Clamp-on Grounding Resistance Measurement Device Based on MSP430

摘要

This paper presents a grounding resistance measurement device based on MSP430.The device makes use of variable-frequency measurement technology, which can automatically select frequency to avoid strong interference band. Therefore it has strong anti-interference ability. Digital filtering and Discrete Fourier Transforms (DFT) techniques are introduced to the system to eliminate the grounding noise and harmonic interferences effectively, which guarantees high measuring accuracy. The results of sim ulation measurement in laboratory show that the performance of the measurement is stable and the device has a strong anti-interference ability, furthermore, the accuracy of the device is quite high.