HP 3000 Series Installation And Service Manual page 56

Maintenance
5-16. FIELD REPAIR
Field repair of the !NP is limited to the following procedures
and is to be accomplished only by Hewlett-Packard support per-
sonnel.
5-17. Field Replacement of a RAM Chip
The Randan Access Memory (RAM} chips are the only components on
either of the !NP PCA boards that are field replaceable. (See
figure 5-1 for their 1 oca ti on on the board.) If troubles hooting
procedures (such as use of the self test) indicate that a RAM is
faulty, replace it 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 posit ion. (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 3000 Series III, Model 32435A, 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 pc:Mer must be off when in-
serting or removing any device
or card in the sys tern.
c. Disconnect the ribbon cable from the !NP PCA boards.
d. Remove the INP-MPU PCA board (part no. 30010-60001) fran the
card cage.
e. With the INP-MPU board lying on a smooth, firm surface, with-
draw the defective RAM chip out of its socket with a chip
ex tr actor tool.
5-13