arc fault/dual function breaker tripping.

[billydrowne]

I replaced a few two prong plugs, to three prong. put in two dual function breakers, one worked perfectly fine, and the other would trip whenever there was any kind of load introduced to the circuit. I wound up unplugging everything and unscrewing all the light bulbs on that circuit and the breaker would hold, if I reset a gfi, plugged in the fridge (or anything else) it would trip. I searched for Knicks, bad splices, found issues that I thought would cause this and fixed them with the same result. anyone got anything or ever run to something like this? this house was super old, was told it was built in 1910 and has some very old wiring, and new wiring.

 

[hillbilly1]

Neutral from that circuit tied to the neutral of another circuit somewhere. Take the neutral loose at the panel, check continuity to ground. If you have any continuity, with power off, start removing other neutrals in the panel until the continuity goes away, that will probably be the offending circuit. The other possibility, is that circuits neutral may be grounded somewhere.

 

[Little Bill]

Sounds like you either have neutrals crossed somewhere or ground and neutral touching somewhere.

 

[billydrowne]

Neutral from that circuit tied to the neutral of another circuit somewhere. Take the neutral loose at the panel, check continuity to ground. If you have any continuity, with power off, start removing other neutrals in the panel until the continuity goes away, that will probably be the offending circuit. The other possibility, is that circuits neutral may be grounded somewhere.

that's a really good idea thank you!

 

[kwired]

Does dual function or GFCI only breakers have neutral fault detection like most GFCI receptacles have? If so this should trip immediately after reset if there is neutral to ground or to another neutral problem. But if it doesn't have this kind of detection then yes once you put load on it it is going to trip.

 

[synchro]

Does dual function or GFCI only breakers have neutral fault detection like most GFCI receptacles have? If so this should trip immediately after reset if there is neutral to ground or to another neutral problem. But if it doesn't have this kind of detection then yes once you put load on it it is going to trip.

UL 943 applies to all Class-A GFCIs and that would include breakers. So as you say if there's a neutral to ground low resistance fault it should trip without a load. The highest resistance combination of series neutral resistance RN and shunt ground fault resistance RG for the UL N-G fault test is RN = 0.4Ω and RG = 1.6Ω for a 20A device. Because it isn't required to trip for RG greater than 1.6Ω it's hard to tell what trip threshold they actually use in a device without measuring it.

Just for example, say that RN = 0.1Ω and RG =10Ω and assume this doesn't trip the neutral-to-ground detection of the GFCI.
We can calculate the load current that it would take to have 6mA through RG and trip the breaker by recognizing that these two resistors form a current divider: Iload = 6mA x (RN + RG)/RN = 6mA x (0.1 + 10)/0.1 = 0.606A ≅ 0.6A. So any load drawing a current at least this current would trip the breaker with the 10Ω fault resistance.

 

[romex jockey]

UL 943 applies to all Class-A GFCIs

Ul 1699 should but does not

~RJ~

 

[hillbilly1]

Does dual function or GFCI only breakers have neutral fault detection like most GFCI receptacles have? If so this should trip immediately after reset if there is neutral to ground or to another neutral problem. But if it doesn't have this kind of detection then yes once you put load on it it is going to trip.

Come to think of it, I believe they do. I know the receptacles will. Couldn't remember if I had that issue with the arc faults. If thats the case, then I would say somewhere the neutral is also being used as a ground. Probably new wiring with a ground extending the old two wire. Since it trips if something is plugged in, and the test button is working on the gfi receptacle, they are picking up a ground somewhere. Another test to try, is with everything unplugged, check continuity to ground with that circuit neutral disconnected, if open, plug the refrigerator in, and check again.

 

[Edval69]

I recently worked on a project with 262 apartments and we experienced a lot of similar issues. Sounds like possibly a bad breaker, something as simple as a staple pinching your wire or a neutral from another branch circuit spliced wrong. These breakers are very sensitive and bad appliances have been a problem as well.

 

[romex jockey]

Does dual function or GFCI only breakers have neutral fault detection like most GFCI receptacles have?

the only 'function' any enhanced ocpd anywhere on this rock has is parallel detection Kwired.
gfci,gfpe,afci,rcd,cafci, ect.....
~RJ~

 

[kwired]

the only 'function' any enhanced ocpd anywhere on this rock has is parallel detection Kwired.
gfci,gfpe,afci,rcd,cafci, ect.....
~RJ~

For all of those to detect a neutral to ground fault there has to be current flow. GFCI receptacles AFAIK all have neutral-ground detection feature that injects a signal that will make the loop through the neutral/ground bond at the source should there be a neutral/ground fault with no other load current and trips the GFCI. I kind of presume GFCI breakers (and Dual function breakers) also have this feature. AFCI only breaker may not have this feature and would not trip on a neutral /ground fault, until there is current flowing that exceeds any GFPE protection that the unit has.

 

[ramsy]

I replaced a few two prong plugs, to three prong. put in two dual function breakers.. this house was..built in 1910

The NEC historically avoids Class-A GFCI on lighting circuits. It nuisance trips on magnetic ballasts, high-efficiency (HE) luminaries & electronic controls.

Not until 2017 could NFPA-70 pass any requirements for Class-A GFCI protected lighting outlets in 210.8(E) for crawl spaces.

Class-A GFCI breakers for Historic-building plugs shared with lighting, is asking for trouble where ballasts may exist, or HE luminaries, or electronic-lighting controls may be added.

 

[kwired]

The NEC historically avoids Class-A GFCI on lighting circuits. It nuisance trips on magnetic ballasts, high-efficiency (HE) luminaries & electronic controls.

Not until 2017 could NFPA-70 pass any requirements for Class-A GFCI protected lighting outlets in 210.8(E) for crawl spaces.

Class-A GFCI breakers for Historic-building plugs shared with lighting, is asking for trouble where ballasts may exist, or HE luminaries, or electronic-lighting controls may be added.

Is (or has been) somewhat a non issue though. Not many cases would a lighting outlet have fallen into the general GFCI requirements. Throw in a light that is allowed to be cord and plug connected and the possiblity did increase some, but many of those were not even required. One somewhat more common place that would have been required in the past 10-15 years however would be those cheap "plug in shop lights" installed in an area where 210.8 would have called for GFCI protection. A high bay luminaire or similar that is cord and plug connected generally would not be installed in a location where GFCI would be required though possibly may still be required if in a garage or service bay or an indoor wet location, though I seen many indoor wet locations that are not wet at the level the luminaires are installed.

 

[ramsy]

..One somewhat more common place that would have been required in the past 10-15 years however would be those cheap "plug in shop lights" installed in an area where 210.8 would have called for GFCI protection..

No GFCI required w/switched keyless on wall

 

[ptonsparky]

No GFCI required w/switched keyless on wall
View attachment 2552549

Depends...may be required, just not installed.

 

[kwired]

No GFCI required w/switched keyless on wall
View attachment 2552549

First doesn't "keyless" mean it has no switch?

Second, if you use one with an integral receptacle like the one you pictured, and is in a location covered by 210.8, GFCI protection of that receptacle is required. A true keyless wouldn't have a receptacle nor would it need GFCI protection as a result of anything in 210.8, besides the crawlspace lighting that was added in 2017.

 

[ramsy]

..A true keyless wouldn't have a receptacle nor would it need GFCI protection as a result of anything in 210.8..

Ok, for tough inspectors use this adapter with 2-prong shop lights strung end-to-end.

 

[romex jockey]

For all of those to detect a neutral to ground fault there has to be current flow. GFCI receptacles AFAIK all have neutral-ground detection feature that injects a signal that will make the loop through the neutral/ground bond at the source should there be a neutral/ground fault with no other load current and trips the GFCI. I kind of presume GFCI breakers (and Dual function breakers) also have this feature. AFCI only breaker may not have this feature and would not trip on a neutral /ground fault, until there is current flowing that exceeds any GFPE protection that the unit has.

The chief component common to all is the time honored toroidal coil Kwired, no matter what 'electronica' they've lumped on, or 'scada' they lay claim to, it only can sense what a toroid can sense.

So this, you see, is the reality 'gap' every repetitive 'why is my afci trippin' thread after the next on this gawd forsaken device needs to realize diagnostics juxtaposed to manufactures claims

~RJ~

 

[kwired]

The chief component common to all is the time honored toroidal coil Kwired, no matter what 'electronica' they've lumped on, or 'scada' they lay claim to, it only can sense what a toroid can sense.

So this, you see, is the reality 'gap' every repetitive 'why is my afci trippin' thread after the next on this gawd forsaken device needs to realize diagnostics juxtaposed to manufactures claims

~RJ~

The neutral - ground fault detection feature I mentioned does not need "load current" to make it trip. It is injecting a voltage other than the main supply voltage. This same feature would also cause a trip should the ungrounded conductor fault to another ungrounded conductor of same potential (same supply phase) even though there is no load current on either conductor. It would trip if another phase or even grounded conductor was involved, but in those instances there is high fault current and the magnetic trip feature (on circuit breaker types) is opening the circuit anyway should the GFCI features not respond.

 

[romex jockey]

The neutral - ground fault detection feature I mentioned does not need "load current" to make it trip. It is injecting a voltage other than the main supply voltage. This same feature would also cause a trip should the ungrounded conductor fault to another ungrounded conductor of same potential (same supply phase) even though there is no load current on either conductor. It would trip if another phase or even grounded conductor was involved, but in those instances there is high fault current and the magnetic trip feature (on circuit breaker types) is opening the circuit anyway should the GFCI features not respond.

Sorry, but this 'signal' sounds like more manufacturers propaganda Kwired

~RJ~