IBM 106 Hardware Installation And Maintenance Manual Download

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Preventing electrostatic discharge

To prevent electrostatic discharge (ESD) from damaging the system, be aware of the precautions to

consider when setting up the system or handling parts.
A discharge of static electricity from a finger or other conductor may damage system boards or other

static-sensitive devices. This type of damage may reduce the life expectancy of the device.

CAUTION: Parts can be damaged by electrostatic discharge. Follow these precautions:
• Avoid hand contact by transporting and storing products in static-safe containers.
• Keep electrostatic-sensitive parts in their containers until they arrive at static-protected

workstations.

• Place parts in a static-protected area before removing them from their containers.
• Avoid touching pins, leads, or circuitry.
• Always be properly grounded when touching a static-sensitive component or assembly.
• Remove clutter (plastic, vinyl, foam) from the static-protected workstation.

Grounding methods to prevent electrostatic discharge

Several methods are used for grounding. Adhere to the following precautions when handling or installing

electrostatic-sensitive parts.

CAUTION: Parts can be damaged by electrostatic discharge. Use proper anti-static protection:
• Keep the replacement CRU in the ESD bag until needed; and when removing a CRU from the

enclosure, immediately place it in the ESD bag and anti-static packaging.

• Wear an ESD wrist strap connected by a ground cord to a grounded workstation or unpainted

surface of the computer chassis. Wrist straps are flexible straps with a minimum of 1megohm (±

10percent) resistance in the ground cords. To provide proper ground, wear the strap snug

against the skin.

• If an ESD wrist strap is unavailable, touch an unpainted surface of the chassis before handling

the component.

• Use heel straps, toe straps, or boot straps at standing workstations. Wear the straps on both feet

when standing on conductive floors or dissipating floor mats.

• Use conductive field service tools.
• Use a portable field service kit with a folding static-dissipating work mat.

If you do not have any of the suggested equipment for proper grounding, have an authorized technician

install the part. For more information about static electricity or assistance with product installation,

contact technical support.

Replacing a PSU module

This section provides procedures for replacing a failed power supply unit (PSU) module.
Illustrations in PSU replacement procedures show rear panel views of the enclosure, with the PSU

properly oriented for insertion into the rear panel of the enclosure.
A single PSU is sufficient to maintain operation of the enclosure. You need not halt operations and

completely power-off the enclosure when replacing only one PSU; however, a complete orderly shutdown

is required if replacing both units simultaneously.

CAUTION: Do not remove the cover from the PSU due to danger from electric shock inside. Return

the PSU to your supplier for repair.

See CAUTION bullets regarding electrostatic discharge and anti-static protection.
Tip: The illustrations show PSU module replacement as you face the enclosure rear panel. See also Figure

4 on page 10 and Figure 7 on page 11.

68 IBM ESS expansion: Hardware Installation and Maintenance Guide - Model 106