Focus! How does a cable fault tester find low voltage cable faults? Do you know how to use the cable fault tester?

January 11, 2024

In daily power work, electric workers often encounter low resistance, high resistance, short circuit, open circuit, leakage, flashover, etc. and need to detect various cable faults. At this time, they need to use a cable fault tester, which can accurately detect the location of underground cable fault points. Location, cable length and cable buried path. So, how do we find low-voltage faulty cables with a cable fault tester? Here is a brief introduction. Low-voltage cables refer to power cables with a working voltage of less than 1kv.

Low-voltage cables are composed of wire cores, insulation layers and protective layers. They are used to connect the cables from the distribution box to the end of the equipment. Compared with high-voltage cables, low-voltage cables are richer in terms of technical structure and use.

The scope is also different, and it is also the carrier of conductive energy, and the scope of use is everywhere. The main cause of cable failure: When the cable fails, we first try to solve the failure and restore the operation. In addition, cable faults and their specific causes need to be analyzed.

There are two main reasons for low voltage cable failures. One is that external factors cause external insulation damage, and moisture causes ground faults. The second is that improper handling of the joints leads to short-circuit faults caused by moisture.

Fault finding and learning method for low-voltage cables: After a fault occurs in the cable, first use a multimeter or an electronic megohmmeter to analyze the development of current system faults in my country through research data technology. See which phase has a cable fault. After determining the faulty phase, measure the resistance to ground with a multimeter.

If we measure a resistance greater than 200 ohms, the Low Voltage Cable Fault Finding teaching method can be effectively used. Low-voltage cable fault finding method (low-voltage pulse test method): click the power button of the instrument to turn it on, there is a selection menu bar on the instrument panel when starting up, click the main menu to select the pulse menu. Then select the total length of the measurement cable, and after connecting the instrument to the cable under test, you can select the appropriate transmission speed and pulse width on the instrument according to the type of cable under test.

Adjust the connection position of the meter input amplitude potentiometer, press the meter on the sampling key to complete the sampling. During the use of high-voltage power cables, because there are many important reasons such as no external damage, moisture, etc., it will cause cable failures and seriously affect the safety management and operation of cables. It is necessary to quickly find the fault point of the cable in a short period of time in the enterprise. And learn and repair the fault point of the cable in time, and restore the power supply quickly and economically. Therefore, we need to design a cable fault tester. This article will introduce the steps of using the cable fault tester in a simple way. 1. Before on-site fault testing, check whether the power supply of the instrument is sufficient. If the power supply is insufficient, connect an external power supply to the instrument before normal use.

2. Turn on the "Power Switch". After the system is started, the instrument enters the Windows desktop system and automatically enters the cable fault test system setting interface. 3. According to the type of the cable under test, the actual length and the nature of the fault, use the stylus to click on the relevant touch keys of the cable meter to set the initial parameters.

4. After the parameter setting is completed (the default low-voltage control pulse method), connect the red and black clamps of the instrument system test line to the faulty phase of the faulty cable under test and another good phase or the cable ground wire respectively, and click the sampling button , the instrument automatically starts to enter a data information acquisition technology state, and the waveform can be studied and displayed on the screen at the same time. By clicking the sampling button again, the instrument will enter the state of continuous sampling time. The operator can continuously develop and adjust the position as well as the adjustment and amplitude as the adjustment knob according to the variation range and position relationship of the waveform displayed on different screens.

Adjust to other waveform designs for students to analyze so far, and then click the Cancel All Sampling touch key to stop using the sampling. 5. If the "high-voltage flashover mode" is set, click the "sampling" button, and the instrument will enter the "waiting for sampling" state. When the faulty cable is hit by a high-voltage flashover, the signal collected by the "sampling box" will be automatically displayed on the screen. Enter the waiting state of "sampling entry" again, and prepare to collect the next high-voltage flashover signal.

During the continuous high-voltage flashover sampling process, adjust the "displacement adjustment" and "amplitude adjustment" knobs until the waveform is easy to analyze, click the "cancel sampling" button to stop sampling, and then perform cursor operations to obtain the cable length from the fault point to the test end. The cable fault tester is a kind of equipment that is rarely used at ordinary times, but once it is used, it must be used quickly to find the fault point. It is basically inconspicuous at ordinary times, and it is very important to use, so power workers need to master it.

The above are the key points introduced by SHENZHEN NOYAFA ELECTRONIC CO., LIMITED! How does a cable fault tester find low voltage cable faults? Do you know how to use the cable fault tester? If you are still interested in related content, please continue to pay attention to SHENZHEN NOYAFA ELECTRONIC CO., LIMITED, read more related information and come here! What is the basic working principle of the cable fault tester? Which one is better? .