WIN-911 interfaces with OPCDA and DDE servers. These connections only transfer raw data values, rather the alarm events. As a result, WIN-911 manages all alarm conditions and alarm acknowledgments. There is no dedicated location or standardized means of communicating to the HMI that an alarm has been acknowledged in WIN-911 or vice-versa. In an effort to facilitate just that sort of interaction, WIN-911 has implemented a Group Poke feature. Combined with a bit of server side scripting, alarm states can be synchronized between WIN-911 and your server.
WIN-911 organizes alarms by Group. Each alarm must belong to one and only one Group. As the name implies, the Group Poke occurs on a Group level. The basic idea behind the Group Poke is that when an alarm in a particular Group is acknowledged, a string is written to the HMI server indicating that one of the alarms in that Group has been acknowledged. If you wish to use that information to acknowledge alarms in your HMI, you will need to write a script that listens for that text and acknowledges each alarm that belongs to that group. The text “GROUP ACKED” is used by default. As mentioned previously, the Group Poke is also capable of acknowledging alarms in WIN-911. When the text “Ack” is written to the Group Poke field, WIN-911 will acknowledge all alarms in the group. If you wish to synchronize alarm acknowledgments between your HMI and WIN-911, you will need to write scripts that acknowledge your HMI alarms when the text “GROUP ACKED” is written to your server and write the text “Ack” when an alarm is acknowledged in your server. It is recommended that the text “Ack” is written when an acknowledge button is pushed in your server, rather than when an alarm is acknowledged, otherwise it is likely that your server and WIN-911 will continuously write “Ack” and “GROUP ACKED” to the same field while repeatedly acknowledging the same set of alarms.
WIN-911 will also use the Group Poke feature to indicate when it detects an alarm by writing the name of the alarm, as well as some other information, to the Group Poke field. The format used is defined on the Format tab of Data Poke definition dialog.
The Group Poke requires you to create a writable string tag on your OPC or DDE server for each alarm group that requires Group Poke functionality. The tag must be configured within WIN-911 as well. Specify the OPC item name or DDE tag in the Group dialog on the Group Poke tab.