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  1. #1
    Neil Hunter's Avatar
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    Default Universal Motors on AFCI circuits

    I have a recently completed bedroom addition protected by a single AFCI in a separate subpanel. I cannot plug in anything with a universal motor (vaccuum cleaner, hair dryer etc.) since the arcing at the motor brushes immediately trips the AFCI breaker. Any other appliances work just fine. While this behavior makes sense, it seems the requirement severely restricts the use of certain appliances or is my breaker just over sensitive?

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  2. #2
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    Default Re: Universal Motors on AFCI circuits

    you arent the first to experience this issue.
    you won't be the last person who needed to purchase new vaccum cleaners either


  3. #3
    A.D. Miller's Avatar
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    Default Re: Universal Motors on AFCI circuits

    A faulty neutral-to-ground connection on the load side of the device?


  4. #4
    Neil Hunter's Avatar
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    Default Re: Universal Motors on AFCI circuits

    I've still to check electrically but physically all looks good. Thanks for the suggestion.


  5. #5
    Roger Frazee's Avatar
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    Default Re: Universal Motors on AFCI circuits

    Did your local code require afci? Many local areas still are not adopting the new afci requirements of the NEC. This is an all to often issue with afci protected circuits and a huge headache for the contractors and homeowners. If you had said that anything plugged into that afci tripped I would say you have a wiring error or some fault issue. But if resistive loads like curling irons, lights, heaters etc don't trip it then likely the afci is faulty for whatever reason. There is no way you should have to go out and buy new vacuums, hair dryers etc. I'd see if a neighbor had a vacuum you could try and a hair dryer if it still trips.

    Is the afci cutler hammer ? These have been having huge problems with nuisance tripping with motor loads and you might as well trash it. Maybe return and try a new one.

    An opinion from another thread on a different forum on this subject ... I agree with it 100%

    "The problem is actually with the afci breakers.
    Are the vacuums and power tools causing or creating series or parallel arc faults? …Nope
    Are they causing 30 mA ground faults? …Nope
    AFCI’s are untested, unproven, unreliable and unnecessary technology that has been forced onto the electrical trade and its customers by the manufacturer lobbyists. The original non combo AFCI’s were a PITA and the new Combo AFCI’s are no better .. maybe worse. They are as close to 100% BS as you will find anywhere. They are in no way the same in importance as the development of the GFCI.

    If the NFPA really wants to save lives, they should find a way to limit the effect of portable electric space heaters in old buildings with already antiquated wiring systems, such as by lowering the wattage ratings that these can be manufactured at.
    The annual onslaught of fires from the use of these because of overloaded electrical wiring and contact with combustibles will begin next month, when the weather starts getting colder and fuel prices continue to rise. Should be a banner year! "

    I wouldn't lose any sleep jerking it out and installing a typical breaker.


  6. #6
    Neil Hunter's Avatar
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    Default Re: Universal Motors on AFCI circuits

    Roger: Code here requires them for bedrooms. I totally agree with your comments. I think it is a ridiculous requirement especially in new construction using all copper wiring and correctly installed. I need to check the mfgr of the breaker when I get home - can't remember if it's a cutler-hammer or whatever.I'm the owner-builder so chances are I'll just bypass the thing after final inspection - the circuit is already protected by a regular panel breaker before the AFCI. The 'bedroom' isn't even being used as a bedroom - it's really an upstairs bonus room (no closets) but because it has a 1/2 bathroom inside it, the city plan checkers in their wisdom said it has to be classed as a bedroom!

    Last edited by Neil Hunter; 01-15-2010 at 01:49 PM.

  7. #7
    Roger Frazee's Avatar
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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Neil Hunter View Post
    Roger: Code here requires them for bedrooms. I totally agree with your comments. I think it is a ridiculous requirement especially in new construction using all copper wiring and correctly installed. I need to check the mfgr of the breaker when I get home - can't remember if it's a cutler-hammer or whatever.I'm the owner-builder so chances are I'll just bypass the thing after final inspection - the circuit is already protected by a regular panel breaker before the AFCI. The 'bedroom' isn't even being used as a bedroom - it's really an upstairs bonus room (no closets) but because it has a 1/2 bathroom inside it, the city plan checkers in their wisdom said it has to be classed as a bedroom!
    HI Neil

    Lets explore this a tad more before we close the books. If there are receptacles in the bath they need gfci on a 20 amp branch circuit . But I think you probably know that. I'm curious though if you had the afci breaker also protecting the bathroom receptacles. If so you need to get any receptacles in that bathroom changed to gfci.

    As for the afci you have the neutral of the branch circuit connected to the afci breaker and the pigtail neutral of the afci connected to the neutral bar ... correct? Sorry if I am insulting your intellgence but you never now .. Don't take offense .. it likely is wired correctly since it works with other than motor loads.

    I'm also understanding that your sub-panel has just the afci breaker in it. Is the sub -panel 120 volt only or did you use a 120/240 volt double pole breaker to protect a 4 wire feeder to the sub-panel?


  8. #8
    Neil Hunter's Avatar
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    Default Re: Universal Motors on AFCI circuits

    Hi Roger,
    The bathroom 20A circuit is part of the AFCI protected branch circuit and there is already a GFCI in the bathroom which is required. (as you know, the AFCI does not protect against ground faults unless it's a combo).

    The AFCI is connected as you stated.

    The subpanel does only have an AFCI in it and is 120V only. Although the pigtail neutral is correctly connected to the neutral bar in the subpanel, the neutral bar in the subpanel is connected back to the main panel neutral bar via a dedicated wire but over a distance of maybe 10-12ft. I don't believe that should make any difference but correct me if I'm wrong. There are no shared neutrals anywhere in the house.

    Bottom line is I think the AFCI is just over-sensitive


  9. #9
    Roger Frazee's Avatar
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    Default Re: Universal Motors on AFCI circuits

    Hi Roger

    The bathroom 20A circuit is part of the AFCI protected branch circuit and there is already a GFCI in the bathroom which is required. (as you know, the AFCI does not protect against ground faults unless it's a combo).
    Yes .. I am just wanting to make sure I see the total 'picture' if you will. Ok .. speaking about the bathroom and electrical code. The bathroom receptacles are required to be on a 20 amp branch circuit and gfci protected.. That branch circuit cannot leave that bathroom to serve an other outlets outside the bathroom. So you cannot have bedroom receptacles or lights for the bedroom on the bathroom receptacle branch circuit. Which was why I was asking about how you had the afci wired and what it was protecting. I guess what I'm saying is the bedroom outlets must be afci but you cannot extend the bedroom branch circuit to the bathroom gfci receptacle(s), those must be served by their own 20 amp branch circuit. This is a pretty strict requirement.

    The AFCI is connected as you stated
    .

    I figured it was but need to have my peace of mind....

    You have your required smoke detector ?

    Well you may have a problem with the way the sub is wired.. I am assuming by dedicated wire from the neutral you mean an nm-b (romex) cable from the service equipment (main panel) to the sub-panel. So I'm picturing a single pole twenty amp breaker in the main and a nm-b #12 with ground ran to the bedroom sub -panel and the sub-panel then wired for 120 volts only.

    If by dedicated wire from the neutral bar in the sub panel to the neutral bar of the main panel you mean an individual (single) wire ran by itself then you have another problem and this would be a big violation of code.

    You may want to give me more detail on what you did to wire the sub panel for the bedroom because I'm not sure at this point....

    Another big question is ... do you have the neutral and ground separated in that sub-panel ? If not you need to get this done or you have a serious code violation. What I'm saying is you cannot have the neutral (white) and the bare ground wires connected to the same terminal bar in the sub-panel. You must have a separate grounding bar bonded to the case of the subpanel and your bare grounds connected to it. This is to keep neutral current from using the ground wire and the neutral wire as it returns to the utility transformer. It should only use the neutral for that purpose.. At the Service Equipment (your calling it the main panel) this is a different story and neutral and ground wires must be bonded together.

    Bottom line is I think the AFCI is just over-sensitive
    Who knows but lets get the sub panel wired correctly before we get too confident ..

    Last edited by Roger Frazee; 01-15-2010 at 04:28 PM.

  10. #10
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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Roger Frazee View Post
    Many local areas still are not adopting the new afci requirements of the NEC. This is an all to often issue with afci protected circuits and a huge headache for the contractors and homeowners.
    Quote Originally Posted by Neil Hunter View Post
    I totally agree with your comments. I think it is a ridiculous requirement especially in new construction using all copper wiring and correctly installed.
    People said the same thing about GFCIs when they first came out. In fact many electricians would install the GFCI to pass inspection and then go back and replace with non-GFCI protection, throwing the GFCI device into the trash. This practice continued EVEN AFTER the initial problems with GFCI were correct - once bad habits are acquired they are even harder to break.

    Apparently some here, many here, are too young to remember that happened when GFCIs first came out, yet those same people would not think of doing that today.

    I fully expect that cycle to repeat itself with AFCIs.

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  11. #11
    Neil Hunter's Avatar
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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Roger Frazee View Post
    Yes .. I am just wanting to make sure I see the total 'picture' if you will. Ok .. speaking about the bathroom and electrical code. The bathroom receptacles are required to be on a 20 amp branch circuit and gfci protected.. That branch circuit cannot leave that bathroom to serve an other outlets outside the bathroom. So you cannot have bedroom receptacles or lights for the bedroom on the bathroom receptacle branch circuit. Which was why I was asking about how you had the afci wired and what it was protecting. I guess what I'm saying is the bedroom outlets must be afci but you cannot extend the bedroom branch circuit to the bathroom gfci receptacle(s), those must be served by their own 20 amp branch circuit. This is a pretty strict requirement.
    Sorry - I misstated - the bathroom IS on a separate circuit. All the rough electricals were passed by the city inspector some time ago.

    I figured it was but need to have my peace of mind....

    You have your required smoke detector ?
    Yes - all smoke detectors wired in tandem so if one goes off, they all do (code requirement).

    Well you may have a problem with the way the sub is wired.. I am assuming by dedicated wire from the neutral you mean an nm-b (romex) cable from the service equipment (main panel) to the sub-panel. So I'm picturing a single pole twenty amp breaker in the main and a nm-b #12 with ground ran to the bedroom sub -panel and the sub-panel then wired for 120 volts only.

    If by dedicated wire from the neutral bar in the sub panel to the neutral bar of the main panel you mean an individual (single) wire ran by itself then you have another problem and this would be a big violation of code.
    Not a single wire but #12 white/black run through steel conduit from service equipment to subpanel

    You may want to give me more detail on what you did to wire the sub panel for the bedroom because I'm not sure at this point....

    Another big question is ... do you have the neutral and ground separated in that sub-panel ? If not you need to get this done or you have a serious code violation. What I'm saying is you cannot have the neutral (white) and the bare ground wires connected to the same terminal bar in the sub-panel. You must have a separate grounding bar bonded to the case of the subpanel and your bare grounds connected to it. This is to keep neutral current from using the ground wire and the neutral wire as it returns to the utility transformer. It should only use the neutral for that purpose.. At the Service Equipment (your calling it the main panel) this is a different story and neutral and ground wires must be bonded together.
    Neutral and ground are separate at the subpanel. There is a separate bar bonded to the case of the subpanel and incoming and outgoing ground wires are connected to it. The only place the neutral and ground are connected is at the service equipment.


  12. #12
    Roger Frazee's Avatar
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    Default Re: Universal Motors on AFCI circuits

    Very good .. sounds like your wiring is fine and inspected. So now I guess you decide what to do with the afci ....


  13. #13
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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Jerry Peck View Post
    People said the same thing about GFCIs when they first came out. In fact many electricians would install the GFCI to pass inspection and then go back and replace with non-GFCI protection, throwing the GFCI device into the trash. This practice continued EVEN AFTER the initial problems with GFCI were correct - once bad habits are acquired they are even harder to break.

    Apparently some here, many here, are too young to remember that happened when GFCIs first came out, yet those same people would not think of doing that today.

    I fully expect that cycle to repeat itself with AFCIs.
    I suspect your going to win that bet .. but I don't think the embracement of afci will occur for quite a few more years and only if they can fix the issues with the darn things.What I am seeing now is serious consideration about not continuing local code requirement for afci due to the tripping problems with the devices. It is way far and above the issues we had with gfci. In fact, due to a personal experience, I think the afci breaker should come with instructions to not plug oxygen equipment into an afci circuit. This was an issue with my father who has lung disease. No point in going into details I think you can figure it out.

    I hope that afci has the outcome that gfci had as this will save millions in property damage and undoubtably will save lives. I just don't think the consumer should be the one to foot their research cost by being the guinea pig.

    GFCI's still have an achilles heal in that they do need testing done by the homeowner a recommended once a month. I don't think that is happening.... I had to chuckle the other day when I read that several hundred dollars of tropical fish died due to a gfci trip. I'd bet the gfci operated as it was supposed to and most people if they owned those fish would probably use a circuit that ws not gfci protected from then on .. not realizing that the gfci very likely may have saved them from a potentially fatal shock.


  14. #14
    A.D. Miller's Avatar
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    Default Re: Universal Motors on AFCI circuits

    I just don't think the consumer should be the one to foot their research cost by being the guinea pig.
    RF: In a capitalistic society, who then?

    GFCI's still have an achilles heal in that they do need testing done by the homeowner a recommended once a month.
    RF: I do not think you are considering the vast array; that almost endless list of items in houses which require periodic oversight by homeowners.

    Last edited by A.D. Miller; 01-16-2010 at 08:20 AM.

  15. #15
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    Default Re: Universal Motors on AFCI circuits

    An AFCI combo breaker can trip for a reason other than an Arc Fault - i.e. if you're supplying this bonus room/bedroom with a single circuit - and the breaker trips in your remote panel - you may be exceeding/spikeing out when you plug in your motor load.

    I'm going to guess you have a lot of entertainment devices/power supplies already plugged in at the bonus room - even if off/standby mode they're likely still drawing current.

    Why a remote panel for a single 120 circuit 10-12 feet away? I could see if within six feet and you ran out of room in the first panel or if the first was not compatible with Arc-fault breakers.

    Voltage drops/resistance can be substantial even with short distance but multi connections in 120 VAC circuits.

    What is the size of the addition? What were the load calculations? I'd suspect you'd need at least three circuits - one for the half bathroom, one for stair lighting/etc possibly combined with some convenience receptacles with low anticipated use; and another for your entertainment devices.

    One thing that can really go "wrong" is certain laser printers even in standby mode combined with another motor load can trip many of those laser printers cannot be plugged into a "surge protection" strip or surge/battery backup device either - have you got a computer & printer set up in the bonus room?

    Did you wire your receptacles "feed through" or did you pig tail them?


  16. #16
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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Neil Hunter View Post
    I have a recently completed bedroom addition protected by a single AFCI in a separate subpanel. I cannot plug in anything with a universal motor (vaccuum cleaner, hair dryer etc.) since the arcing at the motor brushes immediately trips the AFCI breaker. Any other appliances work just fine. While this behavior makes sense, it seems the requirement severely restricts the use of certain appliances or is my breaker just over sensitive?
    Quote Originally Posted by Neil Hunter View Post
    I've still to check electrically but physically all looks good. Thanks for the suggestion.
    Quote Originally Posted by Neil Hunter View Post
    Roger: Code here requires them for bedrooms. I totally agree with your comments. I think it is a ridiculous requirement especially in new construction using all copper wiring and correctly installed. I need to check the mfgr of the breaker when I get home - can't remember if it's a cutler-hammer or whatever.I'm the owner-builder so chances are I'll just bypass the thing after final inspection - the circuit is already protected by a regular panel breaker before the AFCI. The 'bedroom' isn't even being used as a bedroom - it's really an upstairs bonus room (no closets) but because it has a 1/2 bathroom inside it, the city plan checkers in their wisdom said it has to be classed as a bedroom!
    Quote Originally Posted by Neil Hunter View Post
    Hi Roger,
    The bathroom 20A circuit is part of the AFCI protected branch circuit and there is already a GFCI in the bathroom which is required. (as you know, the AFCI does not protect against ground faults unless it's a combo).

    The AFCI is connected as you stated.

    The subpanel does only have an AFCI in it and is 120V only. Although the pigtail neutral is correctly connected to the neutral bar in the subpanel, the neutral bar in the subpanel is connected back to the main panel neutral bar via a dedicated wire but over a distance of maybe 10-12ft. I don't believe that should make any difference but correct me if I'm wrong. There are no shared neutrals anywhere in the house.

    Bottom line is I think the AFCI is just over-sensitive
    Quote Originally Posted by Neil Hunter View Post
    Sorry - I misstated - the bathroom IS on a separate circuit. All the rough electricals were passed by the city inspector some time ago.

    Yes - all smoke detectors wired in tandem so if one goes off, they all do (code requirement).

    Not a single wire but #12 white/black run through steel conduit from service equipment to subpanel

    Neutral and ground are separate at the subpanel. There is a separate bar bonded to the case of the subpanel and incoming and outgoing ground wires are connected to it. The only place the neutral and ground are connected is at the service equipment.
    I'm still confused on the bathroom/bonus room supply.

    The bathroom receptacles must be segregated - so how can it have a second circuit if there is only one breaker in your remote panel and all wiring is run from the remote panel feed by a 120 circuit?

    What about the lighting/fan for the half-bathroom - is it on the same circuit as the bathroom receptacle(s)? What else is being supplied by the circuit which supplies the receptacle(s) IN the half-bathroom off of the new bonus room?

    What are the voltages measured?

    Saying a rough-in electrical was passed means frankly nothing. The integrity of the circuit may have been compromised during finishing activities, for example.


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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Roger Frazee View Post
    I suspect your going to win that bet .. but I don't think the embracement of afci will occur for quite a few more years ...
    With GFCIs that took quite a few years too ...

    GFCIs came into the code in 1971, many electricians were still doing the 'install, get inspection, remove' thing into the mid-1980s - I doubt any electrician today still has that attitude.

    Similar to grounding and attaching grounding wires at light fixtures, switches, receptacles, etc., they simply did not believe it created enough of a safety feature to warrant connecting the ground wire they installed. That attitude went on until the the mid-1980s too - I doubt any electrician today has that attitude either.

    ... and only if they can fix the issues with the darn things.
    Yeah, that was the reason electricians kept pulling out the GFCIs they installed to pass inspection ... because the first GFCIs had a problem with nuisance tripping - partially a result of the GFCIs and partially a result of existing wiring practices at the time (my opinion).

    It took a good 15-20 YEARS for grounding to become fully accepted.

    It took a good 15 YEARS for GFCIs to become fully accepted.

    I would not look for AFCIs to become fully accepted for at least 15 YEARS either, and we have only just begun with AFCIs.

    Jerry Peck, Construction / Litigation Consultant
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  18. #18
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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Neil Hunter View Post
    First of all, I am not an inspector but a homeowner who has just completed an 1100sq ft addition single-handed including demolition and foundation work. While I didn't have any major corrections from the city inspectors, I always went round with the inspector during an inspection. The inspectors of course knew I was an 'owner-builder' and all the inspectors were more than willing to discuss any corrections with me as they arose during the inspection. I think it saved the inspector some time and also enabled me to see and understand the corrections so minimizing the possibility of corrections on corrections. I found the inspectors to be friendly, reasonable and professional. I never tried to be a know-all and was always aware that they do it for a living and not as a hobby!
    Something does not compute:

    Quote Originally Posted by Neil Hunter View Post
    I have a recently completed bedroom addition protected by a single AFCI in a separate subpanel. I cannot plug in anything with a universal motor (vaccuum cleaner, hair dryer etc.) since the arcing at the motor brushes immediately trips the AFCI breaker. Any other appliances work just fine. While this behavior makes sense, it seems the requirement severely restricts the use of certain appliances or is my breaker just over sensitive?
    Quote Originally Posted by Neil Hunter View Post
    Roger: Code here requires them for bedrooms. I totally agree with your comments. I think it is a ridiculous requirement especially in new construction using all copper wiring and correctly installed. I need to check the mfgr of the breaker when I get home - can't remember if it's a cutler-hammer or whatever.I'm the owner-builder so chances are I'll just bypass the thing after final inspection - the circuit is already protected by a regular panel breaker before the AFCI. The 'bedroom' isn't even being used as a bedroom - it's really an upstairs bonus room (no closets) but because it has a 1/2 bathroom inside it, the city plan checkers in their wisdom said it has to be classed as a bedroom!
    Quote Originally Posted by Neil Hunter View Post
    Hi Roger,
    The bathroom 20A circuit is part of the AFCI protected branch circuit and there is already a GFCI in the bathroom which is required. (as you know, the AFCI does not protect against ground faults unless it's a combo).

    The AFCI is connected as you stated.

    The subpanel does only have an AFCI in it and is 120V only. Although the pigtail neutral is correctly connected to the neutral bar in the subpanel, the neutral bar in the subpanel is connected back to the main panel neutral bar via a dedicated wire but over a distance of maybe 10-12ft. I don't believe that should make any difference but correct me if I'm wrong. There are no shared neutrals anywhere in the house.

    Bottom line is I think the AFCI is just over-sensitive
    Bottom line is something does not compute - 1100 sq. ft. addition, feeder panel 10-12 ft away from the "main" panel, only a 120VAC circuit not a 120/240 VAC feeder and a single 120VAC 20 amp circuit supplying the whole addition including the bathroom receptacle?

    Load calculations please. Distance/length of circuit what gauge wiring? Doesn't sound like a nusiance trip to me. A single 20 amp 120V circuit for 1100 sq. ft. would be very long, VD expected. When motors are starved for voltage they draw more current.

    Seems to me that combination ARC Fault Circuit Interupter/Circuit Breaker tripping when you're firing up the shop vac or whatever, is TELLING YOU SOMETHING. (ex. needing a 120/240 four wire feeder and balanced circuit loading - load calculations, etc.) 12 awg on single 120VAC 20 amp circuit likely undercalculated and not derated for 1100 sq. ft. with required lighting and continuous use requirements (125%) in addition to your convenience receptacles.

    Last edited by H.G. Watson, Sr.; 01-16-2010 at 08:47 AM.

  19. #19
    Fred Warner's Avatar
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    Default Re: Universal Motors on AFCI circuits

    Okay, I'm confused. New addition is 1,100 square feet. Table 220.12 NEC requires 3 watts per square foot for a dwelling. 3 times 1,100 equals 3,300 watts. If you take watts divided by voltage equals current W/E = I you end up 27.5 amperes on your one presumably 12/2 circuit. Was it a 12/3 run?


  20. #20
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    Default Re: Universal Motors on AFCI circuits

    OK. Let me try and clarify the whole situation with you all since you are only seeing part of the picture. There was a 550 sq ft addition in the same location as the new addition. The 550 sq ft addition was demolished and rebuilt with a second storey.The 1100 sq ft addition load calculations were done correctly before construction started. Starting at the service equipment here is what I have. The service equipment is on the outside wall of the garage and consists of the meter panel and a circuit breaker panel supplying the original house. On the inside wall of the garage behind the original breaker panel is a second service panel fed from the main supply after the meter and consists of circuit breakers that fed the orginal addition (240/120V). This panel had some breakers that were not used. The branch circuits to the addition are fed from this breaker box. The bathroom is fed from here on a dedicated circuit. The bathroom lighting is NOT on the same circuit as the bathroom outlet. The AFCI box is on the inside wall at the back of the garage next to the addition and is fed from the supply side of the inside panel (120V). Being inside the garage, steel conduit is used between the two panels. Hopefully this should answer some of your questions.

    Where I live, code enforcement is extremely strict and the city uses private architectural and construction companies for complete plan checks before a permit is issued. For that you must submit electrical load calculations, title 24 energy calcs, structural engineer calcs etc.etc. The city inspectors are also very strict and will not let anything go by..


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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Neil Hunter View Post
    The service equipment is on the outside wall of the garage and consists of the meter panel and a circuit breaker panel supplying the original house. On the inside wall of the garage behind the original breaker panel is a second service panel fed from the main supply after the meter and consists of circuit breakers that fed the orginal addition (240/120V).

    Whoa!

    You just stated you have two locations for service equipment and only one is allowed.

    Correct me if I am wrong, but what I think you meant to say was that the service equipment, including the main service disconnect, "is on the outside wall of the garage and consists of the meter panel and a circuit breaker panel supplying the original house". Then you meant to say that a new panel was installed on the inside wall of the garage which fed the original addition (and, presumably, the new second story addition?).

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  22. #22
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    Default Re: Universal Motors on AFCI circuits

    Yes. That is what I meant. I'm originally from the UK so some of my terminology may sometimes be wrong!


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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Neil Hunter View Post
    The branch circuits to the addition are fed from this breaker box. The bathroom is fed from here on a dedicated circuit. The bathroom lighting is NOT on the same circuit as the bathroom outlet.
    Okay, starting from the above, then ...

    The panel inside the garage is supplying the two additions, with one circuit (which is AFCI protected) supplying the bedroom area plus the bathroom lighting and exhaust fan, and another circuit supplying the bathroom receptacle outlet (which is GFCI protected - either as a GFCI breaker or a GFCI receptacle device).

    Good so far?

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  24. #24
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    Default Re: Universal Motors on AFCI circuits

    Almost! There is only one addition. The panel inside the garage supplies the addition. One circuit supplies the bedroom via an AFCI. Another circuit supplies the bathroom outlet with a local GFCI and another circuit supplies the bathroom lighting/fan


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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Neil Hunter View Post
    Almost! There is only one addition.
    I was calling it two additions as you said there was a single story addition which was deconstructed and a two story addition constructed in its place, which makes the "addition" the top floor, and the bottom floor not an "addition" but a total knock-down and rebuild remodel or alteration - as "addition" is defined as what it does ... "add" "additional" space to the structure.

    Anyway ...

    The bedroom is the second floor, and the first floor is ... ?

    The panel inside the garage supplies the addition. One circuit supplies the bedroom via an AFCI. Another circuit supplies the bathroom outlet with a local GFCI and another circuit supplies the bathroom lighting/fan
    Okay, 3 circuits to the second floor.

    How many to the first floor?

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  26. #26
    Roger Frazee's Avatar
    Roger Frazee Guest

    Default Re: Universal Motors on AFCI circuits

    Neil

    You now see why I was trying to get the ' total picture' it is not always cut and dry is it.... However knowing how you wired your additions likely is not going to solve your afci issue based on the problem as you explain it. The questions being asked may however uncover something we may have overlooked so bear with the onslaught of our inquiries.

    Being from the UK you have certainly done well with your owner/ contractor skills with a different electrical configuration in the USA. I spend a lot of time on a UK electrical forum learning how you do residential electrical installations in the United Kingdom. I've got files and files of information to that end. It is interesting the differences between consumer units, rcd's and other equipment as compared to what we use in equivalent situation here in the USA.

    It is not going to be easy to determine if the root cause is a bad afci or there is some other issue occurring when you operate a vacuum cleaner. I can tell you this I do not think you have some odd thing occurring that is tripping the afci due to some wiring error. If so in my opinion the afci would be opening the circuit regardless what you have plugged into it.

    This issue of vacuum cleaners not being liked by an afci is very well documented. I'm curious if you have any other afci's that you could exchange with the one that is tripping? Maybe you all ready said you did but I can't find that in the posts.

    I don't like it but unfortunetly you are code required to have the afci for that bedroom. So for me to say you should trash it was a overeaction to my dislike for the things. Bottom line is afci's are trouble free in many installations and should be fine no matter what vacuum or hair dryer you are using. It's just that they do tend to create giant headaches when you come across one that is tripping for no apparent reason other than motors. And this is very common with afci's.

    Whenever there is new construction about 9 out of 10 times when an issue with afci or gfci immediately surfaces it is due to an installation error or wiring fault. This is really what I first considered but I doubt it at this point because it appears to be just motor appliances that are tripping this afci. This can occur with gfci also and most of the time it is the fault of the appliance.

    Your problem seems to go a tad bit further in that it doesn't seem to matter what motor appliance you operate in that afci circuit ... plug a motor in and the afci trips. That's a tough one. I'd try a different afci if you haven't already. I don't like the devices but you should be able to have that afci operate correctly whether I like the darn things or not.

    In the back of my head I seem to remember that most of the problems with motors on afci were due to the old style afci not being a combination type. New code requires combination type so maybe check your afci to see if it is a combination type.

    I'm not up on any recalls unless this afci is not a combination type, back when those were being made there were some recalls for faulty devices. Might look into that if you can give us the manufacturer some one here may have information on recalls.

    Best I can do ... hope you get this worked out so the afci can be used ... good luck.

    Last edited by Roger Frazee; 01-16-2010 at 03:31 PM.

  27. #27
    Neil Hunter's Avatar
    Neil Hunter Guest

    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Jerry Peck View Post
    I was calling it two additions as you said there was a single story addition which was deconstructed and a two story addition constructed in its place, which makes the "addition" the top floor, and the bottom floor not an "addition" but a total knock-down and rebuild remodel or alteration - as "addition" is defined as what it does ... "add" "additional" space to the structure.

    Anyway ...

    The bedroom is the second floor, and the first floor is ... ?



    Okay, 3 circuits to the second floor.

    How many to the first floor?
    Two - outlets & lights


  28. #28
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    Default Re: Universal Motors on AFCI circuits

    Plugging the same vacuum cleaner and hair dryer into the bathroom GFCI protected receptacle does not trip that, correct?

    Plugging in anything else into the bedroom AFCI protected receptacles does not trip the AFCI breaker, correct?

    While it 'could be' the motors causing tripping of the AFCI breaker, it also 'could be' a nail or drywall screw through a wire which, when under start up load of the motor, draws sufficient current to heat a leakage condition to the point of allowing arcing temporarily during the initial higher current start up phase of motors - you could partially check this by plugging in a high wattage portable heater, heat gun, or lamp, with a high enough wattage to draw maximum current for the circuit and let it run for a while to allow for full heating of the conductor. That would be as close to a check as you could probably give it yourself.

    Before buying another AFCI breaker try this: move the AFCI breaker to another circuit, then try the vacuum cleaner and hair dryer on that circuit, then try one more. If both of those other circuit also lead to tripping of the AFCI, then it is likely the AFCI is the problem, however, if neither of those other circuits lead to tripping of the AFCI, then it is UNlikely the AFCI is the problem.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  29. #29
    Neil Hunter's Avatar
    Neil Hunter Guest

    Default Re: Universal Motors on AFCI circuits

    Well, I found the problem! The AFCI was actually working correctly. I just checked the wiring at the AFCI again and found that the load neutral connection coming out of the breaker hadn't been fully tightened. Plugging in a small charger or a lamp worked but as soon as I plugged in a higher power device such as a vacuum cleaner, the connection must have been arcing slightly and that combined with the vacuum cleaner motor tripped the breaker. I can now plug in vaccuum, hair dryer etc and they work just fine. All entirely my carelessness of course.

    Gentlemen thank you all for your help. I really appreciated all your advice and sorry if I wasted your time!

    Neil


  30. #30
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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by Neil Hunter View Post
    I really appreciated all your advice and sorry if I wasted your time!
    No waste of our time, the last couple of posts were in that very same direction anyway ...

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  31. #31
    Roger Frazee's Avatar
    Roger Frazee Guest

    Default Re: Universal Motors on AFCI circuits

    Hey I think it is great whenever something like this is solved. I don't consider it a waste of time because the solution is now filed away in my memory banks and it will surely be something I come across another day.

    Jerry was very close to analyzing what the cause was just not exactly possible to determine where it was located.

    This is what I meant earlier when I said an immediate issue after new construction almost always is an installation or wiring error.

    glad you are now able to stay code complaint ... I'm almost ready to be an advocate of afci...


  32. #32
    John Steinke's Avatar
    John Steinke Guest

    Default Re: Universal Motors on AFCI circuits

    Our friends at NEMA, and the NFPA, steadfastly maintain that there have been NO reports of properly functioning, listed appliances having nuisance trip problems with AFCI's.

    NEMA even has a form for such reports ... we need to DOCUMENT these failings. Heck, Fed Ex a report to the NFPA; while the time for comments has officially closed, MAKE them rejsect your report of such a problem.

    Enough such reports, and they might have to re-think this AFCI thing.


  33. #33
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    Default Re: Universal Motors on AFCI circuits

    Quote Originally Posted by John Steinke View Post
    Our friends at NEMA, and the NFPA, steadfastly maintain that there have been NO reports of properly functioning, listed appliances having nuisance trip problems with AFCI's.

    NEMA even has a form for such reports ... we need to DOCUMENT these failings. Heck, Fed Ex a report to the NFPA; while the time for comments has officially closed, MAKE them rejsect your report of such a problem.

    Enough such reports, and they might have to re-think this AFCI thing.
    And enough such cases ending as the one above did and maybe it will make believers of AFCI protection out of those who do not believe.

    As I said above, it will take time, and in the mean time there will be those who insist that there is no need to change, and not only no need, but that the change is negative in effect.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  34. #34
    Fred Warner's Avatar
    Fred Warner Guest

    Default Re: Universal Motors on AFCI circuits

    Long live the GF and AF circuit interrupters!! Bravo!! Bravo!!


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