Cisco Systems 4900M manual Grounding Requirements, EMI Recommendations

Models: 4900M

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Chapter 2 Site Planning

Grounding Requirements

EMI Recommendations

Follow these guidelines when setting up the site wiring. When planning the location of the new system, consider electromagnetic interface (EMI), the distance limitations for signaling, and connector compatibility.

When wires are run for any significant distance in an electromagnetic field, radio frequency interference (RFI) can occur between the field and the signals on the wires.

Bad plant wiring can result in radio frequency interference.

Strong EMI, especially when caused by lightning or radio transmitters, can destroy the signal drivers and receivers in the switch and can create an electrical hazard by conducting power surges through lines and into equipment.

Note To predict and remedy strong EMI, you might need to consult RFI experts.

Power Requirements and Heat Dissipation

The power requirements might be useful for planning the power distribution system needed to support the switches. Heat dissipation is an important consideration for sizing the air-conditioning requirements for an installation. Refer to Appendix A, “Specifications,” for the power and heat ratings for a Catalyst 4900M switch.

Grounding Requirements

Grounding is recommended on all AC or DC installations, using only approved copper connectors. Attach the provided two hole ground lug to the chassis using M4x 8mm bolts and then to the central office (CO) or other interior ground system with number 6 AWG wire. The grounding connector is on the rear of the chassis, as shown in Figure 2-1.

 

Cisco Catalyst 4900M Switch Installation Guide

2-4

78-18350-01

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Cisco Systems 4900M manual Grounding Requirements, EMI Recommendations, Power Requirements and Heat Dissipation