HP 3000 Series Installation And Service Manual page 57

Maintenance
f. Immediately discard the removed RAM chip, or mark it as
scrap, to avoid the possibility of its being inadvertently
reinstalled as a new replacement part.
NOTE
Bending the pins of the defective RAM
chip immediately upon removal is an
effective way of marking it as scrap.
g. Press a new RAM chip into the socket.
h. Reinstall the
MPU
PCA board in the computer card cage, using
the procedure described under "Installation of the INP PCAs"
in Section II, Installation.
i. Verify that the INP is now working properly
under "Installation Verification" in Section
lat ion.
as des er ibed
II,
Instal-
5-18. Replacement of the PCA Boards
When the troubleshooting procedures outlined in paragraph 5-14
indicate the need for replacement of the INP PCA boards, proceed
as follows:
a. Ensure that the system operator has backed up the system
files before beginning this procedure.
b. Turn off the power.
On the
HP
3000 Series II and the Model 32421A of the Series
III, set the SYSTEM DC POWER switch and both MEMORY DC
POWER switches to the STANDBY position. (These three
switches are located inside of the main cabinet front door,
behind the register displays, as shown in figure 2-2.)
On the HP 30 00 Series I I I, Model 324 35A, set both DC POWER
switches (the LOGIC switch and the MEMORY switch) to the
DISABLE position. (These switches are located inside of
the main cabinet front door, as shown in figure 2-3.)
CAUTION
All power must be off when in-
serting or removing any device
or card in the system.
c. Disconnect the cable hood connector and the ribbon cable con-
nectors from the edges of the INP PCA boards.
5-14