Since the buried cable appears in our lives, cable fault detection has become a test person. How to accurately find cable fault points through layer soil, need not only the experience of maintenance personnel, but also requires corresponding equipment support. Since the buried cable appears in our lives, cable fault detection has become a test person.
How to accurately find cable fault points through layer soil, need not only the experience of maintenance personnel, but also requires corresponding equipment support. Cable fault tester is one of the commonly used detection devices. We today mainly explore what is the difference between low-voltage cable fault tester and tradition.
Differential analysis of low-voltage cable fault testers and traditional cable fault testers: 1. Description of the fixed-point method of cable faults. Cable faults have two types of bridge method and pulse anti-shooting. There are several types of cable faults: 1. Sound test: The sound test is used, which is from the past to the future, universally adopted cable failure design. And it is the most effective way.
However, the instrument used from the past has developed into a commonly used sound synchronization setpoint instrument. The sound test is suitable for high voltage cables, low voltage cables, direct buried cables, cable trench cables, etc. 2, step voltage method: adopt steppoint voltage status, mainly for external protection socket faults for the insulation of cable outer sheath, now the partially buried non-armored low-voltage cable, wire ground fault, also Step voltage status can be used.
3, electromagnetic method and audio method: use electromagnetic wave or adopt audio statutory point, from principle. But from the current situation, there is no fixed-point meter that can be reliable and can actually apply. Alternatively, the fixed-point meter with electromagnetic wave is still in research and development of various research institutions, and further verification is further validated in practice to achieve the actual application level.
Second, the medium and low-voltage cable detector (bridge tester) introduction: The medium and low-voltage cable detector circulating on the market is now the end of the cable fault. The principles generally use the bridge method, but it has now been used in computer technology, which uses a smart bridge. There are low-voltage bridges, high-voltage bridges, and more.
Some instruments have also adopted the principle of ultra-high voltage digital bridge. The voltage added to the fault point is generally more than 200V, and the most GAO can be added to 20kV. Lower fault resistance (less than 600m resistance)Ω) Cable fault.
The mid-pressure cable detector can be roughly tested. Application range: It is suitable for leak failure tests with high fault resistance. Generally used for cable fault testing of 6000V or less<Fault distance rough test>.
Advantages: For cable faults that adapt to tests, it is simple to use, and the technical requirements for users are not high. which is“fool”Test. In addition, for some fault points, if some cable connectors are faulty, due to the long climbing distance, it cannot be formed.“Flashover”The failure of discharge, since the pulse method is crude, and the bridge method has its superiority.
In the actual test, the insulation resistance of the fault point is less than 100m, but the high-pressure flashing test (the impact voltage is greater than 20kV), the low-pressure discharge current displayed by the operating box does not exceed 5A, the sound of the ball is discharged, and the sound point is not Forming a flashing discharge, the flash test is shown as a full length waveform of the cable. In this case, we can basically become faulty. It can be excavated directly to the intermediate head, and accurately diagnose the fault point with cable fault design.
The above is the difference between the medium and low-voltage cable fault tester and the traditional tester. Do you understand? For more information, please continue to pay attention to Xiaobian.
Copyright © 2022 SHENZHEN NOYAFA ELECTRONIC CO.,LIMITED - www.noyafa.net All Rights Reserved.