From the Toolbar: Find the Translate UCS Origin Along Z-Axis Tool icon on the UCS Draw Plane Toolbar (color coded purple) and Click on the tool. The tool is now active and ready for use.

 
From the Shortcut Key: This tool does not have a default shortcut key.

 
From the Command Line: Type "translate_ucs_on_z_axis" into the Command Line, at the top of the notification window, and press the Enter/Return key.

1.        Click anywhere on screen when desired distance is achieved for translation.

Reset:

After translating the UCS the tool will automatically reset. You can choose a different tool or translate UCS along z-axis again.

1.        Type the distance data into the "Distance" Scientific Data Field found on the Tool Property Tree and press Enter to accept.

Reset:

After translating the UCS the tool will automatically reset. You can choose a different tool or translate UCS along z-axis again.

Escape (Esc): Cancels current tool and activates the default tool (Selection Tool).

Space: Resets this tool.