Use the plan-readability settings to make label text readable in a normal plan view.
When you select the plan-readable option, label text is rotated to a consistent readable angle.
You can specify the angle at which to start flipping labels. By default this angle is set to 110 degrees. That means that as soon as the angle of the text goes beyond 110 degrees, the label will flip 180 degrees to remain plan-readable.
The following illustration shows labels with Plan Readable set to False. Note the label at the bottom of the illustration:
The following illustration shows labels with Plan Readable set to True:
