5.4.3.35 WorstQuality

The WorstQuality Aggregate defined in Table 83 returns the worst status of the raw values in the interval where a Bad status is worse than Uncertain, which is worse than Good. No distinction is made between the specific reasons for the status. The server shall ignore the TreatUncertainAsBad for this aggregate.

If multiple values exist with the worst quality the MultipleValues bit is set. If multiple values exist with the worst quality but different StatusCodes then the StatusCode of the first value is returned.

This Aggregate returns the worst StatusCode as the value of the Aggregate.

The timestamp is always the start of the interval. The StatusCodes are Good, Calculated.

Table 83 – WorstQuality Aggregate summary
WorstQuality Aggregate Characteristics
TypeCalculated
Data TypeStatusCode
Use BoundsNone
TimestampStartTime
StatusCode Calculations
Calculation Method

Custom

Always Good

Partial

Set Sometimes

If an interval is not a complete interval

CalculatedSet Always
InterpolatedNot Set
RawNot Set
Multi ValueUsed
StatusCode Common Special Cases
Before Start of DataBad_NoData
After End of DataBad_NoData
No Start BoundNo special handing required
No End BoundNo special handing required
Bound Bad No special handing required
Bound UncertainNo special handing required