The electrical equipment in substation may be severely damaged in the seismic condition. Most of previous studies have focused on the seismic performance of single devices or single-span coupled systems

but in practice

multiple devices coupled through flexible wires will affect the seismic response of other equipment. Therefore

a kind of numerical solution based on motion equation is proposed for the seismic response of multi-span flexible wire-single device coupling system. For the accuracy of the method

a corresponding finite element model of the five-span coupling system containing six different electrical equipment is constructed

and the seismic response analysis results of both are compared. Then

the effects of equipment frequency and the vertical span ratio of the flexible wire on the seismic response of the coupling system are studied. The analysis shows that the numerical method is in highly agreement with the calculation result of the finite element model

and the absolute values of the maximum relative errors of peak acceleration and relative displacement are 9.85% and 10.64%

respectively

and the wire tension and seismic response of equipment as well as the frequency ratio of adjacent equipment are positively correlated. This method has practical significance for improving the seismic design and configuration of electrical equipment at substation.