Multitech RF500S Uživatelský manuál stáhnout pdf (Strana 20)

6.1.5 568A and 568B Pinnout

A cause of much confusion when implementing structured wiring is the fact that two different connector

pinnouts were defined T568A and T568B.

They are nearly identical except pair 2 and 3 are swapped. Electrically this is of no consequence as long as

both ends use the same pinnout. When wiring a premise pick one version and use it through.

6.1.6 Patch Cables

Patch cable are used to connect devices to wall jack. Normally patch cables are purchased ready made. The

pinnout version of patch cables can be ignored since the vendor terminated both ends the choice of pair

color does not matter.

Patch cables come in two versions, straight through and crossover. Straight through cables are used in

almost all circumstances. Connecting computer to wall jack and to computer to hubs. UTP Ethernet uses a

point-to-point wiring scheme. The transmit port of the computer connects to the receive port of the hub, and

vice versa. If this default arrangement cannot be used, for example connecting two computers directly

together you need to use a crossover cable. This type of cable swaps the transmit and receive pair at one

end of the cable so like devices can be directly connected.

6.1.7 Special Tools

Proper tooling is absolutely essential to produce a reliable network. Do not attempt to install and terminate

network wiring without proper tools

Tool

Purpose

Wire Cutters

Cut Cable to length

Cable Stripper

Special Stripper to remove the outer cable jacket

Punchdown Tool

Terminate 66 and 110 blocks

110 Blade

Terminate 110 blocks

66 blade

Terminate 66 blocks

Crimper

Crimps wires into Plug

Fish tape

Used to snake wire through walls

A good wiring guide is the “Technician’s Handbook -- Communications Cabling” by James Abruzzino

ISBN 0-9671630-0-5.

Cabling should be tested after installation; simple testers are in the $100 range making them somewhat

expensive for small installation. An ohmmeter will verify end-to-end continuity. This finds many common

errors however it will not find split pairs. This is where end-to-end continuity exists but the pairing is

incorrect. This type of mistake may work with 10Mbps but will fail at 100. The other concern is excessive

untwisted length. When terminating the wire it is important to untwist only enough wire to make the

connection and no more.

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Multitech RF500S Uživatelský manuál Strana 20