Chapter 2. Maintenance Analysis Procedures (Maps); Map 1520: Dc Power Distribution Panel - Power Map; Purpose Of This Map; Safety Notices - IBM T00 Service Manual

Chapter 2. Maintenance Analysis Procedures (MAPs)

This chapter provides diagnostic steps for detecting power problems in the rack. Use these power MAPs
only if you are directed here from a MAP step in the Diagnostic Information for Multiple Bus Systems.
If your rack has a power distribution panel, follow the instructions for "MAP 1520: DC Power Distribution
Panel - Power MAP."
If your rack has a power distribution bus, follow the instructions for "MAP 1522: AC Power Distribution Bus
- Power MAP" on page 21.

MAP 1520: DC Power Distribution Panel - Power MAP

Purpose of This MAP

This procedure is used to locate power problems in the dc power distribution panel. If a problem is
detected, this procedure helps you isolate the failing field replaceable unit (FRU).

Safety Notices

Observe the following safety notices during service procedures.
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 signal cables, ensure that the power cables for the system unit
and all attached devices are unplugged.
When adding 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.
D05
CAUTION:
Energy hazard, remove power before servicing. Disconnect two power supply cords.
C23
Step 1520-1
Do any of the devices in the rack have their power indicator(s) lit? (front operator panel or power
supply LED).
NO Go to "Step 1520-10" on page 19.
YES Go to "Step 1520-2" on page 18.
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