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A detailed description of all PI formats can be found at http://public.deltares.nl/display/FEWSDOC/The+Delft-Fews+Published+interface+%28PI%29. The latest versions of the schema files are always available at the Deltares website at: http://fews.wldelft.nl/schemas/version1.0/pi-schemas/pi_timeseries.xsd
When the time zone is not present in the PI file the default timezone configured in the general adapter or import module is used. The time zone is always written to the pi time series file when exported from FEWS.
The file format
Please consult the full documentation (http://public.deltares.nl/display/FEWSDOC/The+Delft-Fews+Published+interface+%28PI%29) and the xsd schema fro more details.
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