pablo r. reyes
Member
Gentlemen,
In a distribution panel with system voltage of 480V-380Y/220V, feeding 3 identical branch circuit loads of 10kVa, distributedly connected to line to ground (220V - Ground). I would like to know, what is the basis for sizing the main OCPD for these loads? Is it 10,000VA/220V = 45.45A? Square root of 3 is not necessary. In my understanding, multiplying factor 1.732 will be used only when the loads are connected to line to line, that is 380V L-L. Here the line current is 1.732 x phase current. But for Line to Ground connection of loads, I think multiplying factor 1.732 is not necessary in order to obtain the line current, because the line current is equal to phase current. Please help me about this.
In a distribution panel with system voltage of 480V-380Y/220V, feeding 3 identical branch circuit loads of 10kVa, distributedly connected to line to ground (220V - Ground). I would like to know, what is the basis for sizing the main OCPD for these loads? Is it 10,000VA/220V = 45.45A? Square root of 3 is not necessary. In my understanding, multiplying factor 1.732 will be used only when the loads are connected to line to line, that is 380V L-L. Here the line current is 1.732 x phase current. But for Line to Ground connection of loads, I think multiplying factor 1.732 is not necessary in order to obtain the line current, because the line current is equal to phase current. Please help me about this.