O gauge transformer power

[bobrad20]

As a newbie to O gauge (for my grandson) but familiar with N gauge, I know squat about AC transformers and the power required for a layout. My question: what size transformer would one need for 20 feet of O gauge track? Is there a certain wattage per foot of track? If I doubled the length of track, should I also double the wattage of the transformer? Any help is appreciated.

[dmaynard]

bobrad20, You ask a very interesting question. The amount of power needed is determined by the needs of the train, not so much by the length of track. Longer track would benefit from having power feed wires attached to it at more then one place, but getting a larger power supply usually isn't necessary just because you have long track. Getting a larger power supply will supply more current, but if the track is long enough to have a voltage drop then being able to supply more current wont overcome the track losses. The way to overcome track losses is to make sure all track joints are clean and tight and to feed power into the track at multiple locations. So the short answer is no you shouldn't have to buy a larger supply for a longer piece of track. However, buying a larger supply is usually a good idea so that when you buy that extra large locomotive with the string of lighted passenger cars you will actually be able to run it.

[bobrad20]

dmaynard
Thanks for your prompt reply. You answered my question well.

[craftsmaster]

Experienced post! Thanks for the info dmaynard. I have nothing to add...thinking deeply??? Oh you can incorporate a 3 percent grade (three inches per eight-foot section) with minimal problems, but going any steeper than that inhibits the hauling power of your locomotive.