The working Length unit displays in the lower left-hand corner of the Structure view. The following figure shows the units set to inches (in).
Changing the working Length unit does not alter the actual size of the geometry, it only changes the units in which its parameters are expressed. You can change this parameter for the current model, or set it for all future models.
You should choose the predominant Length unit of your structure as your working unit. For example, if most of the features on your structure are dimensioned in meters, set your units to meters, not millimeters.
Analyst supports geometric sizes over a range of 1e-5 to 1e+4 working length units. For example, if your working cm, you should avoid geometry smaller than 1e-5 cm and larger than 1e+4 cm. Geometric entities with sizes outside of this range can cause unpredictable errors, especially on the low end. The errors may vary but the most common one is "Model dimensions are beyond the recommended range of 1e-006 to 1000 working units. Please consider changing your working unit."units are set to
To change the default length unit to inches from centimeters:
On the Home ribbon in the Settings group, click Units to display the Working Units dialog box.
To change the working units in the current model, for Length units, select in (inches).
To set the default Length parameter to inches for all future models, right-click the parameter name Length, then choose Set as Preference > User and click .