This paper mainly considered the Satellite components sensor location method considering time delay of the system information transmission under diagnostic criteria. A method of transferring the dynamic signed directed graph (SDG) to the static SDG was proposed. After that, technique on sensor location was researched using the static SDG. Means of defining the root nodes that represented the diagnostic character, including the detectability and the isolability, were put forward. Incidence matrix was introduced in order to up build the relationship between the root nodes and the senor points. Finally, greedy arithmetic was used to complete the sensor location satisfied the diagnostic criteria.