OPC Alarms and Events
- acknowledge alarms and add comments
- request extra ‘attributes’ that a server may make available.
The connections between an OPC alarms and events client and the Gallagher server are in the form of ‘subscriptions’, where the client registers a subscription to the server. This subscription can be for all, or a filtered subset of the server alarms and events.
Third party systems such as CCTV, time and attendance, pager systems, building management systems (e.g. lighting and air conditioning systems) which have an OPC alarm and events client running can subscribe to and receive the relevant data from the Gallagher OPC server operating on the network. A CCTV system, for example, can receive specific types of messages via its OPC client. When an event occurs, the CCTV system reads the event message and initiates a sequence of actions such as starting a video recording or zooming into a specific area.
One or more OPC clients can access the data on Gallagher Command Centre and use it as required. This system is very efficient; the server will send all subscribed events and alarms to the client without being continually polled, thus reducing system load.
Alarms and events can be communicated in a variety of ways to people monitoring them, for example, via SMS, pagers, popup windows, email and webpages.