The Workgroup Server (WS) 8150 "Getting Started" manual states on page 15, "it is recommended that you lock the power switch on by turning it to the horizontal position. In the case of power failure, the server will start up automatically. ... When the power switch is locked on, you cannot turn the computer off by choosing Shut Down."
Engineering reports that the Power Macintosh 8100 and WS 8150 computers are behaving correctly. The documentation is not correct. If you choose the Shut Down command the computer will shut down, no matter if the power switch is locked on or not.