UTILITY CONTRIBUTION 1

[SRA007]

Dear Friends,
What type of fault(ik,ib,ip) do we use for utility contribution while running a electrical study.

 

[deltawhy]

What type of study? If you are doing a fault, coordination or arc flash study you will need the positive and zero sequence Thevenin equivalent impedance at the system connection point (which translates into the LLL and LG amps with the X/R ratios).

 

[dpc]

What type of fault(ik,ib,ip)

FWIW, that terminology means nothing to me here in the USA - and I've done a lot of fault calculations.

 

[7anoter4]

ik [I"k,Ik], ib and ip are not "types" of a fault but different current values in the case of the same fault [definitions of IEC 60909-0] :
Initial symmetrical short-circuit current I"k
peak short-circuit current ip
symmetrical short-circuit breaking current Ib
steady-state short-circuit current Ik
Usually an utility may transmit initial symmetrical short-circuit power S"k
and may be the System impedance at your connection point [or reactance to resistance ratio].
However "types" of short-circuit current could be:
line-to-line short circuit, line-to-earth short circuit, line-to-line short circuit with earth connection.