Problem

When I save my DGN to DWG I am seeing duplicated levels, where one is displaying (Construction) after the Layer name. Why and how can this be removed? 

Solution

In MicroStation you have the ability to place both Primary and Construction Class elements on the same Level and the Construction Class elements display can be toggled on and off using View Attributes.

When saving the file to DWG two Layers of the same name are created to separate these elements with one having (Construction) after its Layer name. Elements placed with Construction Element Class will be placed onto the Layer name (Construction) thus providing the ability to turn these on / off.

When saving the DGN to DWG there is an option to control the behaviour how the elements with Element Classes are handled, the switch can be found in the DWG Save Options Dialog under the Classes section.

• Save — Saves Construction elements to DWG in the same manner as Primary class elements.
• Omit — Does not save Construction elements to DWG.
• Save As Invisible — Saves Construction elements to DWG as invisible entities.
• Save To "Construction" Layer — Saves Construction elements to layers with the original layer name followed by “(Construction).” This is the default.
• Save to "Defpoints" Layer — Saves the geometry to the Defpoints layer. AutoCAD typically uses this layer for dimension definition points and other construction geometry.