Question

Why excess current flows through the circuit sometime?

Answer 1

due to low resistance

Answer 2

excess current can flow thru the circuit because of shortcircuiting which is a result of overloading.

Overloading can be caused when:

1. a live wire and a neutral wire come in contact.

2. when there is a fault in the insulation of wires or with the device itself

3. when too many devices are connected to one circuit.

4. there is an accidental hike in the supply of voltage.