To Create a Custom Units System
1. Click File > Prepare > Model Properties. The Model Properties dialog box opens.
2. Click change in the Units line. The Units Manager dialog box opens to the Systems of Units tab , which lists all available custom and system-defined units systems. A description of the selected units system appears under Description.
3. Click the New button. The System of Units Definition dialog box opens, showing the units for the predefined system.
4. Under Name, type a name for the new unit.
5. Under Units, select the desired types of units in the appropriate drop-down lists. You can select either Mass or Force units by clicking the Mass or Force button.
6. Click OK to return to the Units Manager dialog box. The new system appears in the list.
7. Select the new units system and click Set to assign your custom system of units to your model.
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Use the Copy button to create a copy of the selected units system with a different name.
You cannot edit or delete the systems of units provided by the system. System-provided units systems are indicated by the PTC icon under Description.