what does the earth wire do in a plug
Relevance. Rating Newest Oldest. Best Answer: - the earth wire is connected to the metal casing of an appliance. - if a live wire becomes loose and touches the casing a momentary large surge of current is drawn from the live wire and goes through the earth wire to the earth so that nobody gets hurt by an electric shock.- the large surge in current also blows the fuse.he Neutral wire provides the return for the circuit but the Earth wire is the secondary return should a fault develop to protect the user and normally connected to ground via metal parts of the appliance. For a more detailed explanation google and good luck with your test.