Lenovo BladeCenter HX5 1909, Problem Determination And Service Manual

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4. Remove the cover.
5. Check for any obvious non-IBM alterations. Use good judgment as to the safety of any non-IBM
alterations.
6. Check inside the system for any obvious unsafe conditions, such as metal filings, contamination, water
or other liquid, or signs of fire or smoke damage.
7. Check for worn, frayed, or pinched cables.
8. Make sure that the power-supply cover fasteners (screws or rivets) have not been removed or tampered
with.
Guidelines for servicing electrical equipment
Observe these guidelines when you service electrical equipment.
• Check the area for electrical hazards such as moist floors, nongrounded power extension cords, and
missing safety grounds.
• Use only approved tools and test equipment. Some hand tools have handles that are covered with a soft
material that does not provide insulation from live electrical current.
• Regularly inspect and maintain your electrical hand tools for safe operational condition. Do not use worn
or broken tools or testers.
• Do not touch the reflective surface of a dental mirror to a live electrical circuit. The surface is conductive
and can cause personal injury or equipment damage if it touches a live electrical circuit.
• Some rubber floor mats contain small conductive fibers to decrease electrostatic discharge. Do not use
this type of mat to protect yourself from electrical shock.
• Do not work alone under hazardous conditions or near equipment that has hazardous voltages.
• Locate the emergency power-off (EPO) switch, disconnecting switch, or electrical outlet so that you can
turn off the power quickly in the event of an electrical accident.
• Disconnect all power before you perform a mechanical inspection, work near power supplies, or remove
or install main units.
• Before you work on the equipment, disconnect the power cord. If you cannot disconnect the power cord,
have the customer power-off the wall box that supplies power to the equipment and lock the wall box in
the off position.
• Never assume that power has been disconnected from a circuit. Check it to make sure that it has been
disconnected.
• If you have to work on equipment that has exposed electrical circuits, observe the following precautions:
– Make sure that another person who is familiar with the power-off controls is near you and is available to
turn off the power if necessary.
– When you work with powered-on electrical equipment, use only one hand. Keep the other hand in your
pocket or behind your back to avoid creating a complete circuit that could cause an electrical shock.
– When you use a tester, set the controls correctly and use the approved probe leads and accessories for
that tester.
– Stand on a suitable rubber mat to insulate you from grounds such as metal floor strips and equipment
frames.
• Use extreme care when you measure high voltages.
• To ensure proper grounding of components such as power supplies, pumps, blowers, fans, and motor
generators, do not service these components outside of their normal operating locations.
• If an electrical accident occurs, use caution, turn off the power, and send another person to get medical
aid.
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