Experimental Study on Arc Motion and Electrode Erosion Behavior of MCCB

This paper presents a platform for electrode erosion diagnosis of a low-voltage molded-case circuit breaker based on in-situ optical diagnostics. The platform enables rapid in-situ measurements of the droplet splashing erosion behavior during electrode arcing. Using this platform, the splashing erosion behavior of the electrode under different arcing currents and with different polarities are studied. Additionally, the motion of the arc under different operating conditions is observed and analyzed. The findings of this work contribute to understanding the motion of the arc root and the splashing erosion characteristics of the electrode during the circuit breaker opening process, providing reference for predicting breaker interrupting performance and optimizing the design of the contact system.