On a Geo SCADA Expert system, you configure the Geo SCADA Expert database so that entries in the database reference the items on the OPC servers that you want Geo SCADA Expert to monitor. You organize database Items into OPC Groups based on how data is to be retrieved. This section summarizes the database items that you need to configure in order for Geo SCADA Expert to read and write to data on other servers, using the OPC protocol.
In order to communicate with other servers using the OPC protocol, the Advanced OPC Driver has to be installed and running on the Geo SCADA Expert servers on your system. The driver is represented by the OPC Client - Advanced component in the Geo SCADA Expert Installation Wizard’s Setup window. The component is located within the Server branch of the tree that is displayed in the window (see Install a Driver in Geo SCADA Expert).
When you configure Advanced OPC items in the Geo SCADA Expert database, many of the settings for those items need to correspond to the settings on the relevant OPC servers on your system. You need to have access to, or a list of, these settings before you can configure the OPC database items successfully.
For instance, you need to know the read and write mechanisms that are supported by the OPC servers on your system, and the user names and passwords that allow the required level of access to the data on those servers.
You also need to be aware of which optional features are required for each OPC item. These features include:
- Alarm views
- Alarm redirections
- Historic data storage
- User methods.
You can also use core Geo SCADA Expert features with Advanced OPC database items, including Lists, Actions, and Mimics. See the Core Documentation for details.
For each OPC server with which Geo SCADA Expert is to communicate using the Advanced OPC driver, you need to configure:
- An Advanced OPC Server to represent an OPC server from which Geo SCADA Expert is to read data.
Any access and security settings required to communicate with that server.
You need to configure one Advanced OPC Server item in the database for each OPC server with which you want to communicate using the OPC protocol, (see Configure the Advanced OPC Server).
- Advanced OPC Group(s) to specify the rates at which the data is to be retrieved from an OPC Server.
You need to configure a minimum of one Advanced OPC Group per Advanced OPC Server. You can attach multiple Advanced OPC Groups to the same OPC server. For instance, you might configure different Advanced OPC Groups to have different rates or offsets, in order to retrieve some data at different intervals or times to other data.
For more information, (see Configure an Advanced OPC Group).
- Advanced OPC Points of the appropriate type to represent the items in the OPC server, such as measuring instruments and control devices.
For more information, see Points Used on Advanced OPC Groups.
To minimize the time that it takes to configure the required OPC items, you may want to configure them in the order listed above, as the group configuration requires that you specify a server, and point configuration requires that you specify a group, and so on.