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02/12/2016
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Hello ,
With reference to Part 13-OPC UA Specification, I have the following clarification
The TimeAverage aggregate results described for Historian2 in section A.4.2 has the following result for one of the intervals
I suspect the computed result is incorrect or I have no clue how the following interval is computed.
The relevant input samples for this interval are
12:00:45.000 –>value= 36.667 (uncertain,Interpolated)
12:00:48.000–> value=40 (Good,Raw data sample)
12:00:50.000–>value=50(Good, Interpolated)
As per my understanding ,the area under this interval comes as 210 and the Time average =Area/interval=>210/5=42
Please correct me if there is any mistake in my calculations
or
Justify the output described in the document for this interval
12:00:45.000 | 40 | UncertainDataSubNormal, Calculated |
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02/24/2014
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Hello,
Here is your mistake:
12:00:50.000–>value=45(Good, Interpolated) not 50 as you listed – the table lists the time stamp for the value of 50 as 12:00:52.000, which interpolates to 45 as the ending value. The area under the curve is 200 -> 200/5 = 40 So the computed average is correct.
Paul Hunkar - DSInteroperability
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