Lab 5.3.5 Cable Tester - Wire Map

Estimated time: 45 min.

Objectives:

- Demonstrate skill with a cable tester more advanced than a simple continuity/pin-out tester
- Use the wire mapping features of the tester to check for opens and shorts with UTP cable
- Perform wire mapping on cables, detecting faults that are not detectable with simple continuity measuring devices such as crossed and split pairs

Background:

> In this lab you will learn the wire mapping features of the Fluke 620 LAN CableMeter (or its equivalent). Wire maps can be very helpful in troubleshooting cabling problems with UTP cable. Wire maps are not used with coaxial cable since there is only one wired and no map is needed. A wire map allows the network technician to verify which pins on one end of the cable are connected to which pins on the other end. With an understanding of the proper wiring connections, you can determine when a cable is wired improperly, depending on its intended use. You will learn how to use a cable tester to check for the proper installation of Unshielded Twisted Pair (UTP) Category 5 (CAT 5) according to TIA/EIA-568 cabling standards in an Ethernet network. You will test different cables using all four pairs to determine some problems that can occur from incorrect cabling installation and termination.

> The cabling infrastructure (or cable plant) in a building is expected to last at least 10 years. Cabling related problems are one of the most common causes of network failure. The quality of cabling components used, the routing and installation of the cable and quality of the connector terminations will be the main factors in determining how trouble-free the cabling will be.

Tools / Preparation:

> Prior to starting the lab, the teacher or lab assistant should have several correctly wired CAT 5 cables (both straight thru and crossover) to test. There should also be several CAT 5 cables created with problems such as poor connections and split pairs to test. Cables should be numbered to simplify the testing process and to maintain consistency. A cable tester should be available that can test at least continuity, cable length and wire map. Work individually or in teams. The following resources will be required:

> - CAT 5 straight-wired cables of different colors.
> - CAT 5 crossover-wired cable (T568A on one end and T568B on the other )
> - CAT 5 straight-wired cables with open wire connections in the middle or one or more conductors shorted at one end of different colors and different lengths.
> - CAT 5 straight-wired cable with a split pair mis-wire.
> - Cable Tester (Fluke 620 LAN CableMeter or similar) to test cable length, continuity, wire map

Related Research Web Sites

:

> - http://www.bicsi.org/techsem
> - http://www.fluke.com/

Step 1 - Set the Advanced Cable Tester for the Desired Cable.

These instructions pertain to the Fluke 620 LAN CableMeter. Turn the rotary switch selector on the tester to the WIRE MAP position. Press the SETUP button to enter the setup mode and observe the LCD screen on the tester. The first option should be CABLE: Press the UP or DOWN buttons until the desired cable type of UTP is selected. Press ENTER to accept that setting and go to the next one. Continue pressing the UP/DOWN arrows and pressing ENTER until the tester is set to the following cabling characteristics.

Tester Option | Desired Setting
CABLE: | UTP
WIRING: | 10BASE-T or EIA/TIA 4PR
CATEGORY: | CAT 5
WIRE SIZE | AWG 24
CAL to CABLE? | NO
BEEPING: | ON or OFF
LCD CONTRAST | From 1 thru 10 (brightest)

Step 2. Setup the Cable to be Tested

> For each cable to be tested use the following procedure, place the near end of the cable into the RJ-45 jack labeled UTP/FTP on the tester. Place the RJ-45-RJ-45 female coupler on the far end of the cable and then insert the Cable Identifier into the other side of the coupler. The coupler and the cable identifier are accessories that come with the Fluke 620 LAN CableMeter.

Step 3 – Perform Wire Map Testing

> Using the tester Wire Map function and a Cable ID Unit, you can determine the wiring of both the near and far end of the cable. The top set of numbers displayed on the LCD screen is the near end and the bottom set is the far end. Perform a Wire Map test on each of the cables provided and fill in the following table based on the result for each CAT 5 cable tested. For each cable, write down the number and color, whether the cable is straight thru or crossover, the tester screen test results and what you think the problem is.

> Cable No. | Cable Color | How cable is wired (straight-thru or crossover) | Tester Displayed Test Results (Note: refer to the Fluke manual for detailed description of test results for wire map) | Problem Description

1 |  |  | Top: Bot: |
2 |  |  | Top: Bot: |
3 |  |  | Top: Bot: |
4 |  |  | Top: Bot: |
5 |  |  | Top: Bot: |