ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat Box
Recent Posts
New tool
by gfretwell - 10/24/20 11:09 AM
Where is Everyone?
by Bill Addiss - 10/17/20 07:04 PM
Beyond Belief
by gfretwell - 09/27/20 12:03 AM
New in the Gallery:
Facebook follies, bad wiring
FPE in Germany pt.2
Who's Online Now
1 registered members (Scott35), 16 guests, and 18 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 3 1 2 3
AFCI breakers #4063 09/09/01 01:42 PM
Joined: Aug 2001
Posts: 7,520
P
pauluk Offline OP
Member
I've been reading some of your older messages about provision of AFCIs. This is quite fascinating as we don't have anything like these breakers over here (not yet anyway!).

Does anyone know exactly how these devices work?

Work Gear for Electricians and the Trades
Re: AFCI breakers #4064 09/09/01 08:29 PM
Joined: Oct 2000
Posts: 5,389
S
sparky Offline
Member
http://www.zlan.com/arc.htm

Paul;
they sense an arc of (i believe) 75W or more

.......have you ever heard the expression 'tail waggin' the dog'???
[Linked Image]

[This message has been edited by sparky (edited 09-09-2001).]

Re: AFCI breakers #4065 09/10/01 08:17 AM
Joined: Aug 2001
Posts: 7,520
P
pauluk Offline OP
Member
Thanks for the link. I figured they'd obviously have to be more complex than the standard thermal/magnetic or even amplified GFI types.

The only way I can see for them to work is for the circuitry to look for short pulses of increased current but not trip on longer pulses. I can see how such a circuit could be developed with simple op-amps etc. in integrated form, though I wouldn't be surprised if they actually use a micro-controller to analyze the current pulses.

I just wondered if any more technical details on the actual arrangement were available.

Does the AFI rely on the control circuitry to trip on normal overcurrent, or does it incorporate a normal thermal/magnetic trip as a backup?

Quote
Originally posted by sparky:

.......have you ever heard the expression 'tail waggin' the dog'???

Most definitely!

Re: AFCI breakers #4066 09/10/01 06:14 PM
Joined: Oct 2000
Posts: 5,389
S
sparky Offline
Member
http://www.zlan.com/afci_c4.htm

Paul,
i could'nt really answer any of your Q's , this (check pix in link) is definitly not my forte' .

i'd like to know how to detect a bad AFCI

Re: AFCI breakers #4067 09/10/01 08:09 PM
Joined: Nov 2000
Posts: 2,236
sparky66wv Offline
Member
Steve,

No "test button" as per GFCI?

I've yet to get a close look at one of these buggers...

Guess the "pair of wires and a really steady hand" won't do it...

Great Q... Just how do we test them?

[Linked Image]

I suppose one could run a spot (read arc) light on an AFCI circuit (If you could find one that runs on 120V 20A) and provide a known safe long-lasting arc...

[This message has been edited by sparky66wv (edited 09-10-2001).]


-Virgil
Residential/Commercial Inspector
5 Star Inspections
Member IAEI
Re: AFCI breakers #4068 09/11/01 05:27 AM
Joined: Oct 2000
Posts: 5,389
S
sparky Offline
Member
Virgil;
yes there's a test button on the breaker itself, just like a GFI. I just haven't found a tester to plug in thoughout the circuit like the one's used for receptacles with the GFI tester.
where would i get a calculated arc of say, 76watts's [Linked Image]

Re: AFCI breakers #4069 09/11/01 04:53 PM
Joined: Jun 2001
Posts: 642
N
nesparky Offline
Member
Don't worry since this will be a problem sure the mahufacturers who got the code comitte to cram them down our throuts will soon have a expensive tester for us to buy.


ed
Re: AFCI breakers #4070 09/11/01 06:55 PM
Joined: Aug 2001
Posts: 7,520
P
pauluk Offline OP
Member
Quote
Originally posted by sparky66wv:

I've yet to get a close look at one of these buggers.

Now there's another word that has a somewhat different meaning on this side of the Atlantic!

Re: AFCI breakers #4071 09/11/01 07:01 PM
Joined: Aug 2001
Posts: 7,520
P
pauluk Offline OP
Member
Quote
Originally posted by sparky:
http://www.zlan.com/afci_c4.htm
Paul,
i could'nt really answer any of your Q's , this (check pix in link) is definitly not my forte' .
i'd like to know how to detect a bad AFCI

Thanks for that. The diagrams & notes on that site are very helpful. Looks as though as I was right about the microprocessor analyzing the current.

Did you follow the links there to the pages about testing an AFCI?

They seem to be using another micro-driven test unit which stores typical arc waveforms and then re-generates them to test the breaker, except it's done via the non-shunted neutral line only in order to keep the current down.

Re: AFCI breakers #4072 09/11/01 08:07 PM
Joined: Oct 2000
Posts: 5,389
S
sparky Offline
Member
http://www.zlan.com/testing/testing3.htm

well it certainly looks $$$$
[Linked Image]

Page 1 of 3 1 2 3

Featured:

2020 National Electrical Code
2020 National Electrical
Code (NEC)

* * * * * * *

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

 

Member Spotlight
noderaser
noderaser
Portland, Oregon, United States
Posts: 404
Joined: March 2007
Show All Member Profiles 
Top Posters(30 Days)
Popular Topics(Views)
271,004 Are you busy
205,006 Re: Forum
193,124 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.3