The technical requirements for secondary equipments of the new generation intelligent substation is illustrated in detail, and some integration schemes are proposed for secondary equipments used in common connection forms of main electrical wiring, such as monitoring system equipments, energy metering equipments, fault recorder equipments and phase measurement unit (PMU). Then, the function of monitoring system is studied. The integration of relay protection devices is also discussed in accordance with the relay protection configuration under double-busbar and 3/2 connection form. It presents a recommended integration way based on the comparison of integration schemes of secondary equipments, such as monitoring system, relay protection and so on. Finally, the technical issues that should be focused on equipments intelligent is proposed, with considering the constraints that might affect device integration such as the occupied bandwidth of sample measured value (SMV) message (based on calculation), fiber ports density of secondary device backplane and cubicle space, etc.