ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Recent Posts
Danish type K Sockets
by winston_1 - 10/25/21 07:30 PM
Flexible Conduit?
by gfretwell - 10/24/21 01:59 AM
May I backfeed 3 phase transformer?
by dsk - 10/22/21 04:37 AM
Wire sizing
by gfretwell - 10/21/21 10:12 PM
GFCI's pops in large numbers
by dsk - 10/21/21 02:03 AM
New in the Gallery:
240/208 to a house
240/208 to a house
by wa2ise, October 9
Now you know.
Now you know.
by Tom_Horne, September 7
Who's Online Now
0 members (), 19 guests, and 20 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
#74432 01/21/07 07:06 PM
Joined: Jan 2005
Posts: 5,316
Cat Servant
I was just looking at another NEC forum, and I suddenly realized that the NFPA (the author of the NEC) has dropped the ball pretty badly, at least twice.

The first instance was the advent of the internet. By all rights, the premier electrical ought to be one started by the NFPA ... and not a few put up by dedicated electricians. When they finally did start up an electrical chat ... well, when was the last time YOU were there?

The second relates to the qualifications of electrical trades. First, let me pont out a few examples:
The NRA, a private group, has established a virtual monopoly on the qualification of firearms instructors.
The Red Cross has a similar strong presence in First Aid and Swimmng certification.
Even the NFPA has a strong role in firefighter training, as well as determining the actual "business practices" of Fire Departments.

So who certifies electricians? Here in Reno, we are changing over to "ICC" issued Journeyman cards. These cards will be accepted anywhere ICC codes are adopted.
This is ironic, as the ICC defers to the NEC on electrical matters. Building code, Fire code, etc., are under their umbrella.

I suppose the next failing of the NFPA will be the loss of credibility to its' NEC. Can this happen? Well, looking at the recent spate of "manufacturer driven" code changes, the NEC no longer gets the respect it once did.

Joined: Aug 2001
Posts: 459
Like you and I have discussed before John the Code seems to be getting less grounded in common sense.

Like the requirement for a seperate circuit for a range hood that is cord and plug connected, but not if hard wired. Or how many times is a breaker lockout really needed so when you change out a dishwasher no one turns on the breaker. Even the builders grade model in my townhouse lasted 15 years. I moved before it needed to be replaced. Is a lockout required for those electric hand dryers in the restrooms? I would think they get changed more than a dishwasher.

There are some that have changed during the recent Code cycles like where only grade level receptacles needed GFI protection and balconies didn't. I guess people never went outside after a rainstorm to listen to a radio.

Try finding a pool filter with a twist-lock plug from the manufacturer. I doubt you will, but that is what the Code calls for. Do you cut off the cord end to install the twist-lock and remove the UL listing?

Joined: Jan 2005
Posts: 109
Tripped over one of my pet peeves.....

AFCI's and Smoke detectors. Does the smoke detector circuit really "enter" the bedroom? Different inspectors interpret differently (surprise?).

Smoke detectors on seperate circuit? Not in my practice - tie 'em to something REAL obvious - lighting that's used every night. I want people to know if it has tripped....... Same with the Sump Pump in the basement - tie to the outside lights, not the basement freezer circuit (leads to lots of smelly food in a wet basement) - fixed one this spring.

And now, proposed GFI's everywhere? Proposal sponsored by manufacturers, or those of us who get faulty one's out of the box, or failures after short term usage....

I admit, I haven't done my homework on the proposal, but it smells like an AFCI......

Ever try to "field test" an AFCI? Plugging in a 2 HP contractor's saw with the on switch on, I guess doesn't draw an arc - just some sparks that burn off the tips of the plug..... Only "special" arc's qualify?

End rant..... bad Monday.....


Joined: Jul 2004
Posts: 9,669
Likes: 6
Grov, you have defined the weakness of the AFCI. It only detects parallel arcs (shorts to the neutral). A short to ground would activate the ground fault protection in an AFCI long before this gizmo figures out there is an arc.
It doesn't see a series arc at all. That is your saw, a loose breaker or the backstabbed receptacle with the aluminum wire your window shaker is plugged into.

Greg Fretwell
Joined: Jan 2007
Posts: 10
I am a bit new...can anyone explain how exactly an AFCI detects an arc? I know a GFI senses current differences between hot and neutral...but what characteristics of an arc does an AFCI look for?

Joined: Dec 2003
Posts: 751
well, not exactly.....but.....susposedly
the AFCI recognizes the characteristics of an arcing fault by electronic circuity that compares the signature of an arcing fault through memory chip technology. That's why it takes a little while to recognize the arcing fault. Which is not good for the dirty brushes on your skill saw (nuisance tripping), but should not pick up the arcing from closing a light switch.

Joined: Oct 2002
Posts: 482
Do you REALLY want to get me started on this whole thing about how the NEC is bowing to manufacturers at the expense of our profession? It's shameful. 'Nuff said...

Joined: Jul 2004
Posts: 9,669
Likes: 6
The arc in motor brushes and a plug being pulled are series arcs. The AFCI can't see those. It only detects a shorting arc and then at about 70a or so.

Greg Fretwell
Joined: Jan 2007
Posts: 10
70a? Wouldn't it usually trip from regular overcurrent protection than from an arc? I'm still a little confused as to how it works and the real practical benefit (ok an AFCI that does actually detect dangerous arcing...that is good, but if they really don't do that good of a job...)

Joined: Jun 2003
Posts: 1,143
AFCI protection of can lights in a bedroom, on a separate circuit from convenience outlets... especially since the selling point of AFCI adoption was faulty extension cords and space heaters...

[This message has been edited by DougW (edited 01-23-2007).]

Page 1 of 2 1 2

Link Copied to Clipboard

Tools for Electricians
Tools for Electricians

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman


Member Spotlight
dallas, texas, USA
Posts: 70
Joined: January 2002
Top Posters(30 Days)
dsk 7
Popular Topics(Views)
284,881 Are you busy
217,429 Re: Forum
203,743 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5