'Proof' that AFCI devices really locate arcs.

[romex jockey]

Valid points User

Now if we ,as sparks, could engineer OCPD thermal magnitude towards any given circuit, meg it for validation before it's debut OR meg it all if age and degradation were obvious i'd wager a substantial percentage of electrical woes would be revealed

Instead, we have the magic widget marketed to deal with it all

~RJ~

 

[mivey]

I disagree, we already have these and no they aren't eating up box fill:

Wagos are not the same as what this guy proposed.

And thermal fuse technology isn't all that big

It is not a thermal fuse. It is a thermally-activated spring-loaded switch that creates a line-ground fault. Once the fault is created, the up-line breaker is supposed to trip and take out the source supply

Wouldn't be hard to put a thermal fuse in them.

Not what the inventor is proposing.

 

[mivey]

Can you give me your reasons?

A few that come to mind:
Need hot and ground at every monitored connection so upstream device can be ground-faulted.

Fill requirements with wirenuts would differ from a connector using a spring-loaded thermal switch with extra terminations.

Extra connections raise chances of failures.

Extra labor & cost.

Box packing method would have to change because of grouping including hot & ground.

Neutral repairs get more complicated as we must include other conductors.

Device size increases.

Increase in device complexity and failure modes.

Introduces a ground fault that depends on upstream device to clear.

Clearing device and path would require higher standard of verification due to introduction of a ground fault.

Perhaps a better connector is a better solution than monitoring weak connectors.

No wiring method would need to be changed

It would for what he proposed

it would simply be wago that automatically trips when a connection becomes dangerously hot.

I would prefer a better connection and then you could forgo the thermal sensor. Would not have to be thermite but perhaps more idiot-proof. Yes, we are dumbing down our industry because, at least for some of the cases, the idiots don't know how to make a proper connection. Another culprit is cheap devices.

 

[mivey]

Starting at 10:38, widget appears at 11:31. Yes its a bit bulky but keep in mind its a prototype

Glad you noticed how much bigger it is. Did you also notice the requirement that all of the wires be at the connector (so it can create a ground fault)? No more simple stand-alone neutral splices.

 

[mivey]

The device shown looks like it somehow triggers the breaker to trip. Perhaps as simple as creating an intentional (current limited???) ground fault if it overheats.

Yes. This particular configuration requires an up-stream GF breaker to work and since they can trip on low ground current they use a limiting resistor.

Without a GF breaker, they have to create a bigger ground fault. IIRC they always bring the ground to the connector but in one of the neutral-monitoring scenarios the over-heated neutral creates a line-ground fault (so the line conductor must also be present at the connection).

 

[user 100]

Valid points User

Now if we ,as sparks, could engineer OCPD thermal magnitude towards any given circuit, meg it for validation before it's debut OR meg it all if age and degradation were obvious i'd wager a substantial percentage of electrical woes would be revealed

Instead, we have the magic widget marketed to deal with it all

~RJ~

A multifaceted approach to prevent or address issues would do so much better than the singular catch-all located at the bc origin. The one big thing about the problem concerning poor terminations is that they are so easily remedied, taking out a excuse for the afcis existence. People are really worried about those loose terminations-why not lobby the insurance industry to give rebates to property owners to have a licensed guy come out once a year to do a check of their electrical system? That right there would benefit the trade enormously and would make homeowners safer.

 

[templdl]

Wagos are not the same as what this guy proposed.

It is not a thermal fuse. It is a thermally-activated spring-loaded switch that creates a line-ground fault. Once the fault is created, the up-line breaker is supposed to trip and take out the source supply

Not what the inventor is proposing.

One thing that I have always uderstood is to never intentionally overload a circuit with the expectation that a breaker will trip. This often happens with a holiday celebration when too many crockpots are plugged in with the expectation that, don't worry as the breaker we I'll trip on overload. And to never intentionally short circuit with the expectation that as breaker will trip.
The key word is intentional as now you are expecting a breaker to respond which it. I' m not saying that a breaker is unreliable because they are. But when a device downstream internationally causes a short circuit to for a breaker to trip that concerns me.

 

[user 100]

One thing that I have always uderstood is to never intentionally overload a circuit with the expectation that a breaker will trip. This often happens with a holiday celebration when too many crockpots are plugged in with the expectation that, don't worry as the breaker we I'll trip on overload. And to never intentionally short circuit with the expectation that as breaker will trip.
The key word is intentional as now you are expecting a breaker to respond which it. I' m not saying that a breaker is unreliable because they are. But when a device downstream internationally causes a short circuit to for a breaker to trip that concerns me.

Especially worrisome if the ocpd ahead of that device is an FPE red tip.hmy:

 

[templdl]

Can you get page 14 (16 in the viewer) to load?

I finally fired up my desktop. My printer printed up to p15 with the next page being blank. Although I could view the entire document It would not print past 15 and errored. I manually set the print request to print all the pages after the blank page 16 which worked.

 

[romex jockey]

A multifaceted approach to prevent or address issues would do so much better than the singular catch-all located at the bc origin. The one big thing about the problem concerning poor terminations is that they are so easily remedied, taking out a excuse for the afcis existence. People are really worried about those loose terminations-why not lobby the insurance industry to give rebates to property owners to have a licensed guy come out once a year to do a check of their electrical system? That right there would benefit the trade enormously and would make homeowners safer.

Yes User....

Yesterday we pulled a mile of BX out of an older mansion terminated like no self respecting member of our trade would have done past or present. Today we're off to repair a Home Depot installation gone wrong. Next week we have to clean up some 480V mess the maintenance man installed......

In a broader overview, bona fide sparks are a minority juxtaposed to overall electrical installs. Even my AHJ claims that maybe 5% of my turf has even seen an EI , and even then they've maybe time to inspect the obvious, dumb that down to lower standards for HI's

The NEC responds with codes for the above sorts, who will never read them

The market responds with products to protect their installs

Sadly, wag to dog rules here......

I would encourage anyone of similar sentiment to investigate foreign systems, and those respective sparks approach to them

~RJ~

 

[user 100]

Yes User....

Yesterday we pulled a mile of BX out of an older mansion terminated like no self respecting member of our trade would have done past or present. Today we're off to repair a Home Depot installation gone wrong. Next week we have to clean up some 480V mess the maintenance man installed......

In a broader overview, bona fide sparks are a minority juxtaposed to overall electrical installs. Even my AHJ claims that maybe 5% of my turf has even seen an EI , and even then they've maybe time to inspect the obvious, dumb that down to lower standards for HI's

The NEC responds with codes for the above sorts, who will never read them

The market responds with products to protect their installs

Sadly, wag to dog rules here......

I would encourage anyone of similar sentiment to investigate foreign systems, and those respective sparks approach to them

~RJ~

Thing of it is though alot of the ideas kicked around on this thread (self fusing splices,gfci all etc..) and the installation of the afci to protect older homes would require just as much, if not more qualified persons in order to be safely installed as the rebate idea would. Maybe I am a little too old school, but I certainly feel much better that a set of trained eyeballs would be looking at vintage terminations vs. afci and pray. As for new installations and the need for rules to protect those brand new but arcing schemes that result from 2nd rate work-wag the dog indeed. The inspections for existing installations could consist of (get ready for trade blasphemy here) only checking terminations/and splices behind faceplates and basically just fix what would be an immediate hazard (loose wires at recs, switches, loose wirenuts etc), not exactly something requiring advanced skill.

 

[peter d]

I'm completely against thermal fusing or whatever it is at terminations. That's just another useless gimmick to protect the unqualified.

 

[K8MHZ]

I'm completely against thermal fusing or whatever it is at terminations. That's just another useless gimmick to protect the unqualified.

I am against them as well, seeing how they operate.

As it appears, the devices short all conductors together when the temperature reaches a certain level. Then, the OCPD is supposed to trip, removing energy from the circuit.

What if the device fuses and the breaker doesn't trip?

 

[mbrooke]

Nice conspiracy theory style video.

The device shown looks like it somehow triggers the breaker to trip. Perhaps as simple as creating an intentional (current limited???) ground fault if it overheats.

-Jon

Current limited via resistor, hence the GFCI.

Wagos are not the same as what this guy proposed.

It is not a thermal fuse. It is a thermally-activated spring-loaded switch that creates a line-ground fault. Once the fault is created, the up-line breaker is supposed to trip and take out the source supply

Not what the inventor is proposing.

They are like wagos hence why I used that example. Insert wire in and screw down. Push in version could also be designed.

Exactly how they work I have no idea, Id need to look at the patent.

A few that come to mind:

Need hot and ground at every monitored connection so upstream device can be ground-faulted.

As I understand we already need to splice all 3.

Fill requirements with wirenuts would differ from a connector using a spring-loaded thermal switch with extra terminations.

I doubt after refinement they would be much bigger than wagos. Unless you using a pancake box there is plenty of room with the number of wires always being the limiting factor.

Extra connections raise chances of failures.

What extra connections? :blink:

Extra labor & cost.

What extra labor? Cost might be an issue, but it would be a lot cheaper then AFCIs.

Box packing method would have to change because of grouping including hot & ground.

True, it might, but I doubt that would be a disaster or take more time.

Neutral repairs get more complicated as we must include other conductors.

?

Device size increases.

By how much, if at all? Break open a duplex receptacle, there is a lot of empty space inside.

Increase in device complexity and failure modes.

:lol: Obviously you haven't seen Cutler Hammers solution.

Introduces a ground fault that depends on upstream device to clear.

Last I checked all new wiring has an EGC.

Clearing device and path would require higher standard of verification due to introduction of a ground fault.

You mean installing electricians would require higher standards of instantiation Last I checked an open EGC is a danger and a code violation.

Perhaps a better connector is a better solution than monitoring weak connectors.

Perhaps, but then I could argue some of the above concerns to.

It would for what he proposed

I would prefer a better connection and then you could forgo the thermal sensor. Would not have to be thermite but perhaps more idiot-proof. Yes, we are dumbing down our industry because, at least for some of the cases, the idiots don't know how to make a proper connection. Another culprit is cheap devices.

But look at like this, a thermal sensor takes into account all contingencies where as a better connector will not.

Glad you noticed how much bigger it is. Did you also notice the requirement that all of the wires be at the connector (so it can create a ground fault)? No more simple stand-alone neutral splices.

Well of course, its a prototype. I guess you have never seen what your desk top computer or tablet looked like in its developing stages:


https://www.google.com/search?q=eni...p7tz6LixgIVlxOSCh2rEA_n#imgrc=HVRmUhC7IBNKrM:

 

[mbrooke]

One thing that I have always uderstood is to never intentionally overload a circuit with the expectation that a breaker will trip. This often happens with a holiday celebration when too many crockpots are plugged in with the expectation that, don't worry as the breaker we I'll trip on overload. And to never intentionally short circuit with the expectation that as breaker will trip.
The key word is intentional as now you are expecting a breaker to respond which it. I' m not saying that a breaker is unreliable because they are. But when a device downstream internationally causes a short circuit to for a breaker to trip that concerns me.

Its not an intentional short circuit. Its through a current limiting resistor, enough to trip a GFCI. Concept works fine for 3 light GFCI testers as they seem to be legal to sell.

 

[iwire]

Its not an intentional short circuit. Its through a current limiting resistor, enough to trip a GFCI. Concept works fine for 3 light GFCI testers as they seem to be legal to sell.

So its not a simple device, it relies on the functioning of other electronics.

Sorry I don't see that being any better than an AFCI.

 

[mbrooke]

I am against them as well, seeing how they operate.

As it appears, the devices short all conductors together when the temperature reaches a certain level. Then, the OCPD is supposed to trip, removing energy from the circuit.

What if the device fuses and the breaker doesn't trip?

The breaker being used in the video is a GFCI, only a small current is introduced.

 

[mbrooke]

So its not a simple device, it relies on the functioning of other electronics.

Sorry I don't see that being any better than an AFCI.

:happyno: Does this contain electronics?:

https://www.google.com/search?q=ele...residual+current+device&imgrc=_rMMXnRf6TpuiM:


In any case, code already requires GFCIs in most locations in a dwelling, so this device can just piggy back off of them.

 

[user 100]

That's just another useless gimmick to protect the unqualified.

Yep. And another layer of unnecessary complexity. Fact is there is nothing wrong with our current splicing methods that meet 110.14. Take the 2 most common connectors used for our residential wiring during the last half century, the wire nut and those buchanan crimps I referenced earlier in the thread. Despite how many crispy, melted examples we have removed they ARE safe when installed correctly and most operate uneventfully ,safely carrying current until removed. It is never the connectors fault that a connection failed- the blame always rests on the installer. There is no reasonable excuse for a bad connection.

 

[mbrooke]

Yep. And another layer of unnecessary complexity. Fact is there is nothing wrong with our current splicing methods that meet 110.14. Take the 2 most common connectors used for our residential wiring during the last half century, the wire nut and those buchanan crimps I referenced earlier in the thread. Despite how many crispy, melted examples we have removed they ARE safe when installed correctly and most operate uneventfully ,safely carrying current until removed. It is never the connectors fault that a connection failed- the blame always rests on the installer. There is no reasonable excuse for a bad connection.

But our installation methods need to change. No need to pre-twist needs to be be removed from the instructions. In truth unless you make the connection up with your tools and visually have conformation of your splice a wire nut guarantees nothing. It is possible to push one of the conductors down further with the skirt hiding it, making poor contact that can lead to a glowing connection down the road. Also possible is having the spring act as a conductor, something its not.


Back stabbed outlets are another gripe. Those need to be outlawed. The failure rate is astronomical compared to side wired and back clamped varieties. The failures are driving up fire statistics.