I recently bought a MTH Pennsylvania 9915, I am running it on fastrack from a Lionel starter set that came with a CW40. When I use the 9915 it will only run with the engine, tender, and one car without a light. If I add a lighted caboose it will not run. I guess the 9915 is using up the 40 watts? No accessories are added to the transformer. Only one terminal track on an oval that spans my 4x8 table.
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