--9--
Miswire
– A wire or both wires of a pair are not connected to the
correct pins at the other end of the cable. In TEST mode, the wire
map shows the pin numbers
from
line 1 (main)
to
line 2 (remote).
A
reverse pair
is a special case of a miswire in which the pair is
wired to the correct pair of pins, or to another designated pair of
pins, but the two leads are reversed. In PRE-TEST, this type of
error is not detectable.
Split Pair
– A split pair is an error in the twisting of the wires
together within the cable. The cables generally are made up of 8
wires twisted together in 4 pairs. These 4 pairs are designated
as pairs by the wiring standards and are intended to carry a signal
and its return. 1 & 2, 3 & 6, 4 & 5 and 7 & 8 are the pairs desig-
nated by T568A/B for a RJ45 jack or plug. A cable can be wired
with correct continuity, but not with correct pairing. This most
often happens when the cable is terminated consistently at both
ends, but in the wrong order. A dynamic or AC test is required to
detect this type of error.
If the only error is a split pair error, the
cable has correct continuity. If cross talk is not a concern, as in
flat satin cable, the cable is good if the only error is the split pair
error.
In TEST mode, the pin numbers on the second line of the
wire map with split pairs flash, and an error message is displayed
listing the pin numbers of the pairs involved in the error. In the
PRE-TEST mode, the error message is displayed.
BATTERY REPLACEMENT
When the battery low icon is on, the battery should be replaced
as soon as practical. The cable testing results will become
unreliable when the battery reaches about 4.5 volts.
To Replace Battery
1) Remove rubber battery cap by pressing on bottom edge of
the cap with the heel of the hand until the cap pops off.
2) Pull battery out of cavity and remove battery snap.
3) Connect a new Alkaline 9 volt battery to battery snaps.
4) Slide battery into cavity and snap cap in place.
When installing a new battery,
disconnect any cables connected
to the tester.
The length and pre-test modes will be improperly
calibrated if a cable is present.
--8--
--7--
To Measure Length
1) Connect cable to main unit. (A remote may be at the other end).
2) Turn on unit by pressing any button. If not in length mode,
press MODE until LENGTH is displayed, than press SEL button.
To change length between feet and meters, use setup mode.
3) Press up and down arrows to adjust length constant. If length
constant is unknown for a particular cable, a known length
of cable may be used to set the constant. Fifty feet or more
is suggested to minimize the resolution error (1 foot in 50
is 2% uncertainty). Connect known cable to tester and set
cable constant using up and down arrows until the length
reads correctly.
INTERPETING CABLE TEST RESULTS
The PASS icon will be on if the cable has all pins properly
connected per T568A/B. The FAIL icon will be on if there is
a short or split pair. Neither icon will be on if there are opens
or miswires. The wiremap should be inspected for these types
of errors.
Definition of Errors
– (See failure example drawings) The three
classes of faults discussed below are in order of severity. The
severity has to do with the ability of a more severe error to
mask lower severity errors. For example, if there is a short in
the cable; miswires and split pairs may not be detected for the
pairs involved in the short fault.
Short
– The pair has a low resistance connection from one wire
of the pair to the other wire of the pair, or to any other wire in
the cable or the shield. A short in the TEST mode is indicated
by the FAIL icon being on and flashing Xs in the appropriate pin
position of the second line of pin numbers, plus one or more
error message lines listing all the pins shorted together. In the
PRE-TEST mode, the error messages are displayed.
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
6
6
6
6
6
6
6
6
6
7
7
7
7
7
7
7
7
7
7
8
8
8
8
8
8
8
8
8
8
T568A/B Passing Cable (unshielded)
(1 not twisted with 2; 3 not twisted with 6)
abcd
345678S
5
1
789
1 2 3 4 5 6 7 8 S ID
PASS
FAIL
CAL SETUP TEST
Short
5
78
klmnorst
ab
123456
xx
S
5
1
789
1 2 3 4 5 6 7 8 S ID
ab
13245678S
5
1
789
1 2 3 4 5 6 7 8 S ID
PASS
FAIL
CAL SETUP TEST
Split
0
1236
mnorst
ab
123
45
6
78S
5
1
789
1 2 3 4 5 6 7 8 S ID
PASS
FAIL CAL SETUP TEST
ab
12345678
45
1
789
1 2 3 4 5 6 7 8
ID
Open
Examples of Wiring Errors (Shielded)
DARK
=
ON
,
LIGHT
=
FLASHING
T568A/B Passing Cable (Unshielded)
Short
Miswire
Split Pair
