IBM EXN1000, Hardware And Service Manual, Page: 64 / 94

Rules for replacing power supplies
When replacing a power supply on your EXN1000 expansion unit, observe the
following rules:
v You do not need to turn off the power to the expansion unit when you
replace one power supply, only the power supply that is being replaced.
v
If you are replacing both power supplies in the same EXN1000 expansion
unit, replace them one at a time to avoid powering down the EXN1000
expansion unit.
v Although a single fan failure in one of the power supplies is not a critical
event, it is recommended that you install a new power supply when one of
the two fans in either power supply stops working.
v
When hot-swapping power supplies, remove and install the power supplies
within two minutes.
Attention: Your EXN1000 can run with one power supply removed for a
maximum of two minutes. The airflow through your EXN1000 is degraded
when only one power supply is present and operating. Therefore, if the power
supplies are not replaced within two minutes, the system halts and no data is
accessible.
v
Have the replacement power supply close by and ready to install before
removing the old one.
CAUTION:
Never remove the cover on a power supply fan unit. There are no
serviceable parts inside these components. If you suspect a problem with
one of these parts, contact a service technician.
Removing a power supply
To remove a power supply, complete the following steps:
1. Put on the antistatic ESD strap and grounding leash.
2.
Turn off the switch on the power supply that you are replacing.
3. Lift up the clip lock and unplug the power cord from the N series storage
system power supply.
4. Using your thumb and index finger, press the cam mechanism levers
toward each other to release the power supply handle. The following
figure shows how to press the levers on the cam mechanism and release
the power supply handle.
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