Circuit breakers are rated for a certain maximum current and will trip if that current is exceeded. This is to prevent electrical discharge and a possible fire from short circuits or faulty wiring. Because breakers are re-useable, the modern electrical panel is an improvement over the fuse boxes in older homes.

Protection from Circuit Overload

Not all tripped breakers signify a dangerous situation. In fact, the most common cause of tripping is circuit overload, which can often be corrected by unplugging an appliance or turning off a light. Using an appliance rated for an amperage greater than the breaker is designed for will also trip it.

Dangerous Short Circuits

A tripped breaker may also be the sign of a dangerous short circuit. This can happen because of a defective appliance or it can be a fault in the wiring. Short circuits allow electricity to pass unhindered through the circuit, overheating the wires and potentially starting fires.

How a Breaker Works

Breakers employ small electro-magnets that are powered by the current running through them. The strength of the magnetism varies with the current. When the current is too high, the magnet attracts a lever which opens the circuit, shutting off the electricity.

Defective Breakers

Breakers can be defective and create a hazard. This can happen if the humidity is high or water has gotten into the panel. If a breaker is tripped and will not reset even with all loads removed from the circuit, it is advisable to check it with a voltmeter or replace it.

Ground Fault Interruptors

GFI receptacles employ a type of breaker that detects the sudden diversion of electricity to ground, as when someone inadvertently touches the hot wire. GFI's trip easily in wet weather and should be inspected in the event of an outage. A tripped GFI will cut power to all elements in the circuit after it.

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Continually tripping breaker