Author: http://www.munckcranes.com/ Capacity –The maximum weight the crane will be required to lift. Span –The horizontal distance between the rails of the runway on which the crane is to travel. Lift or Hook Height –The required distance from the floor to the crane hook. This dimension is critical in most applications as it determines the height of the runway from the floor and is dependent on the clear inside height of the building. Bridge, Trolley and Lift Speeds –The rate at which the bridge or trolley travels, or at which the hoist lifts, usually in feet per minute or FPM. You may specify either Single Speed or Two Speed travel/lift or a specific rate of speed, (i.e. 120 & 30 FPM bridge travel). Another option as far a motion speeds are concerned is a Variable Frequency Drive. See the Control section for more information.