700 Series Managed Switch User’s Guide for Software v2.1

Table-B-1. Electrical Requirements of Category 5 Cable

SPECIFICATIONS

CATEGORY 5 CABLE REQUIREMENTS

Number of pairs

Four

 

 

 

Impedance

100 ± 15%

 

 

Mutual capacitance at 1 KHz

5.6 nF per 100 m

 

 

Maximum attenuation

at 4 MHz: 8.2

(dB per 100 m, at 20° C)

at 31

MHz: 11.7

 

at 100 MHz: 22.0

 

 

 

NEXT loss (dB minimum)

at 16

MHz: 44

 

at 31

MHz: 39

 

at 100 MHz: 32

 

 

 

Twisted Pair Cables

For two devices to communicate, the transmitter of each device must be connected to the receiver of the other device. The crossover function is usually implemented internally as part of the circuitry in the device. Computers and workstation adapter cards are usually media-dependent interface ports, called MDI or uplink ports. Most repeaters and switch ports are configured as media-dependent interfaces with built-in crossover ports, called MDI-X or normal ports. Auto Uplink technology automatically senses which connection, MDI or MDI-X, is needed and makes the right connection.

Figure B-1illustrates straight-through twisted pair cable.

Figure B-1: Straight-Through Twisted-Pair Cable

Cabling Guidelines

B-3

SM-10004-02

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NETGEAR 700 Series manual Twisted Pair Cables, Specifications Category 5 Cable Requirements