The relays aren't what is causing these wires to melt.

A poor connection is what is causing it.

When you have a poor connection it creates resistance, resistance creates heat, heat causes the connection to become worse creating more resistance and more heat until you have a failure.

Quote Originally Posted by sniffle View Post
... Got a 30A auto relay... All I could find... It melted wires today... Gonna get a 40A to hopefully fix it