Puritan PSM 156

Hello I just purchased a used Puritan PSM 156, and it's an amazing product I highly recommend! My first question for you already experienced owners,  does it normally come with a factory  manual ??? ... also the Puritan, has a special ground connection? is there some kind of extra device that attaches there? please explain if you can. and last would you plug you power amp into the Puritan?? hope someone can help me out, and thanks for your precious time  Aoltes