Controlling SAC Startup

iFIX lets you control the startup status of SAC using the task configuration of the SCU.

Starting SAC Automatically

When you enable the SCADA function, the SCU includes WSACTASK.EXE in the startup list within the Task Configuration dialog box. This starts SAC automatically.

If you disable SAC during development, you must enable it again. You can also modify how SAC operates by entering specific command line parameters. The following command line parameters are available:

• S – Synchronizes SAC to the system clock. Refer to the Building a SCADA System manual for information on scan times and synchronization.
• Dseconds – Delays SAC processing of the database until the I/O driver initializes and receives data from control devices. By default, SAC automatically delays processing for 8 seconds. You can use the D parameter to specify a delay of 1 to 300 seconds, for example D30, to control initial processing of database blocks.
• Q – Sets the number of queue entries for the Alarm Queue Status program that monitors the alarms deleted by SAC. This parameter lets you override the default (500), and prevents the queue from expanding to the maximum length of 2000.
• R – Suppresses Range (RANGE) alarms.
• UN – Suppresses Under Range (UNDER) alarms.
• N – Suppresses No Data (NO_DATA) alarms.
• C – Suppresses communication (COMM) and No Data (NODATA) alarms.
• U – Suppresses the Over Range (OVER) alarms.
• W - Enables a warm start delay after a SCADA failover. During the warm start delay period, SAC suppresses driver alarms for the time period specified following a SCADA failover. Once the time period elapses, driver alarms are handled as usual.

You can use the W parameter to specify a delay of n seconds where n can be 1 – 300 seconds. For example, the parameter W30 causes SAC to suppress NODATA and COMM alarms for 30 seconds after a SCADA failover.

If n is outside of the acceptable range, the parameter is ignored and NODATA and COMM alarms are processed as usual after a SCADA failover.

IMPORTANT: SAC parameters do not use the slash (/) or dash (-) delimiters. Use spaces to enter optional SAC parameters. For example: S D30

 

See Also

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