Sequential Persistence is when the separate Persistence durations of an analog point are configured so that:
- Each High limit has a Persistence that is greater than, or equal to the Persistence of all the High limits below it.
- Each Low limit has a Persistence that is lower than, or equal to the Persistence of all of the Low limits above it.
NOTE: Sequential Persistence only applies to analog points used by Field Devices that support a separate persistence for each limit.
Example:
Low 1, Persistence: 2S
Low 2, Persistence: 4S
Low 3, Persistence: 6S
Low 4, Persistence: 8S
This means that the Persistence Durations will expire in sequence, i.e. in Alarm Limit order. For example, if a point's value crosses Low 1 and Low 2 at the same time, the Persistence Duration for Low 1 will expire before the Persistence Duration for Low 2.
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