Digital Equipment EK-SFXXS-SG-003, Service Manual

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5–22 SF3x Storage Enclosure FRU Replacement
5.4 Replacing the Fan Assembly
Use the following steps to remove and replace the fan assembly (PN
70–24440–01):
1. At the system console, dismount
all the ISEs on that bus.
2. Take the disk ISEs in the storage enclosure off-line:
a. Press and release all Ready buttons on the OCP. Wait for the
Ready LEDs to go out.
b. Set the drive dc power switches to off . The switch element LEDs
should go out to indicate that power has been removed from the
disk ISE. If any LED does not go out, suspect a faulty switch.
CAUTION
Wear an ESD grounding strap at all times while handling the
storage enclosure or any of its FRUs.
3. Remove the OCP—grasp it firmly and pull it straight out. Do not pry;
the panel comes free with a straight pull.
4. At the rear of the enclosure, ensure that the DSSI interconnect cables
can be extended up to 3 feet.
WARNING
Take care when accessing the internal components of the
inner assembly. A stop mechanism in the chassis locks
the inner assembly at a point that allows access to the fan
assembly. This stop mechanism locks the chassis so that the
inner assembly is over three-quarters of the way out of the
chassis. If you release this stop, nothing prevents the inner
assembly from being pulled completely free of the extrusion
tube.
5. Remove the four screws in each corner of the storage enclosure.
6. From the rear, push the inner assembly out of the extrusion tube until
it latches at a position just past the top of the fan assembly.
7. Disconnect fan connector J5 from the transition module (Figure 5–6).
The fan cable is captive to the fan.
8. Loosen the four captive captive screws in each corner of the fan
assembly (Figure 5–5).