CasterSkux
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Hello again,
I've got another question that involves symmetrical components, this time I've attempted it.
The Question follows:
1. In a 3 phase circuit with resistance earthed and neutral and Earth fault in phase “A” which produces a fault current of 800 amps.
Load currents may be taken as zero.
What will be the positive, negative and zero sequence currents in this system?
Answer
I have Ia = 800 for Phase A, Ib = 0 and Ic = 0 and I assume this is a Phase-to-earth fault
According to this source https://www.selinc.com/WorkArea/DownloadAsset.aspx?id=100688, when Phase B and Phase C is zero (as suggested by "Load currents may be taken as zero"): the zero,
positive and negative sequence are all 1/3Ia. It also says that when an phase to Earth fault happens in Phase A: Phase B and Phase C can be assumed to have no current anyway.
Therefore Ia = 800A and I0, I1, I2 = 267A. Is my answer and thought process right?
Cheers:)
I've got another question that involves symmetrical components, this time I've attempted it.
The Question follows:
1. In a 3 phase circuit with resistance earthed and neutral and Earth fault in phase “A” which produces a fault current of 800 amps.
Load currents may be taken as zero.
What will be the positive, negative and zero sequence currents in this system?
Answer
I have Ia = 800 for Phase A, Ib = 0 and Ic = 0 and I assume this is a Phase-to-earth fault
According to this source https://www.selinc.com/WorkArea/DownloadAsset.aspx?id=100688, when Phase B and Phase C is zero (as suggested by "Load currents may be taken as zero"): the zero,
positive and negative sequence are all 1/3Ia. It also says that when an phase to Earth fault happens in Phase A: Phase B and Phase C can be assumed to have no current anyway.
Therefore Ia = 800A and I0, I1, I2 = 267A. Is my answer and thought process right?
Cheers:)