Guidelines for Specifying Units
Before you specify a system of units for your model, read these guidelines:
• Default System of Units—If you do not specify a system of units, Creo Parametric uses inch pound-mass second (inch lbm second) as the default system of units. You can change the default principal system of units using the PRO_UNIT_SYS configuration option.
You can also set a principal system of units in Creo Parametric when you click > > 
Model Properties to open the Model Properties dialog box.
Model Properties to open the Model Properties dialog box.• Units for Parts and Assembly—You can specify units in part or assembly mode. You can open an assembly model in Creo Simulate even if the individual component parts have different systems of units, provided the units of length are the same for the assembly and the individual components.
• Density—Creo Parametric displays density as mass per unit volume, not weight per unit volume.
• Simulation Entities—Creo Simulate allows you to select units for many different simulation entities in your model such as loads, constraints, materials, idealizations, properties etc.
• Using Parameters with Units—In Creo Simulate, for all simulation entities for which you can select units, you can also use parameters with units or expressions of parameters that evaluate to units of the same dimension as the simulation entity.
• Units in Result Windows—Creo Simulate allows you to select units for result quantities.
• Material Library—Creo Parametric displays only materials with units in the material library.
Return to About Units.