Add a Conduit Standard

Click Manage tabSettings panelMEP Settings drop-down Electrical Settings.
In the left pane of the Electrical Settings dialog, expand Conduit Settings, and click Size.
In the right pane, click Add Standard.
In the New Standard dialog, enter a name for the conduit standard, select an existing conduit standard to base the new standard on, and click OK.
Using the procedure above, modify the conduit sizes for the conduit standard as needed.