Cisco Catalyst 9600 Series, Руководство по установке оборудования

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Preventing Electrostatic Discharge Damage
Electrostatic discharge (ESD) damage may occur when modules or other FRUs are improperly handled, and
result in intermittent or complete failure of the modules or FRUs. Modules consist of printed circuit boards
that are fixed in metal carriers. EMI shielding and connectors are integral components of a carrier. Although
the metal carrier helps to protect the board from ESD, always use an ESD-grounding strap when handling
modules. To prevent ESD damage, follow these guidelines:
• Always use an ESD wrist or ankle strap and ensure that it makes good skin contact.
• Connect the equipment end of the strap to an unfinished chassis surface.
• When installing a component, use any available ejector levers to properly seat the bus connectors in the
backplane or midplane. These devices prevent accidental removal, provide proper grounding for the
system, and help to ensure that bus connectors are properly seated.
• When removing a component, use any available ejector levers to release the bus connectors from the
backplane or midplane.
• Handle carriers by available handles or edges only; avoid touching the printed circuit boards or connectors.
• Place a removed component board-side-up on an antistatic surface or in a static shielding container. If
you plan to return the component to the factory, immediately place it in a static shielding container.
• Avoid contact between the printed circuit boards and clothing. The wrist strap only protects components
from ESD voltages on the body; ESD voltages on clothing can still cause damage.
• Never attempt to remove the printed circuit board from the metal carrier.
Power Requirements
Power supplies installed on the switch chassis can be all AC-input, all DC-input, or a mix of both. When
preparing your site for switch installation, adhere to these requirements:
• In systems configured with more than one power supply, connect each of the power supplies to a separate
input power source. If you fail to do this, your system might be susceptible to total power failure due to
a fault in the external wiring or a tripped circuit breaker
• To prevent loss of input power, be sure that the total maximum load on each source circuit is within the
current ratings of the wiring and breakers.
• In some systems, you may decide to use an uninterrupted power supply (UPS) to protect against power
failures at your site. Be aware when selecting a UPS that some UPS models that use ferroresonant
technology may become unstable when operating with the switch power supplies that use power factor
correction. This may cause the output voltage waveform to the switch to become distorted, resulting in
an undervoltage situation in the system.
Cabling Requirements
When running power and data cables together in overhead cable trays or subfloor cable trays, be aware of the
following caution:
Cisco Catalyst 9600 Series Switches Hardware Installation Guide
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Preparing for Installation
Preventing Electrostatic Discharge Damage