Murray loop test is performed on a faulty cable 300 m long. At balance, the resistance connected to the faulty core was set at 15 Ω and the resistance of the resistor connected to the sound core was 45 Ω. Calculate the distance of the fault point from the test end.

• A. 75 m
• B. 450 m
• C. 225 m
• D. 150 m

Answer: (D)

Where,
R2 is the resistance connected to the faulty core in ohm
R2 is the resistance of the resistor connected to the sound core in ohm

R1 Distance of fault location (Lx) = R2/(R1 + R2)*(2*L)
= (15/60)*600
= 150 m