New home not properly grounded.

[ptonsparky]

My only guess was because our main ground was missing. All the other connections in our main panel were torqued with no loose connections.

That's the problem, it's a guess.
You need more than what you have to back it up.

The double oven doesn't reference the EG for operation. None of your equipment or appliances do.

 

[retirede]

Can anyone explain why my double oven may have caused our garage gfci to trip, afci circuit above it to trip, cause damage to our refrigerator that sits right next to it?

My only guess was because our main ground was missing. All the other connections in our main panel were torqued with no loose connections.

Correlation does not equal causation.

 

[kwired]

What am I looking at on the bottom right in respects to those breaker's, AFCI's ?

White reset button is AFCI, purple reset button is dual function, yellow reset is GFCI. QO or Homeline doesn't matter that is one way to identify which function they are.

 

[kwired]

Re-looking at it The top of the panel has all (most) of the AFCI's
The Single "white tab" breakers also look like their AFCI's

Two wires under 15 AMP breakers?

I can only zoom in once and still can't see it clearly.

Load side neutral terminal is kind of under the ungrounded load terminal of Square D AFCI/GFCI's when looking straight on at an installed breaker. I don't see any "double connections" to any individual terminals, though a standard (non AFCI/non GFCI) breaker 30 amp and less has pressure plate type terminals that accept two (same sized) conductors as standard in both QO and Homeline. AFCI/GFCI however have the pressure plate but the breaker case is designed that it blocks access to one side of the terminal therefore they are only intended to accept a single conductor in the terminal.

 

[kwired]

Only thing I can think of as to why there wasn't an EGC ran to the inside panel is the outside disconnect is labeled "emergency disconnect". The ED is required if they on the 2020 or later. I think there is an exception that allows it to not be the service disconnect.

The bare #6 should be landed on the neutral bar in the disconnect, or removed. The ground, or lack of, would have no effect on the GFCI tripping. There is some other problem, either with the appliance or the GFCI.

May need further clarification in wording but I doubt the intent here is to allow that outside "emergency disconnect" to have additional branch circuits supplied from it. The one in OP doesn't have any installed but has free breaker spaces which could allow such branches to be added someday.

 

[kwired]

Did adding the missing EGC to the subpanel stop the AFCI/GFCI trip issues? Seems kind of unlikely other than there being a weak fault return path that allowed some kind of RF interference to be created or something of that nature.

I once connected an occupancy sensor to bathroom light in my shop (T8 fluorescent). Whenever it turned light on the GFCI receptacle on other side of wall would trip immediately. Light was not connected to load side of this GFCI, can't remember right now if they are on same circuit though, very possibly are.

I removed it and went back to regular single pole switch.

 

[Phelpstx]

So far adding the EGC to the sub panel has stopped the tripping issues of the afci breakers and the gfci tripping in the garage. We have not been using our oven and don’t plan on it until it’s replaced.

I am in belief that because the oven did not have a ground that may have led to some fault within the oven which may caused some type of back-feed to cause some imbalanced load that caused the afci to trip, and gfci to trip in our garage or like you said some type of interference caused it to trip.

Regardless it did some serious damage when we had that lower oven on because it burned up two surge protectors and damaged our water dispenser or maybe we had a surge and without a main ground it made our equipment more vulnerable which could have impacted the oven to cause some kind of fault.

 

[GeorgeB]

Good point! So the 25 ohms would not apply since I have a single rod and U/f ground?

If your "U/f" is Ufer (CEE, concrete encased electrode) in a slab on grade without vapor barrier, that alone meets the requirement. You're not required to have the rod.

 

[kwired]

So far adding the EGC to the sub panel has stopped the tripping issues of the afci breakers and the gfci tripping in the garage. We have not been using our oven and don’t plan on it until it’s replaced.

I am in belief that because the oven did not have a ground that may have led to some fault within the oven which may caused some type of back-feed to cause some imbalanced load that caused the afci to trip, and gfci to trip in our garage or like you said some type of interference caused it to trip.

Regardless it did some serious damage when we had that lower oven on because it burned up two surge protectors and damaged our water dispenser or maybe we had a surge and without a main ground it made our equipment more vulnerable which could have impacted the oven to cause some kind of fault.

If the oven was the trigger and you stopped using it, I'd assume you really don't know if adding that EGC stopped the tripping then.

If there is a ground fault in the oven it very well might trip the breaker feeding the oven now should you turn it on where before it had no low resistance return path to develop enough current to trip it.

 

[Phelpstx]

If the oven was the trigger and you stopped using it, I'd assume you really don't know if adding that EGC stopped the tripping then.

If there is a ground fault in the oven it very well might trip the breaker feeding the oven now should you turn it on where before it had no low resistance return path to develop enough current to trip it.

Would it make sense if you didn’t develop enough current to trip the oven breaker, that the ground current could have been floating and trip out a gfci nearby? The gfci that kept tripping when we used our oven is located right next to the main panel.

 

[Little Bill]

Would it make sense if you didn’t develop enough current to trip the oven breaker, that the ground current could have been floating and trip out a gfci nearby? The gfci that kept tripping when we used our oven is located right next to the main panel.

It wouldn't make any sense. A GFCI doesn't trip that way. It measures any difference in current between the hot and neutral. If the current through it takes a secondary path (ground fault) the neutral current would be lees than the hot current. It only takes 4-6 mA of imbalanced current to trip a GFCI.
Was the GFCI a breaker or receptacle?

 

[kwired]

Would it make sense if you didn’t develop enough current to trip the oven breaker, that the ground current could have been floating and trip out a gfci nearby? The gfci that kept tripping when we used our oven is located right next to the main panel.

Only way it trips the GFCI on another circuit is if somehow the load side of that GFCI protected circuit is interconnected with it. Or as we already mentioned some kind of RF or other signal being imposed on the supply side that the GFCI logic circuit doesn't play well with. Otherwise by design the GFCI will only trip on unbalanced current being imposed on it's sense coil. Should there be inadvertent interconnected neutral somewhere this is a possibility, maybe even with the AFCI that is tripping as well.

ETA: even a "bootleg" neutral is possible, say the oven needed a neutral but original circuit did not contain one so they grabbed a neutral elsewhere and it happened to be the GFCI protected portion of another circuit - that definitely would trip it.

 

[Phelpstx]

It wouldn't make any sense. A GFCI doesn't trip that way. It measures any difference in current between the hot and neutral. If the current through it takes a secondary path (ground fault) the neutral current would be lees than the hot current. It only takes 4-6 mA of imbalanced current to trip a GFCI.
Was the GFCI a breaker or receptacle?

It was a GFCI receptacle.

 

[tortuga]

Did we confirm it was a PVC nipple between the service disconnect and the loadcenter?

If so a that would be all EGC's and metal frames tied together but not to neutral.
A huge amount of copper and metal all tied together floating via capacitive coupling and possibly a high resistance earth connection would be a very messy situation.
Whatever 'earth leakage' all the various electronic circuits created would probably circulate and create voltage swings on the EGC.
A Metal Oxide Varistor (MOV) is a voltage dependent variable resistor and they are included in most electronic power supplies and tied to the EGC. If the EGC was floating and could swing with AC then I wonder if these could all start feeding each other a current loop.

 

[Phelpstx]

They used PVC from the service disconnect to our main lug panel. The only bare coppers we had in our main lug panel was a #6 bare copper run to a low voltage termination block, and a #6 bare copper gas line bond. I confirmed today that our gas line is plastic from the meter to the street.

 

[Phelpstx]

Our oven wire is 6/3 with ground. Dedicated 40 amp circuit.

Met with the builder today and they agreed to replace the oven. Our panel is now grounded and we’re not having issues with any of our electric in our home.

As a precaution I was just going to manually test each of our AFCI and GFCI breakers.

Since our home was not grounded for almost a year is there any additional testing I should have them do? They were planning on just checking the outlets to see how they are wired. Do a visual assessment in the attic. They have already checked all the connections at the meter, disconnect, and load center.

 

[farmantenna]

after reading all this I'll say this: If electrical systems or circuits or whatever are not properly grounded crazy unexplained things start happening. I've seen it many times when unqualified people start doing electrical work. " People are shocked while grabbing this while touching that when it's wet". "people are getting shocked when they touch the front entry door (aluminum)" These incidents I unfortunately got called about and was lack of grounding. Who knows what's going to happen when your main panel has no equipment ground but has wires going to gas pipes and tel/tv demarcation point.

 

[electrofelon]

after reading all this I'll say this: If electrical systems or circuits or whatever are not properly grounded crazy unexplained things start happening. I've seen it many times when unqualified people start doing electrical work. " People are shocked while grabbing this while touching that when it's wet". "people are getting shocked when they touch the front entry door (aluminum)" These incidents I unfortunately got called about and was lack of grounding. Who knows what's going to happen when your main panel has no equipment ground but has wires going to gas pipes and tel/tv demarcation point.

I disagree, nothing crazy or weird happens. A system can be completely ungrounded and floating (although that would be nearly impossible to achieve) and everything will work just fine. Equipment earthing doesn't do much and won't reduce shocks. Equipment bonding back to the source of course adds some safety by deactivating the circuit if there is a fault.

 

[letgomywago]

I disagree, nothing crazy or weird happens. A system can be completely ungrounded and floating (although that would be nearly impossible to achieve) and everything will work just fine. Equipment earthing doesn't do much and won't reduce shocks. Equipment bonding back to the source of course adds some safety by deactivating the circuit if there is a fault.

So many old houses had wood everything and no grounds. The danger came from the metal piping and water with electrolytes

 

[Phelpstx]

We have not had any issues since we stopped using the original oven that came with the house and got it replaced. It’s possible that since the original oven was never properly grounded that it got damaged from a surge. If you don’t have a properly grounded electrical system all of your equipment is going to be more vulnerable to damage from a surge.

They did insulation resistance testing with a Megger for the oven wire and it tested good. So far after we got our system grounded properly and the oven replaced we haven’t had any issues.

I’ve had experience with a home not being properly grounded that got hit with a surge from lightning that caused the home later to catch on fire.