Is overkill a bad thing? Arc Fault and Ground Fault where not required?

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Electrician
Yes I realize a GFCI would have found the problems I described. My greater concern was and is arc faults in this older 1920's house. Electrified in the 1940's when REMC power became available.
I understand your concern but I don't think the AFCI will ease that concern as I haven't seen any proof that they work. Not a lab test but a real world arc that they detect. I know for sure they don't recognize a "glowing" connection, and from the videos I've seen they don't recognize a series arc either.
 

mbrooke

Senior Member
Location
United States
I understand your concern but I don't think the AFCI will ease that concern as I haven't seen any proof that they work. Not a lab test but a real world arc that they detect. I know for sure they don't recognize a "glowing" connection, and from the videos I've seen they don't recognize a series arc either.
The technology is to primitive to differentiate between normal and abnormal current signatures.
 

DanS26

Member
Location
IN
The technology is to primitive to differentiate between normal and abnormal current signatures.
Agree.

The vacuum sweeper tripping the AFCI circuit is a good example. Does not happen often but it is still annoying.

Another example is the ATS when operated will trip a couple of the AFCI's. Must be detecting the arc in the switch. Does not happen often but again annoying.
 

mbrooke

Senior Member
Location
United States
Agree.

The vacuum sweeper tripping the AFCI circuit is a good example. Does not happen often but it is still annoying.

Another example is the ATS when operated will trip a couple of the AFCI's. Must be detecting the arc in the switch. Does not happen often but again annoying.
And, when an arc fault does happen (assuming they do) how do we know the device will tell the difference between this dangerous arc and a vacuum cleaner?
 

kwired

Electron manager
Location
NE Nebraska
And, when an arc fault does happen (assuming they do) how do we know the device will tell the difference between this dangerous arc and a vacuum cleaner?
They happen, but many believe 120 volts AC is not enough to sustain such arcs for long enough duration to be a problem without additional activity to help maintain the arc. Like with a welder, one feeds material into the arc to replace what is consumed in the arc in order to maintain the arc. You also can't have too fast of arc response by the AFCI or simply opening a switch on a normal load will be an issue.
 

mbrooke

Senior Member
Location
United States
They happen, but many believe 120 volts AC is not enough to sustain such arcs for long enough duration to be a problem without additional activity to help maintain the arc. Like with a welder, one feeds material into the arc to replace what is consumed in the arc in order to maintain the arc. You also can't have too fast of arc response by the AFCI or simply opening a switch on a normal load will be an issue.
I agree, 120 volt can briefly arc or spark, but sustained arcing is just not possible under normal residential wiring conditions.
 

peter d

Senior Member
Location
New England
I would not spend a penny on AFCI protection. If I built a house out in the country with no permits and no inspections, I would not install AFCI protection at all.

I'm assuming it's understood that I meant my own house that I would live in. If it's for someone else, I would have no choice but to install the necessary AFCI protection. But where my own home and money are involved, there's no way that's happening. :happyno:
 

mbrooke

Senior Member
Location
United States
I'm assuming it's understood that I meant my own house that I would live in. If it's for someone else, I would have no choice but to install the necessary AFCI protection. But where my own home and money are involved, there's no way that's happening. :happyno:
If enough people speak out that can change.

As for my own home I took out a dozen AFCIs, megged the wiring and then put in standard thermal mags. Never been happier. :D:cool:
 

user 100

Senior Member
Location
texas
..... The neutral from old wiring was connected to both the neutral and the EGC of the romex creating the parallel path.

Second and third bootleg bonding were in light fixtures where again new and old wiring were combined. Someone just did not know what to do with that extra wire or understand its purpose.
Many old guys ( who get a pass in my book because many simply didn't know any better.:)) believed that in the absence of an egc that it was a good idea to repurpose the neutral as both egc and ccc - their reasoning was that "any type of egc with a solid connection to the source is better than none at all" and "well, gee, they are bonded together out in the panel, so whats the big deal anyways about tyin' 'em together anywhere else?" Of course, nowadays we know this is a big no-no.

Another culprit behind this type of "work" are hacks who will "touch up" an old install for flippers- make the outlets/devices "appear" to be grounded when tested by an inspector.
 

dfmischler

Senior Member
Location
Western NY
If you wanted to future-proof/overkill it some, some things I *might* do are:

~ 20A circuit where 15A would suffice.
~ Extra dedicated circuits where you might need them (RV outlet, EV recharging, shop air compressor, jacuzzi, etc), or perhaps a box and conduit stub to crawlspace.
~ Heavy-duty switches/receptacles
~ Interlocked smoke detectors
~ Putty pad boxes
~ Cable it for security, sound, cameras
~ LED lighting
When I built my house in 1998 I pulled Cat5 and RG6 cable to many places; I thought everywhere. I asked the EC to give me a 3/4" conduit from the basement to the attic "just in case", and I am glad I did. I pulled Cat5e through that conduit for one of the security cameras I installed this past year.
 

ddecart

Member
Good discussion guys, and thanks fore the bit of an education.

I would not spend a penny on AFCI protection. If I built a house out in the country with no permits and no inspections, I would not install AFCI protection at all.
I'll be kinda out in the sticks, but definitely not away from inspections & permits. The inspectors when I built my current house were total sticklers. Wire stapled 1/16" too close to the face of a stud? Failed. Same department for the next house.

If you wanted to future-proof/overkill it some, some things I *might* do are:

~ 20A circuit where 15A would suffice.
~ Extra dedicated circuits where you might need them (RV outlet, EV recharging, shop air compressor, jacuzzi, etc), or perhaps a box and conduit stub to crawlspace.
~ Heavy-duty switches/receptacles
~ Interlocked smoke detectors
~ Putty pad boxes
~ Cable it for security, sound, cameras
~ LED lighting

You *could* put in AFCI by the proposed codes of 2017; however I wouldnt. Perhaps by the time your area adopts that, newer/better tech will be out, or it will be less expensive than it is now.
I'd add to that emergency lighting in hallway, at the MDP and in the vicinity of wherever you keep your gun(s). Also smokes where the Christmas tree will be and over the dryer.
When I built my house in 1998 I pulled Cat5 and RG6 cable to many places; I thought everywhere. I asked the EC to give me a 3/4" conduit from the basement to the attic "just in case", and I am glad I did. I pulled Cat5e through that conduit for one of the security cameras I installed this past year.
Good suggestions. When I built my house in 2001, I ran about 1000' each of Cat5 and RG6, never thinking that hardly any of it would be used and I'd end up fishing a 50' HDMI cable to connect the TV and Receiver. Live & learn :)

I'm definitely thinking more 20A general purpose circuits is a good idea. It doesn't take too much of a change in room use to increase draw.
 
Top