Editing Single-line diagram (section)

==Unbalanced systems==
When using the method of [[symmetrical components]], separate single-line diagrams are made for each of the positive, negative and zero-sequence systems. This simplifies the analysis of unbalanced conditions of a polyphase system. Items that have different impedances for the different [[phase sequence]]s are identified on the diagrams.  For example, in general a [[Electric generator|generator]] will have different positive and negative sequence impedance, and certain transformer winding connections block zero-sequence currents. The unbalanced system can be resolved into three single line diagrams for each sequence, and interconnected to show how the unbalanced components add in each part of the system.