IBM 7133 Series, Service Manual

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Back Backplane Assembly
| Note for Models 010 and 500: The back backplane assembly can be removed while
the disk drive modules at the front of the 7133 remain operational. Unless you have a
particular reason to do so, do not turn off the using system or the 7133 when removing or
installing the back backplane assembly.
|
1
Use the Link Verification service aid (see the chapter about SSA service aids in the
| SSA Adapters: User’s Guide and Maintenance Information manual) to ensure that all
SSA loops that pass through the front backplane assembly are not broken. (For
example, all external SSA cables are connected correctly; all disk drive modules
and, if required, dummy disk drive modules are installed correctly.)
If a loop is broken, repair it, then check whether you have solved the original
problem. If the problem remains, go to step 2.
|
2
If not already done, remove (Models 010 and 020) or open (Models 500 and 600)
| the front cover (see “Covers” on page 3-2).
|
3
On Models 010 and 500, ensure that the disk drive modules in the back of the 7133
| are no longer available to the using system.
| On Models 020 and 600, stop all operations on the 7133, then remove all power
| from the 7133 (see “All Power” on page 3-7).
4
Remove the two back-power cards from the front of the 7133 (see “Back-Power
Cards” on page 3-41).
|
5
On Models 500 and 600, open the back cover (see “Back Cover (Models 500 and
| 600 Only)” on page 3-6).
|
6
Carefully make a note of the locations of the disk drive modules and (if present)
| dummy disk drive modules that are at the back of the 7133. This action ensures
| that you reinstall the modules into their original slots. (They might not all be
| connected to the same SSA loop.) Attach identifying labels to the modules if you
| want to.
7
Remove all the disk drive modules and dummy disk drive modules from the back of
the 7133 (see “Removing a Module” on page 3-17).
|
8
At the back of the 7133, do the following actions:
| For Models 010 and 500:
| a. Disconnect the external SSA cables (if present) from the two back-signal
| cards. To prevent damage to the SSA connector screws, ensure that you
| use the special screwdriver (SSA tool, part 32H7059) to unscrew them. The
| screwdriver is supplied with the 7133.
| b. Remove the two back-signal cards (see “Signal Cards and Bypass Cards”
| on page 3-43).
| For Models 020 and 600:
| a. Disconnect the external SSA cables (if present) from all four bypass cards.
| To prevent damage to the SSA connector screws, ensure that you use the
| special screwdriver (SSA tool, part 32H7059) to unscrew them. The
| screwdriver is supplied with the 7133.
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7133 Service Guide