a. Step and tough potential will increase more than maximum tolerable value.
b. Under single line to ground fault the voltage to earth of the two healthy phases rises from their normal phase to neutral voltage to full line voltage, which may result in insulation break down.
c. The capacitive current in two healthy phases increases ª3 times the normal value.
d. The capacitive current in the faulty phase is 3 times its normal value.
e. Experience shows that capacitive current in excess of 4 amps may be sufficient to maintain an arc in the ionized path of the fault and this persistent arc phenomenon is called ARCING GROUND, which ultimately cause high voltage build up.
Some time these voltage builds up to 5 to 6 times its normal value, which results in break down of insulation.
f. Being fault current low, it is difficult to isolate fault.