Lever is obtained as which is the mechanical advantage of the lever. This equation shows that if the distance "a" from the fulcrum to the point "A" where the input force is applied is greater than the distance "b" from fulcrum to the point "B" where the output force is applied, then the lever amplifies the input force. If the opposite is true that the distance from the fulcrum to the input point "A" is less than from the fulcrum to the output point "B", then the lever reduces the magnitude of the input force. Lever A lever ( or )
Lever frame required to move them. Mechanical lever frames and interlocking have now largely been replaced by modern, much larger electrical or electronic route interlockings located in Power Signal Boxes and more recently Integrated Electronic Control Centres which are able to control much larger areas of the rail network. A mechanical lever frame is designed to harness mechanical advantage to operate switch points, signals or both under the protection of the interlocking logic. The levers are connected to field appliances via solid pipes or taut wires such that the full travel of the lever will reliably cause full travel in the appliance.