Symmetrical three-phase circuit is shown in the figure, the known parameters are as follows, then the reading of the power meter 1 is W1=_____W, the reading of the power meter 2 reads W2=_______W. Choose A or B. For the power meter 1, it measures the line voltage UAB between A and B , the line current value IA through the fire line A, and the phase angule between the measured voltage and value. We have known that the phase degree of the line voltage UAB is equal to 0 degree, the phase angle of the line current IA is equal to negative 60 degree. So φ=ψu-ψi=60 degree, the power meter reading is P1=UABIAcosφ=380*1*cos60°=190W, and the reading of the power meter 2 is not the same as the power meter 1 . The phase angle of the line voltage of UCB is 60 degree. The phase angle of the line current of IC is 60 degree. φp=ψu-ψi= 0 degree P2=UCBICcos φ = 380W.