How many wheels on a locomotive actually drive (move) a locomotive? If there are 2 or more locomotives do they trasfer all power to one locomotive or each to it’s own?
If all your locomotive drive wheels are powered than they all contribute to the tractive effort. In the case of steam engines where there will be pilot wheels and trailing trucks than just the powered drivers will deliver power to the rails. If you are running all diesels than all the drivers will contribute some power if none are dragging or slipping.
Pete
Steamers have only part of their weight on the drivers, and that is a problem with them. They can’t start the same tonnage into motion on a given length of track that a comparably weighted and powered diesel can. However, in both cases, they only drive themselves.
-Crandell
If each diesel has its own engine, then each engine supplies power to its own traction motors to make the tractive force that will move the train. However, in the case of a powered unit mated with a non-powered slug unit, then the first engine’s diesel will supply power to all the traction motors to make the tractive force that will move the train.
Oh, and another qualifier. Some diesel engines have a power truck that has an unpowered axle. In this case only the powered axles receive power from the engine, and the motor-less axle is there to distribute the weight.