Answer / parvez alam

In 440 volts, 3-phase star connected system Vph=Vl/1.732 which is equals to 440/1.732=250V. So Vph is voltage between phase and neutral and Vl is line voltage between two phases. Also power in 3 phase system is 1.732VlIl x power factor.Also Il=Iph

But in delta connected system it is just the opposite of 3 phase system, so we have Vph=Vl because there is no neutral in delta system.Also Iph = Il/1.732 

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