Callback (PSTN)

Associated with: WITS Outstations (with PSTN)

Security permission required to access this pick action: Diagnostics

ClearSCADA has a Callback (PSTN) action that you can use to test a WITS Field Device's ability to initiate a PSTN connection with ClearSCADA. While Callback (PSTN) works in a similar way to Callback on other drivers, the WITS driver requires you to specify a Device Port and Telephone Number.

You can use the Callback (PSTN) action if:

• Your WITS Field Device supports PSTN Callback
• Callback is enabled on the PSTN tab of the Outstation Form
• Your ClearSCADA user account has permission to access the Callback (PSTN) action.

To instruct a WITS Field Device to initiate a PSTN connection with ClearSCADA (for testing purposes):

1. Log on to ViewX via a User Account that has the Diagnostic permission,
2. In the Database Bar, right-click on the WITS Outstation item that represents the Field Device you want to test.
3. Select Callback (PSTN) .

4. Enter the parameters for the connection you want to test. These are:

   • Device Port—The port on the Field Device that is used for the connection to ClearSCADA. Typically, the Device Port setting is used to define which modem is used (for Field Device's that have multiple modems).
   • Telephone Number—The telephone number for connecting into ClearSCADA. You can select the appropriate telephone number from the combo box (ClearSCADA enumerates the suitable DNP3 PSTN Channels and builds a list of their phone numbers). Alternatively, you can enter the number manually.
5. Select OK.

If the parameters are correct, ClearSCADA will make a Callback request. The way in which the Callback request is made will vary, depending on the Callback setting for the WITS Outstation (PSTN tab). For more details on the Callback setting, see Define an Outstation's PSTN Properties in the ClearSCADA Guide to Advanced Drivers.

If the Callback succeeds, an event is logged. The message of the event indicates that the Callback succeeded. You can view the event in the Events List (see Display the Events List for an Item or Group in the ClearSCADA Guide to Lists).

ClearSCADA will wait for a specified amount of time for a Callback to take place (see Define the WITS Callback Time Period). If the Callback does not occur during this time, ClearSCADA deems the Callback to have failed and generates an alarm.

You can view any Callback-related alarms in the Alarm Banner, Alarms List, and on other alarms displays. For details on how to access these displays, see:

• Display the Alarms List for an Item or Group in the ClearSCADA Guide to Alarms.
• Display the Alarm Banner in the ClearSCADA Guide to Alarms.