Interface speed local pair pair length remote pair pair status.
Tdr cable test open.
Testing category 5 utp cable.
Tdr time domain reflectometer network analysis cable test first line repair handheld cable test fault finders are designed for first line repair and less specialised field operatives where the requirement is accurate and consistent fault location on the most common types of field problems such as open and short circuits.
It can be used to characterize and locate faults in metallic cables for example twisted pair wire or coaxial cable.
The pair length can be displayed in meters m centimeters cm or kilometers km.
To display the results of the cable analysis enter a command such as the one shown in the following examples at the privileged exec level of the cli.
Basic tdr operation application note 58 velocity factor to operate a tdr it is necessary to tell the tdr the speed of the pulse in the cable.
Hence for an open end z z 0 and r is a positive reflection.
Is it at the closet end or user end.
How do i pinpoint at which end the pair is open.
The time domain reflectometry tdr.
In the event of an open or shorted cable the accuracy of length of where the cable is open or shorted is plus or minus 2 meters.
This can be determined by testing a known length of the cable under test and leaving the remote end open.
Set up the cable analyzer to test cat 5 utp basic link and select the tdr test mode.
I have this output from a cable diagnostic test that i did.
A tdr sends a low voltage pulse into the cable under test and at any impedance change within the cable a reflection will be seen.
This enables the tdr to convert the time the reflected pulses take into distance.
It can also be used to locate discontinuities in a connector printed circuit board or any other electrical path.
Show cable diagnostics tdr int f0 39.
In the first example the command displays tdr test results for port 1 slot 1 on device 1 in the stack.
The tdr measures the time between release and return of the low voltage pulse from any reflections.
If the tdr test has not been run on the port the following message is displayed.
Sw 01 test cable diagnostics tdr interface g1 0 5 link state may be affected during tdr test tdr test started on interface gi1 0 5 a tdr test can take a few seconds to run on an interface use show cable diagnostics tdr to read the tdr results.
Tdr test was never run on gi2 12 examples this.
Not only is it possible for the time domain reflectometer to discover where the fault or problem has occurred along the cable it is also possible to discover much about the nature of it as well.
The results indicate that the port is down or the cable is not connected.
Tdr test last run on.
Plug in the connectorized distribution end of any cat 5 utp cable pulled dark and press the analyzer s test button.
A time domain reflectometer tdr is an electronic instrument used to determine the characteristics of electrical lines by observing reflected waveforms.
