Time domain reflectometers are tools that can help make cable troubleshooting faster and easier. Instead of spending time and effort finding faults manually, these devices can localize the fault within seconds. These testers are especially valuable on cable installations that are several miles long. They are not only suitable for cable fault location in electrical systems but also in telecommunications, television and computer network facilities.
A time domain reflectometer works like a radar in finding cable defects. The device sends out a test pulse through the conductor of the test sample and at the same time, triggers a timer. If the pulse encounters a fault, part of the pulse is reflected back to the tester. As soon as the echo is received by the tester, the timer is stopped. Since the propagation of electrical waves is constant, the round trip time of the echo can be used to compute the distance to the fault.
With the number of cable fault locators on the market today, selecting the most suitable tester can be confusing. There isn't the "best of the best" or a "one-size-fits-all" tester. You must determine the features you need and the the tester that is most appropriate for the application. Just imagine getting a meter with all the bells and whistles, and then only using a very small fraction of its capabilities. That would be a waste of money and you will not be maximizing the full potential of the device.
Megger CFL510F Hand-held Time Domain Reflectometer can be used on any cable consisting of at least two insulated metallic elements, one of which may be the sheath or shield of the cable. The CFL510F has internal matching networks to allow testing of 25-, 50-, 75- and 100-ohm cables. (These correspond to power, cellular, CATV, and telephone cable).
The FastFind key simplifies waveform interpretation by automatically adjusting the instrument's range and gain and places the measurement cursor at the major event on the cable.
The Megger CFL510G Hand-held Time Domain Reflectometer is a hand held, compact Time Domain Reflectometer for locating faults on metallic cables. It has a minimum resolution of 0.1 m/0.3 ft and a 5 km/15,000 ft maximum range depending on velocity factor selected and cable type.
Four output impedances (25, 50, 75, and 100 Ω) are available and a velocity factor between 0.2 and 0.99 will meet any cable test requirements.
The Megger CFL510G has a simple selection option which, together with a four-way control switch, offers an intuitive operation for the user.
The Megger CFL535G Advanced Dual Channel TDR is a state of the art, dual channel, high resolution, compact Time Domain Reflectometer with a color screen for locating faults on paired metallic cables.
The CFL535G has a minimum resolution of 0.3 ft /0.1 m and a 60 kft/20 km maximum range depending on the velocity factor for the cable type being tested.
Five output impedances are available (25, 50, 75, 100, 125 ohms) and an auto impedance matching feature.
The velocity factor can be set between 0.2 and 0.99 to meet any cable test requirements.
- 600 V CAT IV input protection filter built in (Model TDR2050)
- Step and pulse TDR selections
- Distance dependent gain
- Test straight from the box
- Trace tagging
- 2ns pulse width
- Designed for use on all metallic paired cables
Related electrical test equipment available for rent from Protec:
Editor’s Note: This post was originally published on May, 2012 and has been updated freshness, accuracy and comprehensiveness.