So since this thread started it, here you go...
An arc-fault circuit interrupter (AFCI) also known as an arc-fault detection device (AFDD)[1] is a circuit breaker that breaks the circuit when it detects an electric arc in the circuit it protects to prevent electrical fires.
An AFCI selectively supposedly distinguishes between a harmless arc (incidental to normal operation of switches, plugs, and brushed motors), and a potentially dangerous arc (that can occur, for example, in a lamp cord which has a broken conductor).
AFCI breakers have been required for circuits feeding electrical outlets in residential bedrooms by the electrical codes of Canada and the United States since the beginning of the 21st century; the U.S. National Electrical Code has required them to protect most residential outlets since 2014,[2] and the Canadian Electrical Code has since 2015.[3]
In parts of the world using 230 V, where the higher voltage implies lower currents, specifically Western Europe and the UK, adoption is slower, and their use is optional, except in high risk cases.
In the US, arc faults are one of the leading causes for residential electrical fires.[4] Each year in the United States, over 40,000 fires are attributed to home electrical wiring.
These fires result in over 350 deaths and over 1,400 injuries each year.[5]
Ok so ends the supposed reasons for ACFI breakers...
Now how do they work?
Conventional circuit breakers only respond to overloads and short circuits, so they do not protect against arcing conditions that produce erratic, and often reduced current.
AFCIs are devices designed to protect against fires caused by arcing faults in the home electrical wiring.
The AFCI circuitry continuously monitors the current and supposedly discriminates between normal and unwanted arcing conditions.
Once detected, the AFCI opens its internal contacts, thus de-energizing the circuit and reducing the potential for a fire to occur.
Great! So then what is the problem?
Well the problem my friends - for all the non-electrical engineers out there is inductance! The property or a wire to resist the change of the flow of current and to generate a magnetic field and store and release energy because of flow...
Humm - well the problem is that a great many things produce stray voltage in wiring - like the flow of current in an adjacent wire or magnetic fields, or lightning or even sun spots!
And many of these stray currents (perhaps all to those of us who hate these things!) looks like an arc to these dumb breakers and they trip!
So the bottom line is that a device designed to help prevent fires and help us is helping us rip out our hair in frustration!
So because the holidays are near I wish you a very Merry Arc fault and a happy new year!