A grounding resistance monitor with self-test and calibration

Abstract

The invention discloses a grounding resistance monitoring instrument with self-checking and correction, which comprises a main circuit and a switching circuit connected with the main circuit, and the switching circuit is respectively connected to an external grounding network and a standard resistance. Add a high-precision standard resistance to the circuit board to simulate the ground network, and transfer the circuit that originally tested the external ground network to the standard resistance on the test board through the relay switching circuit. Fine-tuning is implemented inside the program, and the offset is added to the measured value to reach the normal value; if there is a large deviation between the measured value and the standard value, it means that there is a big problem with the equipment and needs to be returned to the factory for repair. Among them, the switching circuit structure is as follows: four double-pole double-throw relay switches are used. After adopting the present invention, technicians can remotely know the working status of the equipment, and can realize remote correction when the measurement data deviates.

Description

technical field [0001] The invention relates to the field of grounding resistance monitoring, in particular to a grounding resistance monitoring instrument with self-checking and correction. Background technique [0002] Grounding resistance is the resistance encountered when the current flows from the grounding device into the ground and then flows to another grounding body or spreads far away through the ground. The grounding resistance value reflects the good degree of contact between the electrical device and the "ground" and reflects the scale of the grounding grid. The function of grounding is mainly to prevent people from being hit, equipment and lines from being damaged, preventing fire and lightning strikes. When a current flows into the soil from the grounding body, there will be resistance in the soil, which is the grounding resistance. Grounding resistance is the main technical parameter of the grounding system and an important indicator to measure the engineer...

AI Technical Summary

Problems solved by technology

During the long-term working process of the equipment, there may be problems such as device aging and inaccurate parameters. There are basically no grounding resistance monitors with self-test function on the market, and it is completely impossible to know the quality of the equipment and the accuracy of the data remotely.

However, it is impossible for technicians to be there in real time. They can only realize the self-inspection and calibration of the equipment by issuing commands to the equipment. However, there is no related technology on the market for this technology, and it is basically on-site maintenance.

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