A PPT (02+) with animated sequences demonstrating how the safety fuse requires a connection to earth in order for it melt during a fault. During animations a bar appears under the navigation buttons that wipes across until the animation has finished; it can be paused. For the buttons to work, the macro security level has to be set to medium. This is very easy and only needs to be done once; it will not compromise your computer. Select then then select. This is for ver. 2002; it might be different for later versions. COMMENTS WILL BE MUCH APPRECIATED