Abstract: In the space with complex equipment layout,the density of various electro-mechanical products and electronic devices continues to increase,and the coupling effect of various factors such as circuit,magnetic field and mechanical motion should be considered in product design,especially the matching of characteristics between devices should be confirmed.Taking the abnormal action of a lifting device as an example,the mechanism of common frequency interference when the proximity sensor and the stepper motor work together is explained,and the importance of device characteristic matching in the design of electro-mechanical products is expounded.

Key words: Lifting working device, Abnormal action, Proximity switch, Common frequency interference