Direct outstations use permanent communications, such as a cable, radio or network, to communicate with the ClearSCADA server. Within the ClearSCADA database, you configure Direct outstations in sets that use Direct Channels for communicating with the server.
Direct outstations can belong to Direct Outstation Sets or Switched Outstation Sets, depending on the communications set-up that is required. Depending on the functionality supported by the driver and outstation type, direct outstations can be configured to use these communication set-ups:
On most systems, ClearSCADA is configured to instigate communications with any direct outstations whenever required. On some systems, the communications availability might be restricted on some direct outstations. For example, communications might be limited to Incoming Only (whereby the outstation instigates all communications with ClearSCADA), or Periodic (whereby communications with the outstation is only available for a limited period). For more information, see Specify the Availability of Communications Between the Outstation and ClearSCADA.