For the positive , negative as well as zero sequences of sequence networks are developed independently by combining the sequence circuits of all the individual elements . Certain assumptions are listed below while causing the sequence networks .

In addition to synchronous machines , the network is made of static elements .

The voltage drop because of the current in a particular sequence depends only on the impedance of that part of the network .

The positive and negative sequence impedances are equal for all static circuit components , whereas the zero sequence component will not need to be the same as them . Furthermore subtransient positive and negative sequence impedances of a synchronous machine are equal .