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DDY file error reading

asked 2015-09-13 22:01:23 -0500

lutinfr's avatar

updated 2020-01-20 13:40:39 -0500

I'm using Openstudio 1.8.5, when choosing ddy file that has been generated by internal E+ tool (installed with OS 1.8.5) from folder: C:\Program Files\OpenStudio 1.8.5\share\openstudio\EnergyPlusV8-3-0/preprocess/weatherconverter/weather.exe

Openstudio show error below (image), epw souce file was generated by meteonorm.

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This error does not occurs when using downloaded ddy file from

lutinfr's avatar lutinfr  ( 2015-09-13 22:03:30 -0500 )edit

Have you opened the ddy file to check if you do have design days (SizingPeriod:DesignDay) in there? can you upload or do a pastebin with the content of the ddy file?

Julien Marrec's avatar Julien Marrec  ( 2015-09-14 00:47:20 -0500 )edit
lutinfr's avatar lutinfr  ( 2015-09-15 02:44:43 -0500 )edit

1 Answer

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answered 2015-09-15 03:19:28 -0500

updated 2015-09-15 03:29:18 -0500

Your problem here is that your design day file (.ddy) has no design days. Open it up, you'll see:

  ! No Design Conditions found for this Location

You should have SizingPeriod:DesignDay objects in there: at least one, but reasonably at least 2, one for winter and one for summer, and likely more than that to cover the range of possible situations.

The underlying problem is that you're using meteonorm, and likely for a non-standard location. How to create a .ddy file has been covered on this question with a very similar problem than yours: How to generate a ddy file for E+.

Shortly: the weather converter executable from E+ installation creates the .ddy file based on ASHRAE Handbook of Fundamentals*. You don't have data. You can use the STAT file to create your design days manually or use a ddy file for a location that's close by.

(*It seems that in E v8.3.0 it's using ASHRAE HoF 2013)

Note that a SizingPeriod:DesignDay looks as follows:

  NANTES Ann Htg 99.6% Condns DB,     !- Name
          1,      !- Month
         21,      !- Day of Month
  WinterDesignDay,!- Day Type
       -4.1,      !- Maximum Dry-Bulb Temperature {C}
        0.0,      !- Daily Dry-Bulb Temperature Range {C}
 DefaultMultipliers, !- Dry-Bulb Temperature Range Modifier Type
           ,      !- Dry-Bulb Temperature Range Modifier Schedule Name
    Wetbulb,      !- Humidity Condition Type
       -4.1,      !- Wetbulb at Maximum Dry-Bulb {C}
           ,      !- Humidity Indicating Day Schedule Name
           ,      !- Humidity Ratio at Maximum Dry-Bulb {kgWater/kgDryAir}
           ,      !- Enthalpy at Maximum Dry-Bulb {J/kg}
           ,      !- Daily Wet-Bulb Temperature Range {deltaC}
    101001.,      !- Barometric Pressure {Pa}
          3,      !- Wind Speed {m/s} design conditions vs. traditional 6.71 m/s (15 mph)
         60,      !- Wind Direction {Degrees; N=0, S=180}
         No,      !- Rain {Yes/No}
         No,      !- Snow on ground {Yes/No}
         No,      !- Daylight Savings Time Indicator
  ASHRAEClearSky, !- Solar Model Indicator
           ,      !- Beam Solar Day Schedule Name
           ,      !- Diffuse Solar Day Schedule Name
           ,      !- ASHRAE Clear Sky Optical Depth for Beam Irradiance (taub)
           ,      !- ASHRAE Clear Sky Optical Depth for Diffuse Irradiance (taud)
       0.00;      !- Clearness {0.0 to 1.1}
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Asked: 2015-09-13 22:01:23 -0500

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Last updated: Sep 15 '15