Klein Tools VDV501-823 - Manual (Page 5)

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VDV SCOUT ® PRO 2 OWNERS: PLEASE SKIP TO PAGE 7.
VDV SCOUT ® PRO 2 LT KEYPAD
VDV SCOUT ® PRO 2 LT – MEASURING LENGTH OVERVIEW
The VDV Scout ® Pro 2 LT uses the capacitive properties of a cable to measure its length. One end of the cable should be connected ® ®
to the corresponding port on the top of the tester. The other end should be left disconnected or attached to the self-storing remote.
The Length Constant sections below discuss the best practices to follow when measuring length in order to achieve the most
accurate results.
VDV SCOUT ® PRO 2 LT – LENGTH CONSTANT
The length constant refers to the electrical characteristic of a cable used to characterize length. Every cable has an associated length
constant in units of picofarads per foot. Setting the length constant on the tester is important to obtaining an accurate measurement
from the VDV Scout ® Pro 2 LT. The default length constants are as follows: ® ®
• Voice: 17pF/ft.
• Data: 15pF/ft.
• Video: 15pF/ft.
The length constant can sometimes be provided by the manufacturer of the cable (see EDITING LENGTH CONSTANT section). You
may have to determine the length constant yourself (see DETERMINING LENGTH CONSTANT section). Length constants can range
from 10pF/ft. to 40pF/ft.
Measurement accuracy is dependent on how close the tester can be set to the length constant of the cable being measured and the
consistency of the cable along its length.
The length constant can vary from cable to cable, even of the same type produced by the same manufacturer. It can also vary
over the length of one cable because the length constant is dependent on the physical properties of the cable, which may not be
consistent throughout the entire cable. The change in wire pair spacing through the cable can vary the length constant along the
length of the cable.
When setting the length constant using a length of cable, the cable should be at least 50 ft. long. This will yield a ±2% uncertainty (1
in 50) of length constant accuracy. A longer cable reduces this uncertainty.
VDV SCOUT ® PRO 2 LT – MEASURING LENGTH
F. Voice/Up Arrow: In Length Measurement mode, press and
release to measure length of a cable connected to the RJ11/12
port. Press and release again to change which pair of wires
length is being measured on. By default, the VDV Scout ® Pro ® ®
2 LT will test for length on the first pair with no faults found. In
Length Constant Edit mode, this button will increase the length
constant by 0.1pF. Hold down to scroll through values quickly.
G. Video/Down Arrow: In Length Measurement mode, press
and release to measure length of a cable connected to the
F-connector port. In Length Constant Edit mode, this button
will decrease the length constant by 0.1pF. Hold down to scroll
through values quickly.
H. Data: In Length Measurement mode, press and release to measure length of a cable connected to the RJ45 port. Press and
release again to change which pair of wires length is being measured on. By default, the VDV Scout ® Pro 2 LT will test for ® ®
length on the first pair with no faults found.
I. Tone/Length Measurement: While the tester is off, press and hold for three seconds to enter Tone mode (see general Keypad
section). While the tester is off, press and release to enter Length Measurement mode. In Length Measurement mode, press
and release again to briefly show the length constant. Press and hold for three seconds to enter Length Constant Edit mode.
Press and release the button one more time to exit Length Constant Edit mode.
I
F G H
ID
1. Connect one end of the cable under test to the RJ45 port (if you are testing an
Ethernet cable) or RJ12 port (if you are testing a phone cable) or F-connector port
(if you are testing a coax cable) located at the top of the main tester body. Leave the
other end of the cable unterminated.
2. Press the length button I to enter length mode.
3. Press the data button H or the phone button or the phone button F or the video button or the video button G on on
the keypad to begin the test on the Ethernet cable or phone cable or coax cable,
respectively.
4. (Optional) press H or or F repeatedly to select the pair of wires repeatedly to select the pair of wires that should be
measured. The first pair that is functional is chosen by default.
5. Read the length measurement as shown.
Note: A phone or data cable under test can be unterminated (open) or terminated by an
RJ45 ID remote. If it is terminated by the self-storing remote, the reading will be 1
or 2 ft. greater than the actual measurement. In this case, subtract 1 or 2 ft. from
the reading to obtain the actual measurement. Coax cable under test must be left.
unterminated. Coax ID remotes cannot be used.