Time Domain Reflectometers – All You Should Know About Its Working
Posted by freddy kent on May 10th, 2021
A time-domain reflectometer is a sort of device which is certainly used to detect the location of faults in transmission lines and other coaxial cables. They are used for testing cable systems and other forms of the feeder, where they are able to detect and pinpoint a variety of issues. Due to its name, people tend to get confused about time domain reflectometers and how it works. These time domain reflectometers are widely used in any area where there may be long or inaccessible lengths of cable that require to be tested, or they may have faults.
TDRs are considered a safe tool for operators in a variety of applications. A TDR is a particularly valuable tool in specific locations that are difficult to reach. For example – After the Deepwater Horizon Oil Spill of 2010, scientists, with the help of robots, aided the cleanup efforts. These engineered submarines were attached to long and lengthy cables, which sometimes extended deep in the ocean. Also, technicians used TDR’s to successfully identify cable faults, even though cables were extended for up to thousands of feet into the ocean.
Some applications of Time Domain Reflectometers:
1. Telephone Cable Landlines – TDRs are considered a highly valuable tool for telecommunication field engineers who are required to repair telephone and broadband lines. They can be used for testing very long cable runs, where there seems impossible to dig up and remove the kilometers-long cable. Even if breakage occurs, TDRs can locate their position with considerable accuracy.
2. Circuit Board Testing – Some specialized time domain reflectometers can also be used for failure detection of modern high frequency printed circuit boards, especially on tracks usually designed to emulate transmission lines. The reflections noticed by the TDR help in revealing any unsoldered part of the array device or even short-circuited pins.
3. Industrial Applications – Time Domain Reflectometers are also used in a wide variety of industrial applications, such as testing of integrated circuit packages where failing areas of an IC can be well detected. This technology of TDR is also known to be in good usage for measuring liquid levels.
4. Landline Security Surveillance – TDRs can also help detect the existence and location of wiretaps. The wiretaps tend to introduce a slight change in the impedance of the line, and this event can be measured on the TDR when connected to a phone line.
Summary – Even a slight change in the impedance tends to cause either a positive or negative reflection. It all depends on whether the conductors go apart or get close together. The TDR helps translate these reflections to traces, which the operator can interpret to indicate a particular set of events such as opens, shorts, or splices present in the cable held under test.
Author’s Bio – The author is an engineer and a blogger. This article deals in the importance of Time Domain Reflectometers along with its applications.
