Portable grounding resistance tester

Abstract

The invention discloses a portable grounding resistance tester, which includes a voltage transformer and a current transformer that are disposed on a pole grounding down lead, a first single-chip microcomputer module, a first signal generation module, a first amplitude adjusting module, a voltage output module, a first current acquisition module and an AC constant current source module. The first single-chip microcomputer module is connected to the first signal generation module and the first current acquisition module. The first signal generation module, the first amplitude adjusting module and the voltage output module are connected in order. The voltage output module is connected to the voltage transformer. The first current acquisition module is connected to the current transformer. The AC constant current source module is used for correcting the output current of the current transformer. The beneficial effects of the tester are that the grounding resistance of a pole with down leads can be measured through the transformers and a signal processing technique while the leads do not need to be detached, and the problems of high labor intensity and complex process of a conventional measuring method are solved.

Description

technical field [0001] The invention relates to the technical field of ground resistance measurement, in particular to a portable ground resistance test applied to power transmission line towers. Background technique [0002] The grounding resistance tester is a new type of digital grounding machine that abandons the traditional manual power generation method, adopts advanced large-scale integrated circuits, and uses DC / AC conversion technology to combine the three-terminal button and four-terminal button measurement methods into one model. Resistance tester. It is suitable for measuring the grounding resistance of various devices and measuring the resistance value of low-resistance conductors in departments such as electric power, post and telecommunications, railways, communications, and mines. [0003] Two kinds of ground resistance testers commonly used at present include: ZC-8 ground resistance tester and clamp ground resistance tester. [0004] ZC-8 type grounding re...

AI Technical Summary

Problems solved by technology

[0007] 1) Generally, there are four down-conductors on the tower of the transmission line. Before the measurement, all the down-conductors need to be untied, and a wire of more than ten meters or even tens of meters should be laid to connect to the auxiliary ground. The workload is heavy and the labor intensity is high. cumbersome process

When working in winter, due to the low temperature, the wire sheath of the wire becomes brittle and easy to break

In addition, the measurement results have a lot to do with the skill level and sense of responsibility of the inspectors. If the voltage poles and current poles are not correctly arranged during the operation, there will often be large errors in the results.

[0008] 2) It is dangerous to untie the grounding down-conductor. For the place where a fault occurs, the instantaneous current flowing through the grounding down-conductor can reach 13.7A. When the last grounding down-conductor is untied, there will be Electric sparks are generated and accompanied by burning phenomenon

[0010] 4) When measuring in mountainous areas, due to high soil resistivity, long ground radiation extension line, complex terrain, etc., the electrodes of the shaker cannot be arranged according to the regulations.

In addition, the different configuration methods of the transmission line and the clamp meter measurement frequency may have a certain impact on the measurement results of the clamp meter method.

[0012] 6) Due to the different on-site environments (temperature, humidity, electromagnetic environment), certain errors will be caused to the measurement results. If no self-test is performed before the measurement, the measurement results will have a large error

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