Specify the Alert Notification Requirements

The SCADAPack x70 tab on the Forms of SCADAPack x70 Analog Configuration items contains an Alert Notifications section. Use the section to reduce the requirement for the SCADAPack x70 device to needlessly report, and the SCADA master(s) to needlessly process, insignificant fluctuating value changes around an Alarm Limit. You do this by specifying the criteria by which the SCADAPack x70 device deems the analog to have traveled past an Alarm Limit.

To be deemed to have transgressed an Alarm Limit, the analog's value has to continuously reach or exceed that Alarm Limit for a specified time.

For the analog's value to be deemed to have returned to within a limit boundary (and so have 'cleared' an alert), that value change has to fulfill both of the following criteria:

• The analog's value has to have remained within the relevant Alarm Limit for a specified time
• The analog's value has to change beyond that Alarm Limit value by at least a specified amount.

(Either criterion might be set to 0, in which case that particular criterion will always be satisfied.)

• Alert Set Time Deadband—Use to specify the amount of time that the analog's value has to have continuously reached or exceeded an Alarm Limit, before it is considered to have transgressed that limit. If the analog's value has continued to remain at or past that limit for the duration of the deadband, the SCADAPack x70 device deems the analog to have transgressed that limit.

  The deadband's timer resets whenever the analog's value reverses its direction of travel so that it no longer exceeds that Alarm Limit.

  You can specify a value between 0 and 65535 seconds inclusive. The default is 0 (resulting in no time deadband). Enter the required interval in the OPC Time Format. You can enter the value directly in the field, or use the Interval window (accessed via the field's browse button) to specify the required value.

• Alert Clear Time Deadband—Use to specify the amount of time that the analog's value has to have returned to, and continuously remained, within an Alarm Limit, before it is considered to be back within that limit. If the analog's value has continued to remain within the limit for the duration of the deadband, the SCADAPack x70 device deems the analog to have returned to within that limit.

  The deadband's timer resets whenever the analog's value exceeds the Alarm Limit.

  You can specify a value between 0 and 65535 seconds inclusive. The default is 0 (resulting in no time deadband). Enter the required interval in the OPC Time Format. You can enter the value directly in the field, or use the Interval window (accessed via the field's browse button) to specify the required value.

• Alert Clear Value Deadband—Use to specify the amount by which the analog's value has to travel beyond an Alarm Limit, before it is considered to have traveled past that limit. Use this property to help avoid generating excessive alerts (alarms) when a value is fluctuating around an Alarm Limit.

  You can specify a value that is within the minimum and maximum Engineering range for the analog (see Specify the SCADAPack x70 Device's Point Scaling). The default is 0 (resulting in no deadband).

  If this Analog Configuration item is associated with a protocol-specific SCADAPack x70 Analog Point, that point will inherit the analog's Alert Clear Value Deadband value (see the relevant Analog Point configuration section in this guide).

• Event/Alert Inhibit Enabled—Select the check box if the SCADAPack x70 device is to generate, store and report events and alerts (alarms) for the analog whenever that analog is deemed to have traveled past an Alarm Limit. This setting only applies when using a communications protocol that supports, and is configured to enable, event generation.

  Clear the check box if the SCADAPack x70 device is not to generate, store or report events and alerts for the analog whenever that analog is deemed to have traveled past an Alarm Limit. This is the default setting. The SCADAPack x70 device will still report the analog's value changes to Geo SCADA Expert whenever a deadband expires, but as current values rather than as events or alerts.