Power supply for Lionel AMC/ARC Log Loader

Just hook it up to accessories.  I’m not sure that polarity matters I believe it comes with an on off switch. I hook my accessories up to small transformers so I can slow them down or easily shut them down.  I also only have cw-80’s so I don’t have a lot of power.  

Power supply means a transformer. No one sells accessories with the power supplies included.

You can use a small transformer, like a CW80, or use the accessory terminals in a larger transformer that you use to run trains.

Thanks for the responses.  Since it was talking about special A and U terminals, I had wondered if polarity mattered.  I'll just use one of the transformers I have.