Condition acknowledgement alarm model

For condition-oriented alarms, an acknowledgment counts against all entries into the alarmed state up to the time of the acknowledgment.

Acknowledgment is for the instance of the alarm. An alarm instance waits for an acknowledgement when it first enters the alarmed state. If the alarm is acknowledged and subsequently transitions to a new alarmed sub-state (for example from "Hi" to HiHi"), it begins waiting for another acknowledgement. Whenever the acknowledgement is received, it is accepted and applies to all transitions of the alarm that have occurred so far.

The alarm is considered acknowledged when the most recent instance is acknowledged.