HP Surestore Tape Library Model 20/700 Installation Instructions Manual page 3

WARNING:
THE CURRENT GRATING UNDER THE ELECTRONICS MODULE
ALLOWS SMALL ITEMS (NUMBER 4 SCREWS) TO FALL THROUGH
THE FAN ASSEMBLIES. LIKEWISE, THE GRATING ON TOP OF THE
POWER SUPPLIES (IDENTICAL) WOULD ALLOW SMALL ITEMS
DROPPED FROM ABOVE TO FALL THROUGH AND INTO THE DC
POWER SYSTEM. AT THIS TIME WE ADVISE PLACING A PIECE OF A
CARDBOARD OR AN ESD BAG UNDER THE MPC CONTROLLER
(BOTTOM OF THE ELECTRONICS MODULE) WHILE REMOVING THE
MPM AND WHILE ATTACHING THE CPCI CARD CAGE. BE SURE TO
REMOVE AFTER INSTALLATIONS ARE COMPLETE (SEE FIGURE 3).
Figure 3. Grating under Electronic Module
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