The prospective fault current for an installation is to be measured at the origin of a polyphase installation, the highest measured value is likely to be between
A) L1 - E
B) L1 - N
C) L3 - N
D) L1 - L2

Question

Quizplus · Accepted Answer

The prospective fault current is the maximum current that could flow in the event of a fault. In a polyphase installation, the highest value is likely to be between the phases (L1-L2) rather than between a single phase and earth or neutral. Therefore, option D (L1-L2) is the best choice.

The Prospective Fault Current for an Installation Is to Be