Abstract Moulded-case circuit-breakers needs greater structure strength to ensure its safety in the use and shipment. The finite element model for moulded-case circuit-breakers and ground is built in thisPaper. The stress and deformation of the moulded-case circuit-breakers are both investigated in the extreme condition when the moulded-case circuit-breakers atr vertically positioned to fall down. The results show that the stress and deformation is distributed asymmetrically. The maximum stress and deformation appear at the internalParts and the decorative plate due to impact stress wave, respectively, which also arise in the rebound process. The research provides scientific guidelines for designing the moulded-case circuit-breakers to avoid the falling.
2022, Vol. 23 
