Arc fault vs ground fault

[new land owner]

Is it true that Arc fault breakers are required in Bedrooms but Ground fault breakers are still ok for kitchens and bathrooms, or are there other rooms in the house that require Arc fault?

[lobster]

what you said is true as far as i know, but in kitchens the exception is: no ground fault interrupter on the outlet for the fridge. this is because a GFI outlet is not as reliable as a simple outlet, and a false fault detection (caused by line surge or simple electronic failure) could lead to a big mess of decayed food etc. if not detected in time.

[flyingvan]

I was only required to use arc fault in the bedroom.  You wouldn't want it in the kitchen---not only because they are expensive, but electric motors are a constant arc while they are running (I can't plug my old drill in in the bedroom) and they often fool the circuitry in an arc fault.  Fridges, mixmasters, margarita blenders---all electric motors.  Common in kitchens, rare in bedrooms.  You are going to have to plug the rock tumbler in elsewhere.

[MushCreek]

I finally found it in NEC 2008, 210.12

210.12 Arc-Fault Circuit-Interrupter Protection.
(A) Definition: Arc-Fault Circuit Interrupter (AFCI). A
device intended to provide protection from the effects of
arc faults by recognizing characteristics unique to arcing
and by functioning to de-energize the circuit when an arc
fault is detected.
(B) Dwelling Units. All 120-volt, single phase, 15- and
20-ampere branch circuits supplying outlets installed in
dwelling unit family rooms, dining rooms, living rooms,
parlors, libraries, dens, bedrooms, sunrooms, recreation
rooms, closets, hallways, or similar rooms or areas shall be
protected by a listed arc-fault circuit interrupter,
combination-type, installed to provide protection of the
branch circuit.

To me, that sounds like everything other than the rooms on GFCI, such as bathrooms, kitchens, garage, and outdoors. I have an electrician friend who thought the arc-fault breakers might not be compatible with ground-fault outlets. To make things even more interesting, they now require tamper-proof outlets as well. Arc-fault is handled at the breaker; ground-fault usually at the outlet, although they do make ground-fault breakers. Brace yourself- all this stuff ain't cheap!

[Rob_O]

electric motors.  Common in kitchens, rare in bedrooms.

Lets not forget all those bedrooms with ceiling fans. Most of them (along with a lot of the devices you named) use induction motors that cause no problems but I had one customer that could run the fan only if he turned the light on

Brace yourself- all this stuff ain't cheap!

Halfway through a remodel we had to change out a bunch of breakers because the State adopted the new code, homeowner was unhappy to say the least

[MushCreek]

Ummm.... Does this mean that every time you plug in the vacuum cleaner (electric motor) you are going to have a problem???

[flyingvan]

  Possibly, especially if it's older.  My new drill does fine.  Ole' sparky trips the Arc fault.  Only my bedroom outlets were required by local code, not the ceiling

[MountainDon]

A Google for AFCI problems, found several references to people having various things from ceiling fans to vacuums tripping the AFCI. Sometimes replacing the fan, vacuum, etc with a newer or higher grade model resolved the issue. Sometimes it only reduced the frequency of false trips.  I also noted that since the AFCI rule came out, over the years it has been modified to include all devices in the bedroom. Various jurisdictions may or may not have implemented all the changes. Sounds like an imperfect technology to me.