小型断路器热脱扣稳定性的分析计算

摘要

While in MCB structure design or different standard applied on same MCB, such as IEC 60947 or IEC 60898, for bi-metal,it needs checking and calculation for thermal deflection and thermal push force, which is on different condition with standard tripping current,in order to match the bi-metal tripping characteristic with MCB mechanism.This article has a detailed description for impact elements and proposed how to improve the MCB thermal tripping stability.%小型断路器(MCB)在结构设计时,同规格MCB适用不同产品标准时,如IEC60947和IEC60898,需要对约定电流范围内的热弯曲位移和热推力进行校核计算,以匹配脱扣机构的脱扣位移和脱扣力.结合产品实例,计算了直条型双金属的热弯曲和热推力,推算和总结MCB具备热脱扣稳定性的必备条件,给出了提高MCB一次交验合格率的建议.