OBJECTIVES
1. Explain the benefits of certifying cable installations.
2. Differentiate between a channel and a basic link.
3. Identify standard tests that should be performed on CAT5 cable runs
to certify them.
4. Describe the functions typically associated with cable testing
instruments.
5. Describe the steps associated with testing and certifying basic links
and channels.
Figure 6-1: Basic Link and Channel Lengths
Table 6-1: Maximum Horizontal Cable Lengths
Table 6-2: Workmanship’s Impact on Channel
Performance
TIA/EIA specifications, as outlined in TSB 67,
require that four different tests be performed
on CAT5 runs immediately after the cable is
pulled, and terminated, in order to meet the
certification guidelines and to avoid having to
troubleshoot certain types of problems later.
The four specified tests are:
the Wire Map test
the Length test
the Attenuation test
the NEXT test
Several additional tests that may be required
under certain circumstances include:
the Power Sum NEXT test
the ELFEXT test
the Power Sum ELFEXT test
the Structural Return Loss (SRL) test
the Attenuation-to-Crosstalk Ratio
(ACR) test
Figure 6-2: WireScope 155
Table 6-3: Industry Standards Performance Comparison
(Worst-Case Channel Performance @ 100 MHz)
* New requirements addressed in TSB95
Simple Rules for Testing:
NEXT test must be performed at both ends of
the run.
Documentation of test results must be included.
Cabling/components must not be moved during
testing, or retesting will be required.
End-user patch cords must be tested in place. It
is suggested that patch cords be 3 meters, but
this subject does not as yet fall into the scope of
the TIA/EIA T568A standards. It is expected
that future releases will deal with this issue.
Figure 6-3: Simple Cable Tester
The various features for this tester include:
Before and after installation checkout
Easy one-step operation
14 LEDs to confirm testing status
Shuts off automatically to maximize power
saving
Tests for shorts, connections, non-parallel
wiring, and 25/50-ohm BNC terminations
Requires a 9-volt battery
Figure 6-4: Fluke AT5 Tester
Figure 6-5: Wavetek CAT5 Tester
Figure 6-6: Microtest CAT5 Scanner and 2-Way
Injector
LAB 16 OBJECTIVE
Calibrating and Self-Testing Level II Testers
To understand the procedure for
properly calibrating the Level II
testers, performing the self test,
and documenting the test results
TIP
Several warnings are listed in the manual
that indicate the possibility of causing the
meters to give erroneous test results.
Become familiar with these error-causing
situations.
Figure 6-7: Locating the Special Functions Menu
Figure 6-8: Self Calibration Ready
Figure 6-9: Connecting the Calibration Cable
TIP
After a slight delay, during which time
the control unit reports that the selfcalibration procedure is in progress (and
various clicks and beeps can be heard),
the control unit will display the “SELF
CALIBRATION COMPLETE” message.
Figure 6-10: Message Display in the Control Unit
TIP
The screen menu returns to the SPECIAL
FUNCTIONS display. Always remember
to calibrate the Level II testers before
using them.
TIP
The Self Test function of the Level II testers
is used to check the operation of both the
control unit and the remote unit. It’s a good
idea to run this test periodically, as well.
Figure 6-11: Self Test Ready
TIP
After a slight delay, during which time
the control unit reports that the self-test
procedure is in progress (and various
clicks and beeps can be heard), the
control unit will display the “SELF TEST
PASS” message.
Figure 6-12: Display Screen for SELF TEST PASS
TIP
While the control unit is still displaying
the SPECIAL FUNCTIONS screen, it
would be a good idea to check the Battery
Status function. Because the control unit
was charged just prior to performing this
procedure, it should indicate that fact
during a check.
Figure 6-13: Display Screen for BATTERY STATUS
TIP
If the status of the battery ever drops to a
value such that the Level II testers would
not operate properly, there will be a
specific warning message displayed on
the screen.
Figure 6-14: Changing the Display to Read
NVP = 50%
Figure 6-15: Cable NVP Test Results Screen
Figure 6-16: Cable Length Test Results Screen
Figure 6-17: Changing the Display to Read
NVP = 99.9%
LAB 16 QUESTIONS
1
When should the various cables be
plugged into the Level II testers?
LAB 16 QUESTIONS
2
How long should the Level II testers
be charged, according to the users
manual?
LAB 16 QUESTIONS
3
What three measurements are
taken during a self test between the
control unit and the remote unit?
LAB 16 QUESTIONS
4
When plugging a cable into the
Level II testers, which unit (control
or remote) should be connected
first?
LAB 16 QUESTIONS
5
How long is the cable that is used
to calibrate the Level II testers?
LAB 16 QUESTIONS
6
Under what circumstances should
the Level II testers be calibrated?
LAB 16 QUESTIONS
7
How long does the self-calibration
test take to complete?
LAB 17 OBJECTIVE
Setting Up Level II Testers
To understand the procedure for
properly setting up the Level II
testers, and documenting the results
TIP
Not all of the adjustable parameters
displayed need to be tinkered with. Once
some settings have been selected, they can
normally be ignored from then on. Settings
that may require periodic changes involve
the particular test standard to be run and
the type of cable to be tested.
Figure 6-18: Page 1 of SETUP Menu
TIP
Notice that the very first parameter
displayed is the TEST STANDARD,
CABLE TYPE, because it is the
parameter that most often needs to be
adjusted.
TIP
Notice that the bottom of the display
indicates which of the four numbered
buttons to press for the desired screen.
You should now see the SELECT TEST
STANDARD screen.
TIP
You should now be looking at the
SELECT CABLE TYPE screen.
TIP
The control unit returns to the Page 1
display with the selections you just made
highlighted. Any tests conducted at this
point would expect to see CAT5 100-ohm
UTP cable connected to the Level II
testers.
TIP
This parameter allows the user to edit
the identification information that will
appear in any reports that are generated
by the Level II tester.
Figure 6-19: Edit Screen for REPORT
IDENTIFICATION
TIP
Report identification parameters that
can be edited include the CUSTOM
HEADER, the OPERATOR, and the
testing SITE. Normally, there will be
some existing text that was input from
another technician or student.
TIP
An alphanumeric listing appears, along with an edit
box for the CUSTOM HEADER, containing the
previously input text. In order to input the desired
text in the editing box, you can use the arrow keys to
select a character from the alphanumeric display.
Then, use the direction arrow button (1) to select
where the character will appear and press the
ENTER key. Alternately, you can select an existing
character position, and use the INC or DEC buttons
to move up or down the alphanumeric list to the
desired character. The Delete button (4) will delete
the character immediately to the left of the cursor.
Figure 6-20: Edit Screen for CUSTOM HEADER
TIP
The control unit returns to the
REPORT IDENTIFICATION
screen.
TIP
If you receive any message regarding the
fact that the selected parameter has been
used to generate a report, and you don’t
wish to delete the existing information,
simply press the NEW button (2) to add
another line of text.
TIP
This means that there are no temperaturedependent limits that would affect the
attenuation parameters using this cable. If
temperature was an important factor in the
use of the selected cable, you could use the
CHOICE button (1) to select an average
cable temperature that accurately reflected
the actual conditions under which this cable
was required to operate. Notice that if you
press the CHOICE button (1) at this time,
nothing happens!
Figure 6-21: Edit Screen for REMOTE END
TESTING
TIP
This setting enables you to use the
remote unit to measure NEXT and ACR
parameters from the far end of the cable
under test, provided the test standard
selected requires them. Keep in mind
that the only time the remote unit is used
is when testing twisted pair cable.
Figure 6-22: Screen for Page 2 of SETUP
TIP
Normally, when the Level II testers are
used in the field, the results of the
various tests that are conducted need to
be recorded, and printed, in order to
provide the customer and the installer
with copies.
Figure 6-23: Edit Screen for BACKLIGHT
TIME-OUT
TIP
This screen enables you to specify how long the
control unit will allow the backlight to operate
before shutting it off. Unless you were a cable
installer doing work in a dark wiring closet, there
would be no reason to operate the backlight
during normal daylight. To conserve the charged
batteries, make sure the setting shows 1 Minute.
This will turn the backlight off after the control
unit detects 1 minute of inactivity. Better yet,
conserve even more power by not pressing the
WAKE UP button at all, and keeping the
backlight off.
Figure 6-24: Edit Screen for POWER DOWN
TIME-OUT
TIP
Again, you have several timing choices
displayed. This parameter has to do with
powering down the display altogether
when the control unit detects inactivity.
This is another way that the meter
conserves its limited battery power. When
the meter shuts down the display, it
broadcasts an audible signal. The control
unit does not forget where it is when it
shuts down. To activate the unit once it
shuts down, simply press its ENTER key.
TIP
This measurement allows the monitoring of
electrical noise, on lines 3 and 6 (pair 2 for
T568A), that may be present on a twistedpair cable. The control unit samples the
voltage on the test pair once each second,
and records any noise that exceeds this
setting as a hit. For 10baseT purposes, 2 hits
within a 10-second time span is interpreted
as a failure. The default threshold for the
control unit is 270 mV, and can be adjusted
in 10m V increments.
Figure 6-25: Screen for Page 3 of SETUP
TIP
You will see settings for handling the serial
printing functions available with the control
unit. These include PRINTER TYPE,
SERIAL PORT BAUD RATE, and FLOW
CONTROL. Unless your instructor is
planning on printing out reports for your
class activities, do not change these settings.
The remaining setting on this page is for the
AUDIBLE TONE.
Figure 6-26: Screen for Page 4 of SETUP
Figure 6-27: Screen for Page 5 of SETUP
Using what you have already learned, adjust
the following settings, if necessary.
LENGTH UNITS: Feet (ft)
NUMERIC FORMAT: 00.0
LANGUAGE: English
POWER LINE FREQUENCY: 60 Hz
Figure 6-28: Screen for Page 6 of SETUP
Using what you have already learned, adjust
the following settings, if necessary.
SHIELD TEST: Enable
CONFIGURE CUSTOM CABLE: * Custom\
Cable 1 *
MAXIMUM FREQUENCY: 100 MHz
CABLE INSIDE CONDUIT: N/A
TIP
The CONFIGURE CUSTOM CABLE
setting enables the user to set up the
control unit for testing cables that
possess other than standard parameters.
You may look through the various
screens that are used to define a custom
cable, but there is no need to make any
changes to the information you see.
LAB 17 QUESTIONS
1
When does the audible tone sound
on the Level II testers?
LAB 17 QUESTIONS
2
What type of cable would you use
the remote unit to test?
LAB 17 QUESTIONS
3
What is the primary use of the
control unit’s backlight feature?
LAB 17 QUESTIONS
4
How do you reactivate a control
unit that has powered down in
order to conserve battery power?
LAB 17 QUESTIONS
5
Why would it be necessary for the
results of the various tests that are
conducted by the Level II testers
to be recorded and printed?
LAB 18 OBJECTIVE
Autotesting Patch Cables on Level II Testers
To understand the procedure for
autotesting previously created patch
cables using the Level II testers, and
documenting the results
TIP
Notice that the information provided for
the Autotest functions is divided between
those designed for twisted pair cable and
those designed for coaxial cables.
Although the tests conducted for
unshielded and shielded twisted pair are
identical, the shielded variety is also
tested for continuity along the shield.
Figure 6-29: Autotest Wiring Diagram for Jack
Terminations
TIP
Figure 4-29 displays a near minimum
configuration. A minimum configuration
would consist of only one cable. Keep in
mind that the cables could be shown
routed through a patch panel, wall plate,
or various wiring closets. One thing to
realize is that the Level II testers will not
run an Autotest on twisted pair cable,
unless a remote unit (or control unit
operating in SMART REMOTE mode) is
connected at one end of the wire run.
TIP
The idea here is to examine the wiring
condition of the cable you created in Lab 4.
Because the other two cables are known to
be good, any problems that occur should be
traced to the cable under test.
TIP
The remote unit will emit several
audible tones.
TIP
Always check to be sure that there are no
BNC cables attached to the control unit
when testing twisted pair cabling.
TIP
The control unit will emit several
audible tones.
TIP
Depending on the wiring setup and the battery
condition of the Level II testers, several things
may happen. If for some reason the connection
to the remote unit is not detected, or if the
remote’s batteries are low, you may receive a
continuous Scanning for Remote message, rather
than a very short one. In this case the Autotest
will not be run until a properly charged remote
unit is detected. Or, if a calibration message
appears on the control unit’s screen, perform the
calibration procedure presented in Lab 16.
Figure 6-30: Autotest PASS and HEADROOM Report
Screen
Figure 6-31: Autotest Test Results Screen
Figure 6-32: Wire Map Test Results Screen
TIP
All four pairs of wires are displayed, with
the various conditions of each wire
depicted. Notice that for UTP cable, the
shield wire is displayed as an open. If there
are no problems detected, the display will
appear as shown in Figure 4-32.
TIP
If the cable under test is shown to have
some type of problem, you should describe
the problem as accurately as possible on
your work sheet, and then continue
checking the rest of the test results. Once
you have finished checking the test results,
ask your instructor about correcting any
problems that were discovered with the
current cable under test.
Figure 6-33: Resistance Test Results Screen
TIP
A typical reading should be far below the
40-ohm limit. The values shown (around
0.5 ohms per pair) are fine for fairly short
cable runs. Long runs will show readings
above those values, but should still remain
below the limit.
Figure 6-34: Length Test Results Screen
TIP
The length is displayed according to the units
you selected during the setup procedure. For
longer lengths, a slight difference would be
normal between the various pairs. A typical
display for length is shown in Figure 4-34. If a
measured length exceeds the limit, a warning
is displayed.
Figure 6-35: Propagation Delay Test Results Screen
TIP
The delay time (in nanoseconds) is given
for each individual pair. In cases where a
propagation delay is detected, the display
includes the longest delay time detected of
all four pairs.
Figure 6-36: Delay Skew Test Results Screen
TIP
An important electrical characteristic of cables
with regard to high-speed computer network
performance is delay skew. This characteristic
involves the movement of electrical signals
traveling down a length of a multipair CAT5 cable,
and arriving at the far end of the cable at different
times, depending upon which twisted pair the
signals used. The difference in time taken by these
electrical signals between the fastest and slowest
wire pairs is the measurement called the delay
skew. If a computer system’s operation is
dependent on simultaneous arrival of these signals,
problems will arise at some point.
Figure 6-37: Impedance Test Results Screen
TIP
The characteristic impedance test will
require the testing of a cable of at least
16 feet (5 meters) in length. A shorter
length than this will automatically pass
the test. If the cable under test exceeds
the impedance limit specified by the
test, the Result column will display the
FAIL message. Any pair meeting the
specified limit will be given a PASS
result.
Figure 6-38: NEXT Test Results Screen
TIP
This test is concerned with the levels of
crosstalk that exist between the various wire
pairs on the cable being checked. The
measurement itself is expressed as the
amplitude difference between the test signal
and the signal being detected on another pair.
The first wire pair listed is the pair into which
the test signal is being injected, while the
second wire pair listed is the pair from which
the crosstalk is being measured. The
measurement takes place at the end of the
cable attached to the control unit.
Figure 6-39: Detailed NEXT Test Results Screen
TIP
The specific parameters reported for the selected
pair include:
Pairs – The specific pairs for which the
displayed data is relevant.
Result – The final determination as to
whether the tested wire pairs meet the NEXT
requirements for the selected test standard.
If the result shown is PASS, then the NEXT
between the tested pairs is higher than the
standard specifications. A result that reports
a FAIL indicates that the NEXT is lower than
the standard.
TIP
The specific parameters reported for the selected
pair include: (continued)
NEXT – The NEXT value that is considered
to be the worst-case measurement, or the
value nearest to failure. If the value
displayed does fall below the specification, it
will be the one that is the farthest below.
Frequency – The frequency at which the
worst-case NEXT value is measured.
Limit – For the worst-case frequency, the
lowest acceptable NEXT value.
TIP
The specific parameters reported for the selected
pair include: (continued)
Margin – The difference between the limit
and the measured NEXT value. If the
measured NEXT value is higher than the
limit, the number will be positive. If the
measured NEXT is lower than the limit, the
number will be negative.
TIP
Recall that the NEXT @ REMOTE
measurements are taken from the far
end of the cable, and are sent to the
control unit by the remote.
TIP
These test results are similar to
the NEXT data except that the
measurements are taken from
the remote cable end.
Figure 6-40: Attenuation Test Results Screen
TIP
The screen shown in Figure 4-40 provides a
basic PASS or FAIL report for each pair. The
test for attenuation is concerned primarily
with how much signal strength is lost over
the length of the cable. It is important to use
the correct conduit or temperature settings
for this measurement in order to avoid
getting erroneous results. These settings were
initially considered in Lab 17. If they need to
be changed, they can be reached from the
SETUP menu.
Figure 6-41: Detailed Attenuation Test Results Screen
TIP
The specific parameters reported for the selected
pair include:
Pairs – The specific pairs for which the
displayed data is relevant.
Result – The final determination as to
whether the tested wire pairs meet the
Attenuation requirements for the selected
test standard. If the result shown is PASS,
then the attenuation for the tested pairs is
lower than the standard specifications. A
result that reports a FAIL indicates that the
attenuation is higher than the standard.
TIP
The specific parameters reported for the selected
pair include: (continued)
Attenuation (dB) – The attenuation value
considered to be the worst-case percent
margin, at its occurring frequency.
Frequency – The frequency at which the
worst-case percent margin occurred.
Limit – For the worst-case frequency, the
highest acceptable attenuation value.
TIP
The specific parameters reported for the selected
pair include: (continued)
Margin – The difference between the limit
and the worst-case attenuation. If the
measured attenuation value is lower than
the limit, the number will be positive. If
the measured attenuation is higher than
the limit, the number will be negative.
Figure 6-42: ACR Test Results Screen
TIP
The screen shown in Figure 4-42 provides a
basic PASS or FAIL report for each pair. The
Attenuation-to-Crosstalk Ratio (ACR) is the
difference between the measured values of
NEXT, and the measured values of
attenuation, for each wire pair combination.
Obviously, the NEXT and attenuation values
(in dBs) must already have been obtained
before this parameter can be calculated.
Figure 6-43: Detailed ACR Test Results Screen
TIP
The specific parameters reported for the selected
pair include:
Pairs – The specific wire pairs from which
the crosstalk values used to calculate the
ACR were taken.
Atten. Pair – The wire pair from which the
attenuation values used to calculate the ACR
were taken.
TIP
The specific parameters reported for the selected
pair include: (continued)
Result – The final determination as to
whether the tested wire pairs meet the ACR
requirements for the selected test standard.
If the result shown is PASS, then the ACR for
the tested pairs is higher than the standard
specifications. A result that reports a FAIL
indicates that the attenuation is lower than
the standard.
TIP
The specific parameters reported for the selected
pair include: (continued)
ACR (dB) – The ACR value considered to
be the worst-case, or closest to exceeding
the specifications. If the ACR does exceed
specifications, the displayed value is the
one that exceeds the specs by the greatest
amount.
Frequency – The frequency at which the
worst-case ACR was calculated.
TIP
The specific parameters reported for the selected
pair include: (continued)
Limit – For the worst-case frequency, the
highest acceptable ACR value. The selected
test standard defines the limit.
Margin – The difference between the limit
and the worst-case ACR. If the worst-case
ACR is higher than the limit, the number
will be positive. If the worst-case ACR is
lower than the limit, the number will be
negative.
TIP
The control unit can store up to 500
AUTOTEST results. If the results are to
be saved, this must be done prior to
another AUTOTEST or SINGLE TEST
being performed.
Figure 6-44: Saving AUTOTEST Results Screen
TIP
If necessary, read the users manual section
entitled “Saving Autotest Results.” Using a
number for the ending character(s) for the
cable identification name allows the Level
II tester to automatically increment the
name, provided that the auto increment
function has been enabled. This is useful
for testing a series of identical cables.
TIP
Two conditions may exist that will require some
additional steps at this point. One of these is the
situation where saving the AUTOTEST results fills
the last remaining memory location in the Level II
tester. This will cause a warning message to be
displayed, indicating that the memory is full. The
other condition is when the Level II tester’s memory
is already full. In this situation, any attempt to save
additional test results will cause a message to be
displayed indicating that additional data cannot be
saved. At this point, previously saved test reports
must first be deleted to make room for any new ones.
Instructions for doing so can be found in the users
manual.
TIP
The only difference here is that the cable
under test will be wired for the TIA T568B
configuration. The wire map should still
indicate wire-to-wire continuity.
TIP
The idea here is to examine the
wiring condition of the cable you
created in Lab 6. Because the other
two cables are known to be good,
any problems that occur should be
traced to the cable under test.
Figure 6-45: Autotest Wiring Diagram for T568A Plug
Terminations
TIP
The idea here is to examine the wiring
condition of the cable you created in
Lab 7. Because the other two cables are
known to be good, any problems that
occur should be traced to the cable
under test. See Figure 4-46, if necessary,
and take special note of the wire map
test.
Figure 6-46: Autotest Wiring Diagram for T568B Plug
Terminations
TIP
The idea here is to examine the wiring
condition of the cable you created in
Lab 13. Because the cable you
connected to its jack end is known to
be good, any problems that occur
should be traced to the cable under
test.
Figure 6-47: Autotest Wiring Diagram for Jack/Wall
Plate Terminations
TIP
Consider the RJ45/T568A modular
plug to be the far end of the cable.
TIP
The idea here is to examine the wiring
condition of the cable you created in
Lab 14. Because the cable you
connected to its jack end is known to
be good, any problems that occur
should be traced to the cable under
test.
Figure 6-48: Autotest Wiring Diagram for
Jack/Edge-Connector Terminations
TIP
Consider the RJ45/T568A modular
plug to be the far end of the cable.
TIP
The idea here is to examine the wiring
condition of the cable you created in
Lab 9. Because this cable has already
passed the preliminary continuity
checks, any problems that occur will
be related to other cable parameters.
Figure 6-49: Autotest Wiring Diagram for RG58
Network
TIP
Figure 4-49 displays a networked
configuration connected to the Level II
tester, consisting of several computers
cabled together (with a terminator
attached to the end node). Keep in mind
that the cables could be routed through a
patch panel, wall plate, or various wiring
closets.
Figure 6-50: Single Section Coax Testing Diagram
Figure 6-51: IEEE 10Base2 Test Standard and
RG 58 Cable Type
Figure 6-52: Screen Before IEEE 10Base2 RG 58
Autotest
TIP
Never change the settings on the tester
to allow a test to pass that would fail
at the correct settings.
Figure 6-53: Autotest Results for IEEE 10Base2 RG 58
TIP
Notice that the Resistance test shows a
PASS result. If it showed a FAIL result,
this would be interpreted as an open
circuit. This is because the terminator
was removed from the far end of the
cable(s) under test.
TIP
Keep in mind that when a cable
installation is being made for a
customer, it’s important to make a
second copy of the documentation
to leave at the premises.
TIP
The NO REFLECTION report for
the Length parameter indicates a
correct terminating resistance.
With no signal reflections, the
Level II tester cannot measure the
cable’s length.
TIP
The idea here is to examine the wiring
condition of the cable you created in
Lab 11. Because this cable has already
passed the preliminary continuity
checks, any problems that occur will
be related to other cable parameters.
Figure 6-54: Single Section RG 8 Coax
Testing Diagram
TIP
Notice that this diagram is similar to
Figure 4-46, except that the N
connectors have been outfitted with
the RG8 to BNC adapters for use with
the control unit and the terminator.
Figure 6-55: IEEE 10Base5 Test Standard and RG8
Cable Type
Figure 6-56: Screen Before IEEE 10Base5 RG8
Autotest
TIP
To do this, first connect the RG8 cable
to the N side of one of the RG8 to BNC
adapters. Then, connect the BNC side
of the adapter to the Level II tester.
Figure 6-57: Autotest Results for IEEE 10Base5 RG8
TIP
Notice that the Resistance test shows
a FAIL result, and is interpreted as
an open circuit. This is because the
terminator was removed from the far
end of the cable(s) under test.
TIP
Keep in mind that when a cable
installation is being made for a
customer, it’s important to make a
second copy of the documentation
to leave at the premises.
TIP
The NO REFLECTION report for
the Length parameter indicates a
correct terminating resistance. With
no signal reflections, the Level II
tester cannot measure the cable’s
length.
LAB 18 QUESTIONS
1
From cables you made during previous
lab procedures, which, if any, failed
their respective test standards on the
Level II testers?
LAB 18 QUESTIONS
2
Of those tests performed during an
AUTOTEST, which ones are specified
by the TIA/EIA T568A or T568B
standards?
LAB 18 QUESTIONS
3
Which tests performed on twisted
pairs required the use of a smart
remote unit?
LAB 18 QUESTIONS
4
On average, how long did the Level II
testers take to provide the AUTOTEST
results for one of the CAT5 twisted pair
cables you tested?
LAB 18 QUESTIONS
5
What other cable or connector types
besides CAT5 UTP RJ45 terminations are
the Level II testers capable of testing?
LAB 18 QUESTIONS
6
What differences, if any, were evident
during the various wire map tests using
the CAT5 T568A and T568B cables?
Explain.
Figure 6-58: Basic Link Testing
Figure 6-59: Channel Testing
REVIEW QUESTIONS
1
What is a channel, as it applies to
a horizontal cable run?
REVIEW QUESTIONS
2
How is a basic link different from
a channel?
REVIEW QUESTIONS
3
Why should network cabling be tested
to a standard before the network
equipment is connected to it?
REVIEW QUESTIONS
4
What is the maximum horizontal
cable length for a basic link?
REVIEW QUESTIONS
5
How are Level I and Level II cable
testers different?
REVIEW QUESTIONS
6
State the maximum length of patch
cords that can be used when testing
a basic link.
REVIEW QUESTIONS
7
If equipment is repositioned after a
certification test has been performed,
what action must be taken?
REVIEW QUESTIONS
8
What is NEXT?
REVIEW QUESTIONS
9
What action is required if a run
passes a test with the minimum
acceptable values?
REVIEW QUESTIONS
10 How would wrapping a cable
around a 3-inch pipe affect its
NEXT performance rating?