Dividing consumers into groups according variant running character and variant load succession rate,calculating power of every group according different experiential value of demanding coefficient,sum of power of every groups multiply synchronization coefficient is total calculational power.

Taking one factory of six side top group control compound compressor for example, it tests & calculates the fixative method of its electricity coefficient, fixes needed electricity coefficient and proves the rationality of needed coefficient by operative practice.

This paper discusses mainly the residential current load and the analysis of the required coefficient, the power distribution system and questions concerning earth connection protection and safety in the designing of residential power distribution.