IBM THINKPAD T42 -, Service Manual

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AC Power Distribution Bus Illustration
When the drawer power cords are plugged into the outlets, there should be less than 1 ohm resistance
between the drawer frames or the rack frame.
Power
Distribution
Bus
Outlets for
Peripherals
(Two Facing
Front of Rack)
Optional Drawer
Optional Drawer
Optional Drawer
Disk Drive
Drawer
Disk Drive
Drawer
Main
Main
Main
Drawer
Power
Cords
CPU
External AC Power Cables
To avoid electrical shock, the manufacturer provides a power cable with a grounded attachment plug. Use
only properly grounded outlets.
Power cables used in the United States and Canada are listed by Underwriter’s Laboratories (UL) and
certified by the Canadian Standards Association (CSA). These power cords consist of the following:
v Electrical cables, type ST
v Attachment plugs complying with National Electrical Manufacturers Association (NEMA) as well as other
UL recognized or UL-listed electrical suppliers.
v
Appliance couplers complying with IEC Standard 320, Sheets C13, C14 and IEC Standard 309.
To find the power cables that are available for the ac rack, refer to “Power Cords” on page 55.
Uninterruptible Power Source
An uninterruptible power source (UPS) can be installed in the rack that contains an ac power distribution
bus. The uninterruptible power source powers one drawer or device. The uninterruptible power source
contains a power plug (input) and one power outlet (output). IBM offers several UPSs as type 9910 in the
pSeries configurator.
Chapter 1. Reference Information
9