Chapter 2 Preparing for Installation

Electrostatic Discharge

Sometimes, voltage is discharged to some of the pins of the connector and not others, or to some pins on the connector before others. This is known as a differential discharge event, which can damage the networking equipment being connected.

You can take the following measures to prevent ESD cable damage:

Ground the cable before connecting the networking equipment. You can create a grounding cable using an RJ-45 patch cable by doing the following:

Bare the wires on one end

Connect the wires to a suitable and safe earth ground

Connect the RJ-45 cable to a female RJ-45 connector

Briefly connect all cables to the grounded cable before connecting to networking equipment.

Leave cables from the networking equipment in the distribution closet connected to ports at user desktops. After you make connections on either side of the cable to networking equipment, the cable will not build up charge.

Preventing Electrostatic Discharge Damage

Electrostatic discharge (ESD) damage, which can occur when electronic cards or components are improperly handled, results in complete or intermittent failures. Port adapters and processor modules consist of printed circuit boards that are fixed in metal carriers. Electromagnetic interference (EMI) shielding and connectors are integral components of the carrier. Although the metal carrier helps to protect the board from ESD, use a preventive antistatic strap during handling.

Following are guidelines for preventing ESD damage:

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 or captive installation screws toproperly seat the bus connectors in the backplane or midplane. These devices prevent accidentalremoval, provide proper grounding for the system, and help to ensure that bus connectors areproperly seated.

 

 

Catalyst 4500 Series Switches Installation Guide

 

 

 

 

 

 

78-14409-08

 

 

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Cisco Systems 4500 manual Preventing Electrostatic Discharge Damage