An amperage breaker in a clothes dryer serves to protect the branch circuits inside the machine from electrical overloads. The breaker also trips itself in the event of a prolonged electrical short circuit or if the flow of electricity into the machine is at unsafe levels.
As of 2015, most clothes dryers are connected to a house amperage breaker that can accommodate up to 30 amps. Other appliances that are protected by an amperage or circuit breaker include lights and cooking ranges. A light bulb is protected by a 15 or 20 amp breaker, while a cooking range can be protected with a 40 amp breaker.