A balanced 3-φ, star connected load consist of three coils each consisting of R = 6 Ω and XL = 8 Ω. Determine the 1) Phase impedance 2) Phase voltage 3) Phase current 4) Line current 5) Power factor when connected across 400 V, 50 Hz supply.

Given: star connection, R = 6 Ω, X_L = 8 Ω, V_L = 400 V, 50 Hz.

1) Phase impedance: \( Z_{ph} = \sqrt{6^2+8^2} = \) 10 Ω (= 6 + j8 = 10∠53.13° Ω).

2) Phase voltage: \( V_{ph} = \dfrac{V_L}{\sqrt3} = \dfrac{400}{\sqrt3} = \) 230.94 V.

3) Phase current: \( I_{ph} = \dfrac{V_{ph}}{Z_{ph}} = \dfrac{230.94}{10} = \) 23.09 A.

4) Line current: in star I_L = I_ph = 23.09 A.

5) Power factor: \( \cos\phi = \dfrac{R}{Z} = \dfrac{6}{10} = \) 0.6 lagging.

(Additionally: P = √3 × 400 × 23.09 × 0.6 = 9600 W = 9.6 kW = 3 × 23.09² × 6 ✓; Q = 12.8 kVAR; S = 16 kVA.)