CCM-Editor FAQ & Help

A climate contains meteorological data sets. These can be generated from measurements and/or algorithms. For most simulation programs, climate data such as outside air temperature and humidity and radiation intensities are important and are used as input parameters for calculations. This can then be used to carry out simulation-based analyses, e.g. of a building model or construction details.

The physical sizes can be stored in various file formats, both in ASCII files and in binary format. The 3 most important formats that can be read directly by the CCM Editor are briefly described below.

C6B

The C6B climate data format was developed at the Institute of Building Climatology at TU Dresden and represents annual data sets and continuous climate data sets. The format contains the following data:

• Air temperature in [C]
• Relative humidity in [%]
• Direct normal radiation in [W/m2]
• Diffuse horizontal radiation in [W/m2]
• Wind direction in [°]
• Wind speed in [m/s]
• Long-wave sky counterradiation in [W/m2]
• Air pressure in [Pa]
• Precipitation on a horizontal surface [l/m2h]

The data is stored in a binary format (primarily for legal licensing reasons). For larger (multi-year) climate data, reading the file is faster, and there is no need to check valid number formats when reading in the data. In variation studies (Monte Carlo analyses, sensitivity studies, etc.), in which many fast DELPHIN simulations are started, reading and processing the climate data sometimes takes a lot of time.

EPW

The EPW format is a simple ASCII text format. It is supported internationally by many simulation programs. There is also a Weather Data database on the EnergyPlus website. It offers a wide range of climate data from various locations around the world. The format supports the following data:

• Air temperature (dry and dew point)
• Relative humidity
• Sky counterradiation
• Solar radiation (global, direct, diffuse)
• Light data (illuminance global, direct, diffuse)
• Wind data (speed, direction)
• Sky coverage
• …​

The EPW format defines one or more start and end times (1.1. – 31.12.). The intervals are also defined (e.g. hourly data or quarter-hourly data).

WAC

The WAC format was introduced by the Fraunhofer Institute for Building Physics in Holzkirchen primarily for hygrothermal simulations. It can be processed natively by DELPHIN and is suitable as an ASCII format for simple editing in the text editor. In principle, WAC files contain the same climate data as c6bfiles. Solar radiation is specified either as direct horizontal radiation or global radiation on a horizontal surface. Compared to EPW, the format is somewhat easier to generate from spreadsheet programs (Excel, LibreOffice/Calc, etc.), but is otherwise equivalent.

Climate data sets can be annual data in hourly grids (common for annual or multi-year cyclical data). If you want to create climate data sets from measurement series, you may need different time grids or flexible time steps. Measurement series also often begin in the middle of the year.

The CCM Editor distinguishes between the two time series variants when entering data. Therefore, when creating a new climate dataset, the setting must be made as to whether it is an annual dataset or a flexible time grid.

The choice between hourly annual data and flexible times can only be selected when creating a new climate data set. Subsequent conversion is not possible.

However, it is quite easy to transfer the data from an hourly annual data set to a flexible time grid by copying the data series into a spreadsheet, creating a new climate data set and copying the data back again

When selecting annual data records with hourly data, the table has exactly 8760 rows and the times are defined for each row. When using flexible points in time, the table initially only contains 2 rows. Additional lines can be added with or removed with .

The table shows the climate data in tabular form. These can be edited by double-clicking on a cell or entering a number. Each value entered is checked for validity. Entries that are not recognized as numbers are not accepted by the editor. If a numerical value is outside the accepted value range, the value is accepted but marked as incorrect in red.

A value of ---indicates that no valid value exists in this cell. This corresponds to an incorrect value. Depending on the content of a table column, the header row is colored differently to clarify the status.

If no data is available for a climatic variable (usually precipitation or pressure), the heading of the table column is grayed out.

If all values are entered, i.e. not a single incorrect value remains in the table column, and at the same time all values are within the accepted value range, the table heading is written in normal black. As soon as at least one value is entered in a cell, the system checks whether all other values in this data series also contain values. If values are missing, the header of the column is displayed in red and the cell in which the first value is missing is noted in the tooltip (move the mouse over the column header).

If a value is entered somewhere in a table column that is outside the accepted value range, the row header is also colored red in this case. In this case, the tooltip again shows the line in which the first incorrect value is located.

CCM-Editor checks entered data for plausibility. Valid values lie within the following (in some cases quite broad) value ranges:

• Temperature [-100,+100] in C
• Relative humidity [0,100]in %
• Radiation values [0,1500]in W/m²
• Wind direction [0,360]in °
• Wind speed [0,120]in m/s
• Air pressure [0,200000]in Pa
• Rainfall [0,100]in l/m2h

Using various methods, the CCM Editor can be used much more efficiently and extensively than seems possible using the user interface alone. A compact introduction to the most important parameters of a climate data set or the advantages and disadvantages of data sets with flexible time stamps can be found in the manual. You can find further ideas for this in the tutorials and the manual or take a look at the documentation.