Fluke TS 100 PRO User Manual page 22

TS100 PRO Cable Fault Finder
Users Guide
Q: Why, on some cables, does the number displayed
jump between 2 or 3 different values?
A: As the TDR signal travels down a cable, it loses some
of its strength. At some point, the noise on the cable
has an amplitude similar to the reduced strength TDR
signal and will influence the measurement results. The
tester's software filters out many of the noise related
variations in the displayed length, but some variations
do get through.
Q: I accidentally cracked the plastic housing, does this
affect the moisture protection of the components?
A: Not at all. The component protection is provided by
a coating on the components and Printed Circuit Board
(PCB).
However, if sufficient plastic is missing then a possible
shock hazard exists. You should not use the tester until
the plastic is repaired or replaced.
Q: Can this tester measure the length of single
conductor wires like THHN?
A: No. All TS100 PRO measurements must be made on
TWO conductors from the same end of a cable.
Q: If I touch the bare metal of the wires or clip leads,
will the measurement be affected?
A: After BOTH clips are connected, measurement
results will ordinarily not be affected if you accidentally
touch the input connectors. If a large surface area of
cable touches moist skin, some readings may be
affected.
Q: On multi-conductor cables with a short between
two of the conductors, I sometimes read an "open" at
twice the known length of the cable.
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A: If the cable has more than two conductors, and a
short exists at the far end between one of the
conductors you are connected to and a conductor you
are not connected to, the displayed length will be the
sum of the lengths of the conductors joined by the
short. The TS100 PRO can only correctly test the two
conductors that are connected to the tester. See
"Applications" on page 10 for multi-conductor cables.
Q: When testing a set of wires that go into a conduit, I
sometimes get a reading of 0 or 1. Why?
A: If there is more than a foot or so of wires that are
physically separated before they enter the close
confinement of the conduit, this will look to the tester
like an open at the start of the cable. Remember that
TS100 PRO reports the first failure that it finds. Try
bringing the two wires of the pair closer together for
the section from the tester to the entrance of the
conduit.
Q: When connecting to a 6 foot (2 meter) piece of 50
Coax with the alligator clips, the tester reads 8 feet (3
meters). What's up?
A: When measuring a low impedance small cable (less
than 15 feet [5 meters]), the clip leads can add up to 2
feet (1 meter) of length. For longer or high impedance
cables, the clip leads have no effect.
Q: How does the tester react to a speaker or a
transformer at the end of a cable?
A: A speaker or a transformer is actually a large coil of
wire. This will usually cause the length reading to be
larger than that of the cable alone. A moderate power
speaker will add 500 feet (150 meters) to the length
reading. Some combinations of speakers and
transformers connected to the cable may prevent the
tester from making a valid reading.