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.
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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