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[EnergyPlus_Support] Re: Questions about converting weather files from FMT to EPW

> 
> 1. I have some differences in "header information (Typical/extreme periods & Ground temperatures)" between converted file and file from EnergyPlus website. Do the differences affect a big differences in result of simulation? If so, how can I fix it?
 
The typical and extreme periods are calculated based on the data that is in the weather file.  There is a way you can access them but whether that makes a difference in the simulation is a question.  You should compare the two "stat" files for a more overall picture of the differences between the files.  The source data is important.  Are they both typical files of a period of record?  More details can be found in the Auxiliary Programs document.

> 2. I have some difference in "Field data source and uncertainty flags" bewteen two files. Does the difference affect a big difference in result of simulation? If so, how can I fix it?

The data source and uncertainty fields are not used in the simulation. when we convert the DOE FMT file -- we have to make something up for those as there is nothing of that nature on the DOE file.
> 
> 3. According to EnergyPlus manual, there are 32 actural data in EPW files (i.e., Dry bulb temp., Dew point temp. etc). However, when I opened the EPW file which was gotten from EnergyPlus website, there were 35 actural data. Do you have any ideas what the three extra data are?

Not sure what you are referring to.  Now we do have Albedo, Liquid Precip and Liquid Precip Rate.  These are detailed in the EPW format description in the Auxiliary Programs document.  You can also view the "header records" of each data column by saving the EPW file as a "EnergyPlus CSV" file and then open it in a spreadsheet program.

> 4. As it stated in EnergyPlus manual, DOE-2 weather file has less weather data than EnergyPlus weather data. Does this affect  big differences in result of simulation? I do not need to simulate illuminance and so on.

As I remember, DOE only has two of the solar radiation components and the weather converter has to fill in the other.  One of the ones DOE has is Global Horizontal which EnergyPlus doesn't use.  To see the differences, again look at the stat file or perform the simulation though solar and other weather factors may not be the major difference between the two runs.



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