IBM Power System 9009-41A Manual page 22

Figure 6. Unlocking the front door
b) Ensure that you have the electrostatic discharge (ESD) wrist strap on and that the ESD clip is
plugged into a ground jack or connected to an unpainted metal surface. If not, do so now.
c) Twist the cover latch to the left (counterclockwise) to unlock the cover as shown in Figure 7 on
page 9.
Vertical is locked; horizontal is unlocked.
8 Power Systems: Power Systems: Control panel