2014 Disposals on Arc-Fault and GFCI

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jap

Senior Member
Occupation
Electrician
The best chance of preventing a fire from a poor connection is the GFP function of some GFCIs. The heat from the "glowing connection" will often melt enough insulation to cause a ground fault before it causes a fire. The GFP function is not required by the AFCI standard and at least one manufacturer has eliminated it.

That type of fault generally causes way more damage than a simple current leak to ground like most gfis tend to trip at.
 

mike1061

Senior Member
Location
Chicago
I would have had little problem with increased GFCI requirements in the NEC and no AFCI requirements, especially after hearing all the controversy that has been brought up over AFCI ever since they were introduced to NEC. Nobody really knows if they will do what they claim they will do, and those that claim they do know can't seem to prove it to others. The GFCI has proven it's benefits fairly well.


This is exactly how I feel. That and the fact I have had several problems with AFCI during construction and with homeowners plugging stuff in.
Thanks
Mike
 

PetrosA

Senior Member
oh, joy. then any nuisance trip simply shuts down the whole house?

and service upgrades to older houses that have three wire home runs...
those will require rewiring, at least to the extent of adding another run
so you don't have to share the neutral, yes?

the chief inspector for a city near here and i spent an hour trying to
get an AFCI to trip one morning, just out of curiosity.

there are two things that will make it trip for sure..... the test button
on the device, and the test button on the Ideal AFCI tester.

with a light bulb providing the load, i tried separating wires to produce an
arc under load..... i got a pretty decent arc going, could have gotten my
merit badge in fire making with it, for maybe 15 seconds, and that AFCI
was blissfully unaware of it.

i suspect the major result of the AFCI debacle will be to provide a flourishing
gray market in bootleg AFCI's, that don't do anything other than trip when
the test button is pressed. they will be made in china, just the same way
the bootleg circuit breakers are made now, and in the same factories,
by the same people.

usually when any regulatory body sets out to do something, the result is
the exact opposite of what the stated intention is.

and i think the main goal of the AFCI is to provide a generous bottom line
for NEMA manufacturers. that's the goal, not the stated intention, of course.

I'm not saying it's sensible, just that it would be more cost effective. If it gets to the point where AFCI breakers cost more than the entire service equipment (panel, meter socket, feeders and other breakers), customers will definitely take notice of that increase and possibly demand options.

Outside the US, split bus panels are popular just for this reason - you can put RCD protection on sub-groups of circuits so that the lights don't go out if a corded appliance has a GF in it. They're also starting to push AFCI breakers outside the US called AFDs. They're showing them on individual circuits rather than whole busbars and the push (for now) seems to be in public-use buildings, old age facilities, schools etc. and new construction, but I'll bet it won't take long to see the push for retrofit.
 

kwired

Electron manager
Location
NE Nebraska
That type of fault generally causes way more damage than a simple current leak to ground like most gfis tend to trip at.
Most of the time I find loose connections that have simply heated until an open circuit condition shuts the load down. But looking at all that had melted or considering what could happen if something combustible would be in close proximity, it is amazing there are not more fires then there are. Would enough current leak to trip a GFCI in many of those cases, IDK? May actually depend on how close in proximity an equipment grounding conductor is. A fault to the protected grounded conductor will not be seen as fault current to the GFCI and would have to reach overcurrent protection levels before there is any interruption by protective devices.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
That type of fault generally causes way more damage than a simple current leak to ground like most gfis tend to trip at.
That is correct, but there is no protective device on the market that directly detects that type of fault. The AFCI detects it if it progresses to a parallel arcing fault that has a fault current of at least 75 amps. It is very likely that any glowing connection or high resistance fault will cause enough damage to create a ground fault, and the GFP part of the AFCIs that still have that feature trip on 30 to 50 mA of ground fault. I stand by my statement that the most effective detection of this type of fault is ground fault detection.
 

jap

Senior Member
Occupation
Electrician
That is correct, but there is no protective device on the market that directly detects that type of fault. The AFCI detects it if it progresses to a parallel arcing fault that has a fault current of at least 75 amps. It is very likely that any glowing connection or high resistance fault will cause enough damage to create a ground fault, and the GFP part of the AFCIs that still have that feature trip on 30 to 50 mA of ground fault. I stand by my statement that the most effective detection of this type of fault is ground fault detection.

I agree , just saying theres a lot of difference between a full blown ground fault as your describing is fixing to happen, and a small 30 to 50 MA of current that gently trips the Ground Fault Protection Device.
 

crtemp

Senior Member
Location
Wa state
210.12 of the 2014 Code will require all 15 and 20-amp 120-volt outlets and devices (such as switches) to be on arc-fault protection, and this would include the garbage disposal. Even if it's hard-wired there's still a switch (device). Also if it's cord and plug connected it would have to be GFCI since the outlet is within 6' of the sink. Just wondered if anyone had thoughts or good or bad experience on this one?

Dishwashers and disposals only need to be gfci in other than dwelling units correct?
210.8(a)
(7) Sinks ? located in areas other than kitchens where receptacles are installed within 1.8 m (6 ft) of the outside edge of the sink
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
Dishwashers and disposals only need to be gfci in other than dwelling units correct?
210.8(a)
(7) Sinks ? located in areas other than kitchens where receptacles are installed within 1.8 m (6 ft) of the outside edge of the sink
There is a new section in the 2014 code.
(D) Kitchen Dishwasher Branch Circuit. GFCI protection shall be provided for outlets that supply dishwashers installed
in dwelling unit locations.
This rule applies to both cord and plug connected as well as hard wired dishwashers in dwelling unit kitchens. It would also apply to dishwashers that do not operate at 120 volts, if there are any.
 

kwired

Electron manager
Location
NE Nebraska
Would I need to gfci protect a hotwater toekick heater under the sink cabinet? It was be within the 6' .

If cord and plug connected - maybe - need more details.

If hard wired, no.

If other than 120 volts, no.

If 2014 code applies and it is 120 volts then AFCI is likely required, whether cord connected or hardwired.
 
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