555 virtual
Virtual components are only used for simulation. These components have a symbol and a model， but no footprint； therefore they can'；t be exported to Ultiboard for PCB layout.
虚拟组件仅用于仿真。这些组件有一个标志和一个模型，但没有足迹；因此他们不能被出口到Ultiboard PCB布局。
555 timer rated
Rated components are virtual components that can be rated to blow is a pre-set tolerance is exceeded. Place one of these components and open its Properties， in the Value tab you can adjust the component’s tolerance
额定组件是虚拟的组件，这些组件可以被评为打击是预设的宽容是超过了。这些组件的地方之一，打开它的属性，在价值选项卡，你可以调节组件的宽容。
