AFCI and GFCI Kitchens

[kwired]

And if we are replacing a 2 wire receptacle we have to use afci and gfci.

Maybe maybe not.
There is another thread that questions this about replacements and seems to point out some inconsistencies between a couple code sections - without looking I recall a portion of 210.12 not requiring it but a portion of 406 requiring adding AFCI when changing out an existing receptacle. I can't think of a requirement for GFCI protection - if one were to replace with a 2 wire receptacle - complications come however when one considers the fact you likely will not find a replacement two wire receptacle that also provides AFCI and/or is tamper resistant as that is likely required as well.

Debates about whether or not AFCI belong in the code are another issue but get mixed into the discussion.

 

[romex jockey]

And male Leghorn chickens weigh 4-5 pounds at adulthood but that is not what we are talking about is it?

twice that if you know how to raise 'em....

Explain how the BX we are talking about can heat up without a ground fault.

Don't wonder off into left field, stick with the specific topic you pulled my quote from.

Not a problem, because i live in BX-land .

The vast majority of BX is, at this point in it's existence, poorly if anything of it grounded.

The many wiring methods over time that have made to it, or simply age and the fact that the outer wrap is 5X's the interior conductors provide an R factor conducive to energization w/o OCPD being bothered at all

In fact we've often found the 'dotted line' working it's way through the horsehair plaster and lath a sure sign.

I.E>~ It heats up, glows and DOES NOT go to ground. Conversely , many of the older fixtures and terminations 'glow' because the solder once used has deteriorated , and 'fleur de friction tape' is noteably wafting through the air.

Dealing with it is like trying to sew potato chips together .....

And i haven't even gotten to express what a parallel noodle can do.....but i digress

Because my only insistence was a GC can exist w/o going to ground

It can , despite ANY wiring method

thx for playin'....


~RJ~

 

[GoldDigger]

Dealing with it is like trying to sew potato chips together .....

thx for playin'....


~RJ~

You just need to use a high speed drill to make the holes first. :angel:

 

[George Stolz]

twice that if you know how to raise 'em....





Not a problem, because i live in BX-land .

The vast majority of BX is, at this point in it's existence, poorly if anything of it grounded.

The many wiring methods over time that have made to it, or simply age and the fact that the outer wrap is 5X's the interior conductors provide an R factor conducive to energization w/o OCPD being bothered at all

In fact we've often found the 'dotted line' working it's way through the horsehair plaster and lath a sure sign.

I.E>~ It heats up, glows and DOES NOT go to ground. Conversely , many of the older fixtures and terminations 'glow' because the solder once used has deteriorated , and 'fleur de friction tape' is noteably wafting through the air.

Dealing with it is like trying to sew potato chips together .....

And i haven't even gotten to express what a parallel noodle can do.....but i digress

Because my only insistence was a GC can exist w/o going to ground

It can , despite ANY wiring method

thx for playin'....


~RJ~

I think you're missing the point. There must be a circuit for the heating to occur; the most likely being a ground fault because the neutral/phase conductors are insulated, and the EGC (or bare sheathing not connected to a EGC) are not insulated. Embed a metal sheathing in concrete plaster, and it has a possibility of completing a circuit to earth, which is connected to the source, completing a circuit, regardless of the resistance of the path involved.

It is the difference between "being an effective EGC" and "offering a conductive path to earth."

 

[iwire]

Not a problem, because i live in BX-land .

The vast majority of BX is, at this point in it's existence, poorly if anything of it grounded.

The many wiring methods over time that have made to it, or simply age and the fact that the outer wrap is 5X's the interior conductors provide an R factor conducive to energization w/o OCPD being bothered at all

In fact we've often found the 'dotted line' working it's way through the horsehair plaster and lath a sure sign.

I.E>~ It heats up, glows and DOES NOT go to ground.

What is heating up the BX armor?

What is the circuit flow if not to ground?

 

[mbrooke]

What is heating up the BX armor?

What is the circuit flow if not to ground?

Maybe I didn't explain it right correctly and RJ got confused.


Picture old BX cable. It has no bonding strip, just wraps steel interlocked (woven) one on top another. The impedance of the steel is unknown, probably higher the the equivalent EGC. Further the wraps themselves have impedance so current can not just flow ("jump") from one wrap to the other. Current is basically left to travel in a spiral. Both of the above combined add substantial impedance to the fault current path.

When a short circuit occurs such as a hot touching a metal box with the BX armor connected to it, current is then placed on the high impedance armor back to the panel. Because of the high impedance the breaker may not trip, or not trip fast enough. The armor will then heat up possibly to the point of igniting flammable material in contact with the armor.

A NEMA rep made a claim that AFCIs can help in such a wiring system, however some manufactures have taken 30/50ma GFP out of AFCIs. In such a case there is question whether or not an AFCI without GFP can mitigate this hazard.

 

[ActionDave]

Maybe I didn't explain it right correctly and RJ got confused.


Picture old BX cable. It has no bonding strip, just wraps steel interlocked (woven) one on top another. The impedance of the steel is unknown, probably higher the the equivalent EGC. Further the wraps themselves have impedance so current can not just flow ("jump") from one wrap to the other. Current is basically left to travel in a spiral. Both of the above combined add substantial impedance to the fault current path.

When a short circuit occurs such as a hot touching a metal box with the BX armor connected to it, current is then placed on the high impedance armor back to the panel. Because of the high impedance the breaker may not trip, or not trip fast enough. The armor will then heat up possibly to the point of igniting flammable material in contact with the armor.

A NEMA rep made a claim that AFCIs can help in such a wiring system, however some manufactures have taken 30/50ma GFP out of AFCIs. In such a case there is question whether or not an AFCI without GFP can mitigate this hazard.

You are describing a high impedance fault, but still a ground fault.

 

[mbrooke]

You are describing a high impedance fault, but still a ground fault.

Id say a high impedance EGC. The fault itself may be zero ohms, but the cable armor is well above that.

 

[peter d]

Id say a high impedance EGC. The fault itself may be zero ohms, but the cable armor is well above that.

A GFCI should trip with a wire to armor fault with unbonded BX. The best thing to do with that stuff is rip it out completely. Barring that, GFCI protection is the next best thing.

 

[mbrooke]

A GFCI should trip with a wire to armor fault with unbonded BX. The best thing to do with that stuff is rip it out completely. Barring that, GFCI protection is the next best thing.

Which is why they should not be taking it out of AFCIs. But NEMA seems to say its a none issue.

 

[peter d]

Which is why they should not be taking it out of AFCIs. But NEMA seems to say its a none issue.

Sure inspires a lot of confidence in NEMA. :happyno::happyno:

 

[mbrooke]

Sure inspires a lot of confidence in NEMA. :happyno::happyno:

I wish NEMA as a whole would be more forthcoming.

 

[iwire]

Maybe I didn't explain it right correctly and RJ got confused.

What you describe would be a detectable ground fault long before heating happens.

 

[kwired]

A GFCI should trip with a wire to armor fault with unbonded BX. The best thing to do with that stuff is rip it out completely. Barring that, GFCI protection is the next best thing.

Completely isolated armor will not trip the GFCI. Contact anything with that armor that provides some continuity to ground and you have a current path and GFCI will trip. You need about 20Kohm max in a 120 volt circuit before you get into threshold levels of whether or not the GFCI will trip. Install that cable in dry wood framing and it can sit there energized and never trip the GFCI, until someone comes along and introduces another path with low enough resistance, may just need to touch the metal outlet box to accomplish this task, and that person will still get a shock even though the GFCI did trip - it takes current to trip the GFCI.

 

[mbrooke]

What you describe would be a detectable ground fault long before heating happens.

With a GFP or GFCI breaker.

 

[ableliston]

Respect for both sides.

Respect for both sides.

I have been watching this thread for a while. I have been a master electrician for about 10 years. So I've been in this field for 15 years. I see and understand both sides of this discussion. I am frustrated with the new codes because I think they are driven by big business and deep pockets. However, I think we have someone on this thread that is taking his personal time to help us understand what is coming down the pipe from above. I don't see how you add to or learn from a discussion by being confrontational. Bryan P. Holland (bhpgravity) has insight that ,regardless of our feelings of the codes, can explain the reason and installation requirements to pass inspections. I want to use him as a resource to understand the code. I don't want the only person talking, to quit because he's being accosted by criticism.

 

[kwired]

I have been watching this thread for a while. I have been a master electrician for about 10 years. So I've been in this field for 15 years. I see and understand both sides of this discussion. I am frustrated with the new codes because I think they are driven by big business and deep pockets. However, I think we have someone on this thread that is taking his personal time to help us understand what is coming down the pipe from above. I don't see how you add to or learn from a discussion by being confrontational. Bryan P. Holland (bhpgravity) has insight that ,regardless of our feelings of the codes, can explain the reason and installation requirements to pass inspections. I want to use him as a resource to understand the code. I don't want the only person talking, to quit because he's being accosted by criticism.

The reasons/requirements to pass inspections are fairly black and white in the printed code, what the debates are typically about is whether or not AFCI does do what the manufacturers promised they will do, and whether the methods used to get these devices into code are reasonable or if the manufactures were just pushing to get them in so they can get a return on investment in developing what they do have, even if it is not yet perfected.

The concept of these devices is great, whether or not the products on the market actually meet that concept is what is questionable, then to be forced to use something with such questions gets many fired up about it.

 

[mbrooke]

I have been watching this thread for a while. I have been a master electrician for about 10 years. So I've been in this field for 15 years. I see and understand both sides of this discussion. I am frustrated with the new codes because I think they are driven by big business and deep pockets. However, I think we have someone on this thread that is taking his personal time to help us understand what is coming down the pipe from above. I don't see how you add to or learn from a discussion by being confrontational. Bryan P. Holland (bhpgravity) has insight that ,regardless of our feelings of the codes, can explain the reason and installation requirements to pass inspections. I want to use him as a resource to understand the code. I don't want the only person talking, to quit because he's being accosted by criticism.

We are not trying to be confrontational (and that is not my intent even though being honest I do get a tad outspoken), however there appears to be a disconnect between what AFCI affiliated entities claim vs hard science/evidence.

BphGravity is welcome to post here, and he by all means has an excellent understanding of the code while being an excellent contributor to this forum and I certainly want him to stay here. Nearly all of our disagreements have come solely from AFCIs. While bphgravity is 100% correct about AFCIs from a code standpoint I do not agree with those claims as they apply to theoretical or real world instances.

 

[klineelectric]

The reasons/requirements to pass inspections are fairly black and white in the printed code, what the debates are typically about is whether or not AFCI does do what the manufacturers promised they will do, and whether the methods used to get these devices into code are reasonable or if the manufactures were just pushing to get them in so they can get a return on investment in developing what they do have, even if it is not yet perfected.

The concept of these devices is great, whether or not the products on the market actually meet that concept is what is questionable, then to be forced to use something with such questions gets many fired up about it.

Perfectly stated:thumbsup:

 

[peter d]

We are not trying to be confrontational (and that is not my intent even though being honest I do get a tad outspoken), however there appears to be a disconnect between what AFCI affiliated entities claim vs hard science/evidence.

BphGravity is welcome to post here, and he by all means has an excellent understanding of the code while being an excellent contributor to this forum and I certainly want him to stay here. Nearly all of our disagreements have come solely from AFCIs. While bphgravity is 100% correct about AFCIs from a code standpoint I do not agree with those claims as they apply to theoretical or real world instances.

I agree.

Without these forums and the ability to bring our concerns to the airwaves (so to speak), many of us would still be in the dark about the scam of the AFCI. I still believe the line in the sand is drawn and there is no compromise possible between the manufacturers and other pro-AFCI people. They gave us a scam and we should do everything possible to fight against it.