继电器寿命终了时分断过程中的熔焊现象

Welding Phenomenon of a Relay in the End of Lifetime During Breaking Period

触点熔焊是继电器最为严重的故障形式之一。笔者对两种实验样品商用继电器和触点模拟试验装置进行了大量电接触实验,分析了触点熔焊前分断燃弧时间的变化规律,指出熔焊的发生具有随机性和突发性,熔焊发生前分断燃弧时间比较稳定,单纯从分断燃弧时间上很难预测熔焊的发生时刻。最后得出熔焊既可以发生在触头闭合过程,也可能发生触头分断过程。

Welding is one of the worst faults for an electromagnetic relay. In order to find out the variation rule of arc duration in breaking period before welding, a large number of electrical contact experiments on both commercial relay and simulation test device under different voltages were conducted. The results show that welding may occurs randomly or suddenly, and predicting welding moment only according to arc duration in breaking period is difficult. Welding can take place in a relay either during closing period, or during breaking period.