Thread: Buzzing AFCI

I have noticed that some of the blue Square D AFCI breakers make a buzzing noise. I know there has been a recall on these breakers, and want to know if the buzzing noise is deficient?

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Here's a previous post about it:
AFCI - Home Inspection & Home Inspector Services For Inspections and Inspectors

Here's another:
Humming Arc Fault Breakers - Home Inspection & Home Inspector Services For Inspections and Inspectors

Thanks for the info.

Harmonics on the AC line due to uncorrected capacitive or inductive loads will cause a shift in the waveform of the line current that could result in a " nervous" AFCI breaker.

The combination AFCI breakers themselves are always working electricity, as long as the mains are energized and passing electricity to the buss(es) and the AFCI breakers themselves aren't fully cycled (completely) off.

Power supplies (integral or not), caps and/or ballasts and equipment, devices or appliances containing same, low or line voltage dimmers, fan/motor controls, switch devices with indicating lights, "solid state" equipment, etc. can noticably increase the "hum" or "buzz" you detect at the combination AFCI circuit breaker.

Current Q&A from Siemens regarding both QO and HOM AFCI breakers product information (clickable direct links from siemens square D products web site(s) are provided citation above each quotatiion below) regarding the "warmth" you detect compared to other breakers in the same panel, and "the hum" you may feel or hear coming from same:

from (last updated Dec 2011) AFCI - Arc Fault Circuit Interrupters Frequently Asked Questions?

Could an AFCI feel warmer than other breakers in the same panel?

An AFCI breaker may feel warmer to the touch than a non-AFCI circuit breaker. This is due to the heat generated from the power supply for the electronics. Siemens AFCI breakers tested in an average ambient temperature of 23 degrees C (73 degrees F) operated at an average temperature of 38 degrees C (100 degrees F). This is well within the UL Standard 489 Section 7.1.4.1.6 which states - Temperature rises on handles, knobs, and other surfaces subject to user contact during normal operation shall not exceed 60 degrees C (140 degrees F) on nonmetallic surfaces. It is warm enough to detect with the hand, but this heat does not impact the operation of the AFCI.

from (last updated Jan 14, 2011) (clickable link): My QO arc fault breakers are humming. Are they OK? | FAQs | Schneider Electric US

My QO arc fault breakers are humming. Are they OK?

The electronics inside the breaker will produce a low humming noise. Solid state dimmers will make them buzz louder, but this is normal and is no cause for concern.

from (last updated Jan 14, 2011) (clickable link): My Homeline arc fault breakers are humming. Are they OK? | FAQs | Schneider Electric US

My Homeline arc fault breakers are humming. Are they OK?

The electronics inside the breaker will produce a low humming noise. This is normal and is no cause for concern.

Regarding recalls, you can find infomation on both Siemens' and the CPSC web sites, which includes the means to identify same. You can also find information on CPSC and UL web sites with regards to counterfeit "Square D" look-alike breakers and combination breakers, including both GFCI and AFCI combination breakers.

HTH.

I have poor hearing. That sets a standard for me and breakers. If I can hear a hum, I will advise the client.

Originally Posted by Darrel Hood

I have poor hearing. That sets a standard for me and breakers. If I can hear a hum, I will advise the client.

Will you tell them that this is normal or a defect?

Using the required Texas reporting format anything that is not perfect is deficient, no choices. Also, if I can hear it without putting my head inside the box, something is wrong with the device.

But you were just shown that this is a normal charecteristic of an AFCI breaker, and you would still report it a a defect?

I also said I don't hear well. If I can hear it, it is defective.

I would certainly be miffed if someone unnecessarily called out something that was a normal condition . Especially if I hired someone to check out this so-called defect.

Originally Posted by Jim Port

I would certainly be miffed if someone unnecessarily called out something that was a normal condition . Especially if I hired someone to check out this so-called defect.

From what I have seen of Texas reports, not many I admit, a note is added that the deficiency was reported as such because the law says they have to report it as such.

One of the benefits of home inspections and reports set by a Real Estate Association.

I fail to understand how something that is operating normally needs to be called out as a defect.

Must be the same logic the insurance companies use to determine that a small house with all gas appliances still requires a 150 or 200 amp service otherwise they won't insure it.

Originally Posted by Jim Port

I fail to understand how something that is operating normally needs to be called out as a defect.

Must be the same logic the insurance companies use to determine that a small house with all gas appliances still requires a 150 or 200 amp service otherwise they won't insure it.

Is it no differnet than HI's applying the most recent code to things built years ago to different standards, and implying that they are some how defective (or not code compliant) because they don't meet the most current standard?

Corey

Jim,
In the case of my statements, we are discussing not if it is buzzing, but how loud it is buzzing. I use a hearing aid in many circumstances. I use head phones to hear a television. When I am in the room with normal hearing people and a properly adjusted television volume, I hear no sound from the television. I require a special telephone. So yes, if I hear the device buzzing with my unaided hearing, something is not normal.

Originally Posted by Darrel Hood

Jim,
In the case of my statements, we are discussing not if it is buzzing, but how loud it is buzzing. I use a hearing aid in many circumstances. I use head phones to hear a television. When I am in the room with normal hearing people and a properly adjusted television volume, I hear no sound from the television. I require a special telephone. So yes, if I hear the device buzzing with my unaided hearing, something is not normal.

I disagree. My profoundly deaf (since birth) grandson can feel (detect) the intensity of a normal buzz or hum of energized combination AFCI circuit breakers even when not making physical contact with any portion of the electrical system or the cabinet, or dead front, furthermore it is enhanced when removing the deadfront securing screws.

Basement panel mounted off wall on board - he can still "feel" it.

Readily enhanced using a non-(electrically) conductive "sounding (feeling) tool" such as a dowel stick.

'sounding' mechanical and lower frequency (as opposed to a higher frequency ferad type whine type hum or buzz) "hum"s or "buzzes" just like engine noises, etc. quite possible for the hearing impaired and the profoundly deaf. Point being if you're detecting it, its still not necessarily anything defective or out of line - and you should still be able to "feel" (detect) it ("normal" levels) despite even a major impairment to your "hearing" system, before you remove the deadfront and contact the front of the AFCI CB.

From one of Watson's posts above:

(bold and underlining is mine)

- from (last updated Jan 14, 2011) (clickable link): My QO arc fault breakers are humming. Are they OK? | FAQs | Schneider Electric US
- - My QO arc fault breakers are humming. Are they OK?
- - - The electronics inside the breaker will produce a low humming noise. Solid state dimmers will make them buzz louder, but this is normal and is no cause for concern.

- from (last updated Jan 14, 2011) (clickable link): My Homeline arc fault breakers are humming. Are they OK? | FAQs | Schneider Electric US
- - My Homeline arc fault breakers are humming. Are they OK?
- - - The electronics inside the breaker will produce a low humming noise. This is normal and is no cause for concern.

Keep in mind that is for the public to read and 'feel good' about the AFCIs making noise, as such there is no definition of how loud "low" is. Realizing that "low" is vague, and that the intent is to reduce complaints, "low" may actually mean 'quite noticeable'.

Without some meaningful decibel level of reference, unless the AFCI shaking away and rattling the cover screws ... is the AFCI actually 'bad'? I believe that is what several people are trying to point out to Darrel.

Jerry,
I understand what the folks are saying. However, I will not accept that a properly operating AFCI will make loud noises. You reinforced my thinking with the emphasis on the word low in your posts. Since there is no standard definition for the term, my definition is as good as any. So is yours for your clients. Thanks folks.

Originally Posted by Jerry Peck

- - - The electronics inside the breaker will produce a low humming noise. This is normal and is no cause for concern.

Originally Posted by Darrel Hood

Jerry,
I understand what the folks are saying. However, I will not accept that a properly operating AFCI will make loud noises. You reinforced my thinking with the emphasis on the word low in your posts. Since there is no standard definition for the term, my definition is as good as any. So is yours for your clients. Thanks folks.

Keep in mind that does not say that 'not low' is 'abnormal'.

Now, I suppose that 'smoke alarm loud' would most likely be considered 'abnormal'.

Personally, I think Arc Fault devices are presently the electric version of snake oil.

These devices shouldn't make enough noise to prevent someone from using a room the panel is in as a bedroom when needed - and some make enough noise that sleeping is out of the question. That swapping them out can sometimes get the racket stopped is proof they don't all behave the same. And they should

<RANT>
I've also observed that there are circuits that test just fine that trip AFCIs for no apparent reason when they are used for certain things, and the 5th or 6th replacement finally cured the problem. I suspect that there is an ongoing issue with the manufacturers diddling with the algorithm used for detecting an arc and they have multiple versions out with no way to tell them apart. Particularly annoying is finding that a device that tripped consistently on a circuit and was replaced by one that didn't, and now that device is in use on another circuit because the original on it had tripping problems. It seems to me that there should have been a data port built into these things so that the latest and greatest can be installed and that things like the GFCI portion can be disabled when needed (like on a multi-wire circuit) <RANT OVER> (for now)

Just today I heard a cell phone buzz from two rooms away, but the person sitting next to it did not. Maybe the phone is defective.

At the last two physicals the doctor has said I am losing my hearing.

[quote=Bill Kriegh;186665]Personally, I think Arc Fault devices are presently the electric version of snake oil.


yep -- And GFCI's were the snake oil of the 70's

Originally Posted by Jim Port

Just today I heard a cell phone buzz from two rooms away, but the person sitting next to it did not. Maybe the phone is defective.

At the last two physicals the doctor has said I am losing my hearing.

Jim ?? Jim ?? I swear I heard Jim, Did anyone else hear something?

I just came back from ASHI's IW and this was covered in one of the classes - the recommendation: report on any noise from an electric panel and I support this. What would concern me is whether the noise is indicative of any arcing that is occurring and that's where I'll shift the issue to someone else's plate.

[quote=ken horak;186906]

Originally Posted by Bill Kriegh

Personally, I think Arc Fault devices are presently the electric version of snake oil.


yep -- And GFCI's were the snake oil of the 70's

I've always been on board with GFCIs because I can test the conditions that cause them to trip and verify a circuit or utilization device is bad.

With AFCIs all I have been able to do is prove some of them trip when they shouldn't.

Originally Posted by Bill Kriegh

With AFCIs all I have been able to do is prove some of them trip when they shouldn't.

Maybe that's because the AFCI 'should' be tripping?

Originally Posted by Jerry Peck

Maybe that's because the AFCI 'should' be tripping?

Read all the posts Jerry. My experience is that a properly tested circuit tripped certain AFCIs and not others. No consistency. Sometimes one brand will trip and others won't, sometimes I can go through several of the same brand before finding one that doesn't trip. And, one of the AFCIs rejected for one circuit (but not all of them, necessarily) will work on another circuit sometimes.

Originally Posted by Bill Kriegh

Read all the posts Jerry.

I have read them, but your stand-alone sentence was just setting there waiting for a reply to it.

My experience is that a properly tested circuit tripped certain AFCIs and not others. No consistency. Sometimes one brand will trip and others won't, sometimes I can go through several of the same brand before finding one that doesn't trip. And, one of the AFCIs rejected for one circuit (but not all of them, necessarily) will work on another circuit sometimes.

And the above *does not mean any of the AFCIs are defective*, it 'may' simply mean that each manufacturer has their own arc signature they are looking for ... actually, they do have their own arc signature they looking for, and there is no standard at this time.

Some AFCIs from the same manufacturer may not trip while others may, and that could be from the +/- range built into every type of device. One simply cannot make things *exactly* *alike* all the time, there is always a range built into everything.

Similar to GFCIs when they first came out - they tripped on so many circuits that it became standard practice for many electricians all over the country to install GFCIs for the inspection, then go back and replace the GFCIs with non-GFCI receptacles - the electricians called it 'nuisance tripping for no reason', and, to a point, that may have been correct, however, I also suspect it may have partially been the sloppy installation practices electricians had been getting away with for years. New devices require greater care in the installation of the electrical system.

If any single AFCI installed anywhere in this country and it saves just one life ... all AFCIs are justified - correct? If not correct, what is the value you place on that life and how many AFCIs is it worth?

Jerry,
I learn a lot from you and you have earned my respect. However, sometimes you are stubborn and this is one of those times. There is no doubt to an observant person that AFCI technology is in its infancy and as such is having growing pains. The devices are not highly reliable for non emergency operation and are of unknown reliability for their intended function. However, they are probably doing no harm. Your argument about a life saved versus inconvenience is powerful, but leave it there.

Originally Posted by Darrel Hood

There is no doubt to an observant person that AFCI technology is in its infancy and as such is having growing pains. The devices are not highly reliable for non emergency operation and are of unknown reliability for their intended function.

Darrel,

No one has said, that I can recall, that AFCI are not in their infancy and are going through growing pains, in fact, as I recall, Bill made reference to "I've always been on board with GFCIs" and I pointed out that even GFCIs went through infancy and growing pains.

That did not make the GFCIs bad, thus it should not make the AFCIs bad.

When an AFCI trips, before jumping on the 'bad AFCI' bandwagon one needs to check *everything* in the circuit because the AFCI 'may not be bad' ... but I already said that in a previous post.

There are some who steadfastly refuse to acknowledge that AFCI 'may not actually be bad' ... just like there were those 'back then' who steadfastly refused to acknowledge that GFCI 'may not actually have been bad'. Guess one needs to have been around back when GFCI first came out to understand the fuss over 'what might be nothing' with AFCIs.

I recall an excellent updated article in IAEI Mag online last Sep/Oct 2011, "Required Technology to Prevent Electrical Fire Ignitions". Here is a clickable link to same: Required Technology to Prevent Electrical Fire Ignitions | IAEI Magazine

I think it is important to remember that not all AFCI devices are equal, there are different types. If you're comparing a branch/feeder type with a combination type you are comparing apples and oranges.

I sure hope B.K. and others who make such remarks will give it a read, It covers more than just AFCI devices please take a look.

In the meantime, here's highlights re:AFCI.

"In recent years, arc-fault circuit interrupter (AFCI) circuit breakers have been introduced to the market to prevent fires from arcing between wires. The first AFCI breakers were called “branch/feeder” type (USA) or “breaker” type (Canada). Branch circuit/feeder AFCI devices detect series arcing events at 80-85 amperes. Combination AFCI devices detect series arching events at 5 amperes. Because of this fact, branch circuit/feeder AFCIs did a much better job of detecting parallel arcing events than they did detecting a series arching event. UL 1699 Standard for AFCIs assumed that most fires from parallel arcing resulted from cracked insulation, line surges and resultant arc tracking. These interrupters were an improvement compared to overcurrent circuit breakers, but could not detect many arcing conditions that lead to fires."

"New AFCIs, “combination,” introduced late in 2007, now detect both series arcing (unintentional parting arcs) and parallel arcing. AFCI series arc detectors are designed to trip on arcs in-line with the circuit path (i.e., a loose wire connection) if greater than 5 amperes. Series arcing is a serious issue with fires directly associated with aluminum wiring where the energy associated with the arcing can be adequate to melt the aluminum and throw sparks (see NFPA 921, section 8.9.5). Series arcing can also pit and oxidize brass and steel contact points and lead to a high-resistance connection (see NFPA 921, section 8.9.2.3) of wires or contacts. High current flowing through a high-impedance connection is a leading cause of electrical fires."

"UL 1699 tests for AFCIs include both series and parallel arcing conditions. Series tests force parting arcs at 5 amps and above across a copper to carbon interface. Parallel tests create a parallel carbon conduction path of arc tracking by exposing damaged wires to 7.5 kV. These tests create a fairly consistent method for testing AFCI breakers, but do not necessarily represent realistic conditions. For example, series arcing from a copper rod to a carbon rod, as required by UL 1699, creates a sustainable arcing condition. Most residential branch circuits use copper wire only. Connections are copper to copper or copper to brass/steel. Series arcing from copper to copper (e.g., two wires under a wire nut) or from copper to zinc-coated steel (a wire screwed to a receptacle) self extinguishes quickly and is more difficult to detect consistently."

"Note, if an AFCI trips on a parallel arc fault, wire insulation damage has likely occurred. A crack in the insulation along with a carbonized arc tracking path between line and ground may exist. The UL 1699 test simulates these conditions using a slit in the wire insulation between the conductors plus application of high voltage to create an arc track path to ground. In the author’s opinion, if the AFCI device trips on a parallel arc, the AFCI device should not be resettable in this situation, since a pending fire ignition situation still exists. In contrast, if an AFCI trips on a series arc fault, the cause may have been a temporary contact-parting condition. In either case, an electrician should service the facility anytime an AFCI protective device trips to repair the fault condition."

HTH.