Power factor

[PE blues]

I thought I had this figured out, but the Chalapti book seems to be doing it differently.

A building is supplied by a 480 V four wire service. The building has a 3 phase motor load of 185 kW at 0.8pf. What is line current?

I=185(ang-36.86)/(1.73*480(ang30)*0.8)

Why are they including the 30deg for voltage? When power factor is given, isn't it with respect to voltage so we can neglect the 30 voltage angle?

 

[BamaBino]

If the supply is Wye and the motor is Delta, there would be a 30 degree phase difference between line current and line voltage.

 

[Wildsoldier PE]

If the supply is Wye and the motor is Delta, there would be a 30 degree phase difference between line current and line voltage.

Eng. BamaBino long time no see!! I guess you took a looong vacation after passing your PE...hehe

 

[cfanone]

Is it because the V Line of a wye leads the Vn by 30?

 

[PE blues]

So if both the load and supply are star, the power factor given is w.r.t load voltage => w.r.t line voltage, and to calculate line current, angle can be neglected?