Is it through the rails? if so, then how? or is it by another method?
Hot rails running along side the beams Hot shoes on the crane make contact with the hot rails and slide along the hot rails. Hot rails mounted to the beams by insulating bells. The hot rails can be anywhere in size from trolley wires to rails the size of railroad track rails. AC cranes are usually 3 phase so they will have 3 hot rails. DC cranes will usually have just 2 hot rails. Main disconnect/lock out feeds hot rails. It is usually fused but can also be just a disconnect switch. The same arrangement also is used on the crane's trolley. But in the case of the trolley one set of hot rails feeds the trolley motor. One set of hot rails feeds the main hook {big hook} motor: One set of hot rails feeds the auxiliary hook motor {little hook} motor. If the crane is also used as a Mag crane {Electro magnetic can be used} it will also have a set of hot rails going to the trolley for the magnetic
