Surge load experiment design and results analysis of relay

Due to the transient overvoltage or overcurrent when relay´s contacts switch different loads, the relay´s contacts are damaged by transient arc erosion of electrical-over-stress, which influences the reliability of relay seriously. Firstly, according to the life test requirements of one type of electromagnetic relay with permanent magnets, the load circuit and the testing program are designed, which has characteristic of adjustable surge current time. Secondly, the contacts´ breaking arc and closing bounce under 2A resistive load, 5A resistive load and surge load are analyzed. The influence of surge load on relay´s electrical life is studied with increasing of test cycles. Finally, based on the testing data, the optimal design of relay has been modified and the results have been analyzed, which is helpful for improving the life of the relay.