AFCI Tester

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GrayHeadedMule said:
While digging around on this site I ran across a AFCI tester that was actually published on this site.

http://www.mikeholt.com/news/archive/html/20/AFCI_Tester_08-16-2002.htm

Is this tester still around? Did it do what it claimed to do?

Anybody know of a testing procedure other than the test button on the breaker itself?
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There is no such thing as a true AFCI tester.

From the UL White Book:

OUTLET CIRCUIT TESTERS (QCYU)​
GENERAL​
This category covers portable devices with fixed attachment plug blades,
or probes attached to flexible leads, used to indicate various wiring conditions
in 15 or 20 A branch circuits by a pattern of lights or other similar
means along with markings or instructions to identify the probable wiring
conditions which cannot be determined by the tester.
The devices may include provisions for checking the functions of a
ground-fault circuit interrupter (GFCI) connected to the branch circuit, or
for indicating that a branch circuit is connected to an arc-fault circuit interrupter
(AFCI).
AFCI indicators operate by producing a waveform similar to an arc fault.
Since these devices cannot produce an actual arc fault, an AFCI indicator
may not trip every AFCI. AFCI indicators are provided with markings or
instructions that state the following or equivalent: ??​
​
​
​
CAUTION: AFCIs recognize
characteristics unique to arcing, and AFCI indicators produce characteristics
that mimic some forms of arcing. Therefore the indicator may provide
a false indication that the AFCI is not functioning properly. If this
occurs, recheck the operation of the AFCI using the test and reset buttons.
The AFCI button test function will demonstrate proper operation.??​

These devices are not intended for use as comprehensive diagnostic
instruments.
 
480sparky said:
From the UL White Book:
Click to expand...
Nicely stated 480.

I'm not an inspector, but, for the evaluation pre-bid and post-construction, I would love such an animal. Some here, at the Forum, think it is feasible, but, personally, after crawling around in Siemens' documenting of Arc Fault Detecting and Descrimination Techniques, in my personal opinion, I think the products will need to standardize on a common electronic interface that will permit a field electrician's computer to "talk" to the breaker, before we will arrive at anything direct, such as a GFCI tester. Until then, indirect analysis and faith is what we get.
 
What I see as the problem is the fact that these testers are trying to conform to a standard that doesn't exist. No standard has been set at any level that these AFCI breakers must conform to. When the standard is set, (which I don't forsee), than we can move on. Where does the line need to be drawn? That's a very well unanswered question. IF a universal tester IS established it will be as big as a hand held scope and cost a very big chunk of change. How many of you will purchase such an animal? I say nill. We're left at using the test button, and if the guardian at the crosswalk doesn't work, we either troubleshoot or have to replace him/her if need be.
 
76nemo said:
What I see as the problem is the fact that these testers
are trying to conform to a standard that doesn't exist.
No standard has been set ...
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Nemo,
Right to the point!
No Standard Exists for exact measurement. :mad:

I have thought about using a 3K Ohm resistor just to draw some sparks.
But that would be "MY" standard, no one elses! :smile:
 
Thank you all for the replies.

What I can't understand is that they can make a test button on and AFCI that works but not an apparatus that will simulate what the test button does.

What does the test button actually do? Does it actually create a fault or does it just show that the breaker will trip? If it just shows the breaker will trip, why even have it?
 
GrayHeadedMule said:
Thank you all for the replies.

What I can't understand is that they can make a test button on and AFCI that works but not an apparatus that will simulate what the test button does.

What does the test button actually do? Does it actually create a fault or does it just show that the breaker will trip? If it just shows the breaker will trip, why even have it?
Click to expand...

Since you asked;
http://forums.mikeholt.com/showthread.php?t=111163

I have studied many documents including Siemen's document- "Arc Fault Detecting and Descrimination Techniques". In addition I have spent many hours analyzing and testing one particular manufacturers AFCI. To the point where I have defined and simulated an arc signature and used it to repeatedly and reliably trip an AFCI.


So in my opinion a true AFCI tester is totally possible if the market were there.

Manufacturers of AFCI's understand the signature required to trip the devices and so can a manufacturer of an AFCI tester.

The test button on the device I tested does not create a true arc. It simply tests its ability to discriminate the three high frequencies that are a part of a true arc signature.
 
al hildenbrand said:
in my personal opinion, I think the products will need to standardize on a common electronic interface that will permit a field electrician's computer to "talk" to the breaker, .
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great concept :wink:
 
ELA, thanks for posting the link to your investigation of AFCI's. Now if I just knew what all the big words mean!:-?

I'm just a country boy that grew up tearing things apart to see how they worked, still didn't understand what I looked at, tried putting it back together and had extra parts when I was finished!:confused:
 
GrayHeadedMule said:
I'm just a country boy that grew up tearing things apart to see how they worked, still didn't understand what I looked at, tried putting it back together and had extra parts when I was finished!:confused:
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:D
:cool:
You are capturing the heart of the matter, as I see it.

The signals that an AFCI responds to are shrouded behind each manufacturer's stonewalling of the information about their proprietary AFCI software and firmware. We, as the people working with the AFCI "in a real world installation", are, and consistantly have been, denied that intimate "hands on" knowledge of how they tick.

Our very job is putting things back together so they work! A component like an AFCI, that has a very wide range of signals that it responds to, deserves, at the very least, a thick and detailed manufacturer's manual covering all aspects of its exact behaviour and operation. Anyone can buy one with their new vehicle. . .

Reading that manual will be exactly like taking the thing apart, and still not understanding it, BUT, one is more capable having the experience of, and future referance to, the manual to further inform one's solving problems with an AFCI in a real circuit.

Leaving us, as the mechanics, only the glove compartment manual, or, worse yet, only the advertising, is just plain wrong.
 
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al hildenbrand said:
:D
:cool:
You are capturing the heart of the matter, as I see it.

The signals that an AFCI responds to are shrouded behind each manufacturer's stonewalling of the information about their proprietary AFCI software and firmware. We, as the people working with the AFCI "in a real world installation", are, and consistantly have been, denied that intimate "hands on" knowledge of how they tick.

Our very job is putting things back together so they work! A component like an AFCI, that has a very wide range of signals that it responds to, deserves, at the very least, a thick and detailed manufacturer's manual covering all aspects of its exact behaviour and operation. Anyone can buy one with their new vehicle. . .

Reading that manual will be exactly like taking the thing apart, and still not understanding it, BUT, one is more capable having the experience of, and future referance to, the manual to further inform one's solving problems with an AFCI in a real circuit.

Leaving us, as the mechanics, only the glove compartment manual, or, worse yet, only the advertising, is just plain wrong.
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Well said Al,
I appreciate comments such as that much better than a constant regurgitation of "

"There is no such thing as a true AFCI tester.

From the UL White Book:
...."

Both the manufacturers and UL should be supporting better tools for diagnosing AFCI issues.
 
GrayHeadedMule said:
ELA, thanks for posting the link to your investigation of AFCI's. Now if I just knew what all the big words mean!:-?
Click to expand...


Sorry about that ...
I got into investigating these devices because I wanted to learn more about them and to convince -at least myself that they could be tested by an external device.
All the data aside the point I was trying to make is that the internal test switch does not do a very thorough job of testing the device. I believe the manufacturer relies on thorough testing at the time of manufacture (or at least I hope so) to catch any major faults with each unit.
After they are shipped into the field then the test switch does a "partial operational check".

So an external test device could do a much more thorough test.

I would love to know more about what type of production testing these units go through before they ship. I am willing to bet that they do not simply press the test switch. It is also hard to believe that each unit is subjected to the full UL1699 (actual electric arc fault testing).
My guess is that they have an external electronic tester that tests each unit. :cool:
 
Ela,

Can we have a "a true arc signature",
or are we heading towards a "standardized arc signature"?

Just a comment on terminology. :smile:
 
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Ela,

Are you saying that there is "actual electric arc fault" signature?

IMO,
UL may use the term 'arc fault signature', but that does not make it real.
UL may have a problem defining the rull range of arc fault signals,
although I could see them defining a small range of arc fault signals,
to be used as a 'typical' signal for testing purposes.

IMO, in the real world, any arc that ultimately causes a problem,
should be considered within the range of arc fault signals.
My thought is that Arc Faults come in a wide range of waveform 'signatures'.

IMO, as a humble opinion in the face of real world signals,
A general type of signal might be called an arc fault signature,
but to define any "single" waveform as "the" arc fault signature is problematic.

:smile:
 
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glene77is said:
to define any "single" waveform as "the" arc fault signature is problematic.
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Nicely synopsized. :smile:

And, I would submit, even a selection of several different waveforms chosen to represent "the" arc fault signature is problematic.

I think, that along with the common electronic interface, supporting field electrician held computer "conversations" with the breaker about its activities, comes the ability to apply manufacturer software updates to the device, and comes the ability to inject test signals at additional points along the AFCI block diagram.
 
glene77is said:
I have thought about using a 3K Ohm resistor just to draw some sparks.
But that would be "MY" standard, no one elses! :smile:
Click to expand...

Sorry Glene77,
I just could not get past this one....

Were you talking about a GFCI? vs an AFCI ? ;)

Yes arc signatures vary. They all have common charactoristics that can be identified and replicated. It would be no problem to build a tester that replicated each manufacturers requirements in order to trip their breaker.

Think about this a little more. If each manufacturers signatures are unique, and they do not have common charactoristics that can be isolated and detected, then are they really protecting the circuits they are installed in?

I contend that if an external AFCI tester, that is able to trip any and all manufacturers breakers, cannot be built, then AFCI's should never be required to be installed as they are not truely protecting the circuit properly.
 
ELA said:
I contend that if an external AFCI tester, that is able to trip any and all manufacturers breakers, cannot be built, then AFCI's should never be required to be installed as they are not truely protecting the circuit properly.
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:cool:

Wicked!
 
ELA said:
I contend that if an external AFCI tester, that is able to trip any and all manufacturers breakers, cannot be built, then AFCI's should never be required to be installed as they are not truely protecting the circuit properly.
Click to expand...

AFCI is truly a "hard" problem - not like GFCI. And given the current state of AFCI, I think you have a very interesting point (though "never" is a pretty strong word). What are the listing requirements for AFCI? Is there a "test arc" that they must trip on to prove that they really do anything? Are manufactures required to disclose anything about the algorithms they use to detect arcs? How can we know we aren't just being ripped off if there isn't anything that can be used to even show that one works properly? Anyone here work on AFCIs design and care to comment?
 
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