Testing an AFCI by arcing wires, and the UL test

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First let me just say that I am no fan of AFCI's, but I really dont want this to turn into an anti-AFCI rant thread. I am just curious about these two things:

1. What is the counter-argument for why AFCI's never trip when you manually series arc the wire with a load?

2. UL 1699 covers AFCI's. Under "performance" they have "arc fault detection tests" which consists of:

40.1 General
40.2 Carbonized path arc ignition test
40.3 Carbonized path arc interruption test
40.4 Carbonized path arc clearing time test
40.5 Point contact arc test .
This is just from the table of contents I can view online. I dont have access to the full standard. Does anyone know anything more specific about these tests? I assume they are getting them to trip?

Has anyone done an "arc test" that got an AFCI to trip (besides a simple N-G connection)?
 

kwired

Electron manager
Location
NE Nebraska
First let me just say that I am no fan of AFCI's, but I really dont want this to turn into an anti-AFCI rant thread. I am just curious about these two things:

1. What is the counter-argument for why AFCI's never trip when you manually series arc the wire with a load?

2. UL 1699 covers AFCI's. Under "performance" they have "arc fault detection tests" which consists of:


This is just from the table of contents I can view online. I dont have access to the full standard. Does anyone know anything more specific about these tests? I assume they are getting them to trip?

Has anyone done an "arc test" that got an AFCI to trip (besides a simple N-G connection)?

And confirmed it tripped on AFCI functions and not thermal-mag functions.

They don't want us to understand these things, that may not be good for them in the end.

I think you need to have current over a certain level before it even will trip on AFCI function on combination type anyway, might be different level for series vs parallel fault detection.
 
I doubt UL is part of some broad conspiracy to push AFCI, so I assume they are testing them with some standardized procedure where they are confirmed to "detect arcs" or at least the arc in the test. I am just trying to understand how it works. I think they are only tested for functionality, and there isnt some specific "signature, voltage/current, or transient behavior that is programmed as standard - can someone confirm this?

RELEASE THE FULL UNREDACTED UL REPORT :lol:
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
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retired electrician
One of the things is that the AFCI does not look for a series arc if the circuit current is below 5 amps. It does not look for a parallel arc if the circuit current is below 75 amps.
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
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Retired PV System Designer
One of the things is that the AFCI does not look for a series arc if the circuit current is below 5 amps. It does not look for a parallel arc if the circuit current is below 75 amps.
Which means, basically, that to do a wire touching test for series arc detection, you really need to have a constant resistive load in parallel with the load that your are interrupting. And there is no practical way the home experimenter can test for parallel arc detection without tripping the mag or thermal function instead. The sole practical function of the parallel arc detection is to provide an almost instantaneous clearing time for some faults that do not trigger the mag trip. Without the parallel arc detection the fault would last until the thermal trip time elapsed.
European breakers simply lower the mag trip threshold instead, which combined with GF detection seems to be very successful in preventing fire ignition.
 

romex jockey

Senior Member
Location
Vermont
Occupation
electrician
First let me just say that I am no fan of AFCI's, but I really dont want this to turn into an anti-AFCI rant thread. I am just curious about these two things:

1. What is the counter-argument for why AFCI's never trip when you manually series arc the wire with a load?

2. UL 1699 covers AFCI's. Under "performance" they have "arc fault detection tests" which consists of:


This is just from the table of contents I can view online. I dont have access to the full standard. Does anyone know anything more specific about these tests? I assume they are getting them to trip?

Has anyone done an "arc test" that got an AFCI to trip (besides a simple N-G connection)?

The original nema afci task force was led by a Dr Joe Engle , i'm sure most are aware of his '12 dissertation to the IEEE> http://combinationafci.com/resources/doc_ieee_combination_afci.pdf

The group was divided and broke up over the UL simulator>>>

eOF06wB.jpg


This device introduced 15KV into a piece of zip cord,which a cut was made into, and then wrapped in flamable tape

Thus essentially 'series arc' passed muster

Basically, UL (because this was a joint mission, UL, CSPC,& NEMA) created a standard (as opposed to testing toward one)

This is public knowledge , it was also CMP-2 rop knowledge

~RJ~
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
1. What is the counter-argument for why AFCI's never trip when you manually series arc the wire with a load?


That you are breaking load much like a switch and its not really a sustained (dangerous) arc- AFCIs are designed to tell the difference between switching and arc faults.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
One of the things is that the AFCI does not look for a series arc if the circuit current is below 5 amps. It does not look for a parallel arc if the circuit current is below 75 amps.
That's insane! :eek:hmy: I have even less confidence than before -- and that was zero!
 

ramsy

Roger Ruhle dba NoFixNoPay
Location
LA basin, CA
Occupation
Service Electrician 2020 NEC
One of the things is that the AFCI does not look for a series arc if the circuit current is below 5 amps. It does not look for a parallel arc if the circuit current is below 75 amps.

You are quoting fake news.

When an AFCI breaker trips in the field, it often trips several adjacent AFCI breakers, which also need reset.
The adjacent breakers often have no load, much less 5, or 75 amps.
 

peter d

Senior Member
Location
New England
With a dual function breaker, the GFCI portion will do most of the important work anyway, masking the truly worthless nature of the AFCI portion.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
That doesn't give me much confidence knowing there is that large a blank spot in their functionality.


The argument UL will make is that parallel arc faults are not found below 75 amps as this is the lowest amount of fault current one can reasonably expect in a dwelling unit.
 

kwired

Electron manager
Location
NE Nebraska
I doubt UL is part of some broad conspiracy to push AFCI, so I assume they are testing them with some standardized procedure where they are confirmed to "detect arcs" or at least the arc in the test. I am just trying to understand how it works. I think they are only tested for functionality, and there isnt some specific "signature, voltage/current, or transient behavior that is programmed as standard - can someone confirm this?

RELEASE THE FULL UNREDACTED UL REPORT :lol:
UL isn't exactly what some think it is either. You want a product tested, they are going to ask what you want it tested for.

Certain things have a UL standard, you must meet those standards to get certain listings. UL doesn't necessarily come up with those standards all by themselves. Where will AFCI standards come from - probably the AFCI manufacturers, nobody else has much interest to even be involved with such standards.
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
UL isn't exactly what some think it is either. You want a product tested, they are going to ask what you want it tested for.

Certain things have a UL standard, you must meet those standards to get certain listings. UL doesn't necessarily come up with those standards all by themselves. Where will AFCI standards come from - probably the AFCI manufacturers, nobody else has much interest to even be involved with such standards.

Good point. I've always thought that UL existed to test products for safety and to that end they came up with the standards. How is this anything like that? Sounds to me like the AFCI manufacturers pay UL to test their products so they can look legitimate, to standards that the manufacturers come up with.

This is all starting to make even more sense now! This really needs a Mueller investigation!

-Hal
 

romex jockey

Senior Member
Location
Vermont
Occupation
electrician
UL, CSPC & NEMA are a consortium ,along with CMP-2 seats and/or alternates for the last 20 years.

read Joe Engle, yes it's long but the history is accurate.

~RJ~
 
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