On Nov 7, 13:43, John Willis wrote: The Field Maintenance print sets for the PSUs and the power controller are available at http://208.190.133.201/decimages/moremanuals.htm (part of the DFWCUG Historical CPU Preservation Society). They are BIG files. If an 875 power controller is like an 876, then if the lights don't come on, reset your breaker :-) I don't know about the H7104's (I've never seen one up close). I assume there is something plugged into the 3-pin Power Bus connector, or you have the three-way switch in the "local" position, otherwise it won't turn on. -- Pete Peter Turnbull Network Manager University of York