step 1 press the power switch on the ac-input power supply down to the off (o) position (see figure 4-5).
there are two on/off switches on a 4200 w ac power supply, one for each input.
step 2 loosen the side-clamp screw on the right side of the power cord plug (see figure 4-6).
step 3 disconnect the power cord from the power supply being removed.
step 4 loosen the two captive screws (see figure 4-7).
use both hands to grasp a power supply.
step 5 grasp the power supply handle with one hand. place your other hand underneath to support the bottom of the power supply, as shown in figure 4-8.
step 6 pull the power supply out of the bay and set it aside.
blank faceplates and cover panels serve three important functions: they prevent exposure to hazardous voltages and currents inside the chassis; they contain electromagnetic interference (emi) that might disrupt other equipment; and they direct the flow of cooling air through the chassis. do not operate the system unless all cards, faceplates, front covers, and rear covers are in place. statement 1029
step 7 if the power supply bay is to remain empty, install a blank power supply filler plate over the opening. secure the filler plate with the two mounting screws and tighten them with a screwdriver.