An OPC Driver is a module responsible for collecting data from external devices through an OPC Server, which can be developed by any company with knowledge on network and protocols used by a certain device. OPC Tags can be imported to an OPC Driver in E3 (an OPC Driver in E3 works as an OPC client), or they can also be created in E3. In this case, users must know the ItemId of each Tag.
Available objects on an OPC Server
Object |
Description |
|---|---|
OPC Folder |
Defines groups or sub-directories for organizing variables |
OPC Group |
Groups a series of OPC Tags that share the same update parameters (scan time and dead band). An OPC Group must exist to create OPC Tags |
OPC Tag |
Object for reading or writing values to a device. A Tag reading is performed automatically by an OPC Server, with a scan time defined in the OPC Group where it is inserted |
OPC Block |
Allows writing or reading a set of values. To perform a writing, users only need to attribute a new value to the Value property |
OPC Block Element |
Allows reading or writing one of the Elements of an OPC Block where it is inserted. An OPC Block reads a data table and this object is always linked to a position defined by its Index property, corresponding to a monitored variable |
