why is a fuse always plased in a live wire?

Hi,

 

A fuse in a circuit prevents damage to the appliances and the circuit due to overloading. Overloading can occur when live wire comes in contact with neutral wire. At this time current abruptly increase and due to joule heating fuse melts and break the circuit.

That’s why fuse always connected in live wire.

 

Hope, this helps you.

Best wishes!!