MicroStation
MicroStation Training
MicroStation
MicroStation Training

How to define the work units used in MicroStation

Preamble

MicroStation and all applications based on the same platform (OpenBuildings, OpenRoads, iTwin Capture Modeler,...) allow to use and modify the unit system at any time.

In short, we can say that MicroStation retains the size of the elements: the unit is there only to establish the measurement.

Prenons l’exemple d’un élément ayant une dimension de 2.54m. Si on change l’unité de travail en pouce par exemple, sa dimension sera alors de 100″. La grandeur Physical the element remains unchanged.

This concept is obviously very practical when working with different techniques and the notion of a reference file or cell is widely used: topographers, road projectors tend to work in "meters", architects in "centimeters" and mechanics in "millimeters".

By default MicroStation offers a set of units of measurement. Some of them are useless for your particular use: rare are those in continental Europe who work in imperial units. So we can remove them from the list without any worries.

How?

This can be controlled using a combination of the variable MS_CUSTOMUNITDEF and the unit definition file, units.def. 
File units.def is a default ASCII text file in the folder ... / Workspace / System / Data  . 
Variable MS_CUSTOMUNITDEF Point to this file.

  • Work units available in a file can be found in Specification > Drawing file under category Work units. If you are in CONNECT Edition, you will need to click on the menu File > Specifications > File > Specifications drawing file to access the screen in which you will find the category Work units.
  • By default, the available work units are visible in the image below:

  • To change the list of available units, access the file units.def (location designated by MS_CUSTOMUNITDEF).
  • Copy the file units.def (e.g.: my_units.def)
  • Open copied file my_units.def with a text editor such as the Notepad Windows (Notepad)
  • Add the sharp symbol (#) in front of all units that no longer need to be displayed, this will result in deactivated units without removing them
  • Save file
  • Edit variable MS_CUSTOMUNITDEF and modify its content to designate the newly created file (my_units.def).
  • Restart MicroStation and check that only the desired work units are displayed: