In 2020, The National Electrical Code updated its requirements to include installation of arc fault devices on all new circuits and even on some existing ones. It states that pretty much all livable space in a homes is required to be protected.

To understand what an arc fault device is or why we might need them, first we need to understand what a regular breaker is and how it functions.

The standard breaker we have in most our homes built before 2015 is the same technology we have been using since the mid-1950s. Its safety components are comprised of a thermal plate and magnets. Its actually a bit archaic if you think about it.

The first line of defense is the thermal plate. When the circuit the breaker is serving begins to overload whether it be from a refrigerator motor going out, or from a few space heaters drawing too much energy, the plate works just like your HVAC thermostat. It senses the build up and opens the circuit shutting power off.

The second function is the magnets. When the breaker is turned on the magnets are pulled together. When a short occurs and there is a massive explosion of energy, it breaks the magnets apart causing the circuit to open and power to shut off.

SO NOW WE CAN MOVE ON TO OUR NEXT QUESTION.
WHAT IS A FAULT?

To be as concise as possible, a fault is simply a deviation in the proper flow of power. In a working circuit power flows back and forth from neutral to hot and back in a complete circle (circuit). A fault would be any other path the electrons might take instead of their intended course.

WHAT IS AN ARC?

As you have already imagined by hearing this word, an arc is the act of electricity jumping from one point to another through open air. The most common occurrence of this type is a small break in a wire, or a bad connection at the device. Just imagine two pieces of metal so close to each other they are almost touching.

Because this is still the least path of resistance, the electrons will physically jump from one end to the other, creating an arc. Believe it or not these are more common than we would like to believe, because they do not show themselves until something bad happens. A small arc over a long period of time can become super-heated, causing combustion of surrounding materials. In your wall this would be wood insulation or plastic.

So now that we know what an arc is, what a fault is, and how our old breakers work, we can begin to understand why we would be inclined to protect ourselves better with updated technology. Yes of course it all comes with a price point. The new breakers are literally 10 times more expensive than their traditional counterpart. But when it comes to our families safety and peace of mind it is well worth the investment.