Manual Fluke networks TS 100 Cable Fault Finder (page 15 of 20) (English)

624062

Zoom out

Zoom in

1/20

Time Domain Reflectometry (TDR) Technology

The actual formula used is as follows: The time is divided by two because the signal traveled

the length of the cable twice. Once when it left the

tester and went to the failure point, and again when it

reflected back to the tester to be detected. The speed

of light expressed in billionths of a second per foot is

0.9835 (about a billion feet per second) (0.2998 [about

300 million meters per second]).

bfz04.eps

Figure 4. TDR Waveform

VOP Variations

This characteristic speed of the signal for a particular

cable is not normally a tightly controlled part of the

cable manufacturing process and can vary widely from

one manufacturer to another as well as from one box

of cable to the next. As with all TDR-based cable

measurement tools, the TS100 measures TIME within

specified tolerances, but the displayed LENGTH is the

result of the calculation with the user-selected VOP and

is only as accurate as that selected VOP.

For most uses, a length reading with an incorrectly set

VOP is sufficiently accurate to locate the fault in the

cable. After all, an installed cable is hardly ever run in a

straight line. It can be stapled along the 2x4, laid

diagonally in the ceiling, and coiled behind the

junction box, all of which is not visible.

Also, common sense should prevail. For example, if the

tester reports an open at 80 feet (25 meters), and you

can see a junction box at about 70 feet (20 meters),

your first step should be to check at the junction box.

However, for some uses such as measuring the

remaining cable in a box, it is important to set the VOP

correctly in order to achieve the accuracy desired.

Depending on the cable construction (shielded,

twisted, etc.), insulating material (foam, air, fiber, etc.),

and conductors tested (wire-to-wire, wire-to-shield),

coiling the cable on a spool or in a box may alter its

VOP.

Additionally, other conductors in close proximity to the

conductors being tested can affect the VOP. For

example, a solitary 12 gauge THHN in a metal conduit

has a VOP of 82, while that same wire in a smaller

conduit filled with other wires has a VOP of 72.

0.98352

Length= Time in billionths of a second

VOP

Report abuse

Libble takes abuse of its services very seriously. We're committed to dealing with such abuse according to the laws in your country of residence. When you submit a report, we'll investigate it and take the appropriate action. We'll get back to you only if we require additional details or have more information to share.

Product:

Forumrules

To achieve meaningful questions, we apply the following rules:

First, read the manual;
Check if your question has been asked previously;
Try to ask your question as clearly as possible;
Did you already try to solve the problem? Please mention this;
Is your problem solved by a visitor then let him/her know in this forum;
To give a response to a question or answer, do not use this form but click on the button 'reply to this question';
Your question will be posted here and emailed to our subscribers. Therefore, avoid filling in personal details.

new questions and answers
new manuals

You will receive an email to register for one or both of the options.

Get your user manual by e-mail

Enter your email address to receive the manual of Fluke networks TS 100 Cable Fault Finder in the language / languages: English as an attachment in your email.

The manual is 0,55 mb in size.

You will receive the manual in your email within minutes. If you have not received an email, then probably have entered the wrong email address or your mailbox is too full. In addition, it may be that your ISP may have a maximum size for emails to receive.

The manual is sent by email. Check your email

If you have not received an email with the manual within fifteen minutes, it may be that you have a entered a wrong email address or that your ISP has set a maximum size to receive email that is smaller than the size of the manual.

The email address you have provided is not correct.

Please check the email address and correct it.

Your question is posted on this page

Would you like to receive an email when new answers and questions are posted? Please enter your email address.

Info

Fluke networks TS 100 Cable Fault Finder Manual

Product: