Most DCC command stations will automatically shut down if the current load exceeds a limit. If you short the rails on your Power Cab, it will automatically reset. So if your Power Cab is not reseting, the current load isn't too much. See Mark Gurries webpage for more info.
On the other hand, you didn't mention what decoder is in your locomotive. One you find out, google it to find its current rating.
greg - Philadelphia & Reading / Reading
Yes to your first question and no to your second. As you put more trailing resistance on the locomotive by adding cars, its amperage draw will go up. The NCE system you describe must have at least two (2) amps of capacity throughput, but I confess I know nothing about that particular system. The only system I know of that does/did have one amp of capacity was the Bachmann EZ-Command launched about eleven years ago.
My HO MTH Yellowstone is operated with a NCE Power Cab DCC system. The engine is pulling 42 cars on my layout with 34" minimum radius. When operating it draws as much as .90 amps. Is that normal? Is it too much for the decoder or my NCE system? Thanks.