GREETINGS, AS THE "elektomaq" COLLEGE SAYS EVERYTHING IS SIMPLIFIED THAT THE FUNCTION OF THE BREAKER IS TO PROTECT THE WIRING OF A SHORT CIRCUIT AND IN ITS DEFECT UNTIL A DOMESTIC FIRE, IF YOU USE A CABLE # 12 COMES FOR 20A AND 14 IT IS FOR 15A, AS THE COLLEGE SAYS YOU MUST MAKE CHANGE OF THE BREAKER SO THAT YOU KEEP PROTECTING YOUR WIRING INVESTMENT AND THE SECURITY OF YOUR HOUSE ... GREETINGS AND LOTS OF LUCK ... Either way HERE I LEAVE YOU THIS LINK AND I HOPE HELP YOU BETTER ...