总功率8KW、每相电热管额定电压380V时，电热管每相电阻：R=U*U/(P/3)=380*380/(8000/3)=54欧，角接电流：I=P/1.732/U=8/1.732/0.38=12A，星接电流：I==380/1.732/54=4A
