IBM 7015-R30, Installation And Service Manual

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4-6
Service Guide
Note: For a translation of this notice, see the System Unit Safety Information manual.
DANGER
An electrical outlet that is not correctly wired could place hazardous voltage
on metal parts of the system or the devices that attach to the system. It is the
responsibility of the customer to ensure that the outlet is correctly wired and
grounded to prevent an electrical shock.
Before installing or removing any additional devices to or from the system,
ensure that the power cables for those devices are unplugged before the signal
cables are connected. If possible, disconnect all power cables from the existing
system before you add a device.
Use one hand, when possible, to connect or disconnect signal cables to prevent a
possible shock from touching two surfaces with different electrical potentials.
During an electrical storm, do not connect cables for display stations, printers,
telephones, or station protectors for communications lines.
Attention: This unit may have more than one power supply cord. To completely remove
power, you must disconnect all power supply cords.
3. Switch off power to all external devices attached to the system unit, and then unplug the
device power cords from the electrical outlets.
Note: Because many external devices can be connected to the system unit, it may be
impractical for you to switch off power to all the devices and unplug their power
cords.
4. Open the back door of the rack.
5. Set the Master CB1 circuit breaker to Off.
6. If the battery backup unit is installed, set the Master CB2 circuit breaker to Off.
7. Unless you are servicing the system while signal cables or power cords are connected to
external devices, unplug the system unit power cord from the electrical outlet.
Battery
Backup
Unit
Power
Distribution
Unit
Master
CB2
Master
CB1
Power
Distribution
Unit
Rear View
of Rack