Set the Units

The exported data units are set from the working units in the seed file in use. The standard seed file supplied with Export-DGN has mm as the working units but metres, feet and inches can also be recognized if a different seed file is used.

In a DGN file the working units are described in terms of:

1. Master units, these can be named

2. Sub-units, these can be named

3. Resolution units (these are not named)

4. Number of sub-units per master unit

5. Number of resolution units per sub-unit

Firstly, AVEVA ExPLANT-I checks the master units name for millimetres (MM or mm), metres (M or m), feet (FT, ft or ‘) or inches (IN, in or ") for a positive match and if it finds one, sets the scaling accordingly.

If there is no positive match, it then checks the sub-unit name against the same unit names and if it finds a match sets the scaling from the sub-unit and the number of sub-units per master unit.

Note:
If the units in the seed file are not recognized, the default is to assume MM.