1 phase opened fault in PSS/E

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Yes, you can do that for branches without susceptance, i.e. B=0. First you have to take the branch out of service. Use SCMU - 2 phases closed - and enter the impedance of the branch, see picture below and POM 10.4.2.

Here I have first taken the existing branch between bus 3001 and 3003 in savnw.sav out of service.