Cable fault tester features and precautions for use

A high-quality cable fault tester in the cable test industry can reduce the labor intensity of workers and improve work efficiency.

The cable fault tester is composed of a transmitter and a receiver, an inductive probe, a potential difference detector, and the like. The instrument adopts electromagnetic induction method to conduct route tracing and buried depth test on the cable, and uses the potential difference method to perform fault location test on the optical cable and cable. It is suitable for the positioning test of various optical cables, cable routing, buried depth and poor grounding insulation with metal conductors (pairs, sheaths, shields). It is a dedicated tester for line faults in post and telecommunications systems and units such as military, railway, mining, oilfield, airport, and shipping.

What are the characteristics of a good cable fault tester:

First, the instrument is required to be highly intelligent. The test results can be automatically displayed on the large-screen LCD screen, which intuitively judges the fault and is equipped with a menu display operation function, without special training for the operator. It can be that they are easy to get started.

Second, it has wave-opening and parameter storage and recall functions. With non-volatile devices, waveforms and data are not lost after shutdown.

Third, it has a dual trace display function. The test waveform of the faulty cable can be compared with the normal waveform to facilitate further judgment of the fault.

Fourth, it has a waveform scaling function. Change the waveform scale and expand the waveform for accurate testing.

Fifth, control the measurement cursor, which can automatically search along the line and automatically stop at the inflection point of the fault waveform.

Sixth, the position of the double cursor can be arbitrarily changed, and the direct distance or relative distance between the fault point and the test point is directly displayed. Seventh, with a print function. Print the results of the test.

Common faults and precautions during use

1. When testing by pulse method, be careful to remove all equipment in the office and measure on the outermost line.

2. When using the flashover method test, the trigger mode switch must be placed in the “flashover” position.

3. When using the direct flash method or the flash test, pay attention to personal safety and equipment safety. The ground wire must be connected.

4. After the flashover test is completed, cut off the power supply, remove the connection line between the instrument and the high-voltage test device, and discharge the stored charge of the high-voltage capacitor and cable. When discharging, first add a current limiting resistor R to limit the discharge current to make the current slowly discharge. After the voltage on the capacitor is reduced, the resistance in the ground discharge circuit is zero, and the instantaneous discharge current can be as high as several hundred amperes, which will occur seriously. Equipment or personal accidents.

5. During the direct flash test, it is necessary to pay attention to monitoring the leakage current of the fault. If the current suddenly increases, the fault flashover phenomenon does not occur. The test voltage should be reduced immediately and the flash test should be used instead.