devices or AggreGate server only.
The simplest example: TPS reads Tibbit #29 (Ambient temperature meter), sends data to OPC server by AggreGate agent protocol.
A more complex example: you have a Windows-based PC that controls a wood processing machine with the help of AggreGate server by the Modbus protocol. If Tibbo OPC server is connected with AggreGate server, the data from the machine is transmitted to Tibbo OPC server and, as a result, you can monitor and operate the machine via any OPC client (e.g. Matrikon Client).
Tibbo OPC Server sends the OPC Client applications the information on the Value, Quality and Timestamp of an item (tag). These fields are read from the AggreGate variables.
If OPC Server loses communication with their data source (AggreGate Server or AggreGate Agent), the process values are set to Bad [Configuration Error] quality. If the AggreGate variable value is empty, the quality is set to Uncertain [Non-Specific].
Concordance table of the AggreGate variables and the OPC data types are represented in the following chart:
|AggreGate Data Type||OPC Data Type|
|DATATABLE||OPC VT_BSTR (by default)|
It also supports arrays of simple data types listed above (VT_ARRAY).