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Black Angus McPherson

Question for the Electricians among us

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First, the guy that built this house did a lot of weird stuff.  Electrical wiring included.  We started having a problem with the GFI's in our two bathrooms.

 

The GFI in bathroom A works fine, but the GFI in bathroom B doesn't work.  If the GFI's don't work then the outside outlets, front and back, along with the garage outlets don't work.  I thought GFI B was broken so I replaced it.  Same problem.  Reset GFI B and GFI A cuts out.  Reset GFI A and GFI B cuts out.  And if GFI A is out there is no power to GFI B.  No effect on the breaker in the basement.

 

Nothing plugged in in any of the associated outlets.  My guess is there is some type of short between GFI B and one of the other outlets.  IF that is the case how does one check the circuit between GFI B and the various outlets without power?

 

We should have a licensed Electrician out to check on this sometime next week, but I thought it would be nice (and save some time) if I could give him some idea where to start checking.  Plus, I'd really like to know for myself.

 

So, can you tell what the problem is from my description?  If so, what's the solution?

 

Thanks,

 

Angus

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Don't use those circuits till fixed.

Who did the wiring?

Sounds like your common and GND are making contact.

OLG 

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Bathroom GFCI's should not leave a bathroom type circuit per Code (depends on how old the house is).

 

When they daisy chain outlets to one GFCI, if they put the wires in the wrong place it will not work. It's not just white, black, copper. There is an in and an out.

 

Let them figure it out.

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Posted (edited)

Sent you a pm. I might be over your way on Saturday if you have not had it fixed..

Edited by Maddog McCoy SASS #5672

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14 hours ago, The Original Lumpy Gritz said:

 

Who did the wiring?

 

OLG 

 

No idea.  I can only assume it was the electrician contracted for the job when the house was built  ~1984

 

12 hours ago, Marshal Mo Hare, SASS #45984 said:

Is it a new problem?

 

Yep, started a couple days ago.  We've lived here 20 years.

 

Angus

 

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Sounds like a polarity issue with one of the outlets on that circuit.

 

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OP, did you make additions/changes to the circuits before these issues started? 

OLG 

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15 hours ago, Abilene Slim SASS 81783 said:

Let the electrician diagnose it. He’ll be on the scene and we will not. 

What he said ^^^^

 

Any electrician worth their salt will smile and say "Thanks" when you tell him what you think is wrong but he or she  will not trust what you say until they verify it.

It's no reflection on you. It's electricity. 

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1 hour ago, The Original Lumpy Gritz said:

OP, did you make additions/changes to the circuits before these issues started? 

OLG 

 

Nope, not a thing.

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Hang any pictures lately? :D

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1 hour ago, Michigan Slim said:

Hang any pictures lately? :D

This isn’t really a joke. My brother shorted a line drilling a screw into his wall. He missed the stud but hit the line coming from his attic to an outlet below. He didn’t get zapped but his drill driver didn’t fair too well and luckily he didn’t catch the house on fire. :D

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3 minutes ago, Pat Riot, SASS #13748 said:

This isn’t really a joke. My brother shorted a line drilling a screw into his wall. He missed the stud but hit the line coming from his attic to an outlet below. He didn’t get zapped but his drill driver didn’t fair too well and luckily he didn’t catch the house on fire. :D

The screw acted like a fuse?

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Hopefully you did not cross up any wires when you replaced GFCI B.  There is a Line and Load side and the Hot and Neutral wires cannot be crossed on the receptacle. 

 

Another thought, do you have any attic fans? I found a short in the wiring on an attic fan that was tied into the garage/patio receptacle circuit on a house that was built in 1985.

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6 minutes ago, Pat Riot, SASS #13748 said:

This isn’t really a joke. My brother shorted a line drilling a screw into his wall. He missed the stud but hit the line coming from his attic to an outlet below. He didn’t get zapped but his drill driver didn’t fair too well and luckily he didn’t catch the house on fire. :D

Hitting water lines with screws/nails also is a bummer!

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4 minutes ago, Marshal Mo Hare, SASS #45984 said:

The screw acted like a fuse?

Short. 

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23 minutes ago, Marshal Mo Hare, SASS #45984 said:

Did it melt?

Yep, and then some. That’s when he found the breaker was bad and didn’t trip but burnt up. The insulation of the Romex cooked. He had a bit of drywall and electrical work to repair. 
 

I think he ended up replacing his entire breaker panel and he replaced some wire and fixtures. His house was built in 3 stages. The original home was built in the early 60’s then additions were put on in the 70’s. 

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Posted (edited)

Just a thought.....check the white (neutral) wires coming from the bathrooms into the breaker box.  It may be that the white wire from Bathroom A is wired to Bathroom B's GFCI's breaker and the white from Bathroom B is wired to Bathroom A's GFCI breaker.

 

Kajun

Edited by Krazy Kajun
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3 hours ago, Krazy Kajun said:

Just a thought.....check the white (neutral) wires coming from the bathrooms into the breaker box.  It may be that the white wire from Bathroom A is wired to Bathroom B's GFCI's breaker and the white from Bathroom B is wired to Bathroom A's GFCI breaker.

 

Kajun

Kind of hard to do when houses built since WWII use cable that contains the line & neutral conductors & starting some time after 1960 a bare ground conductor.  I haven't researched it; however but I have disassembled a bad GFCI receptacle.  They include a zero sequence current transformer; which is a current transformer that all current carrying conductors pass through.  The magnetic fields from each conductor cancel out if there isn't current leakage to ground on load side of the GFCI.  These CT's have a lot of secondary winding turns so that the electronics sense less than a few milliamps of ground fault current.  I suspect they also sense the common mode voltage, voltage difference between neutral & ground.  The neutral is also called the "grounded circuit conductor"; because, the neutral is bonded to ground at the service entrance disconnect (main ckt. bkr. or fuse switch) where the box is also bonded to a ground rod or metal cold water pipe or rebar or reinforcing mesh in the slab.

Note: a GFCI receptacle can be used to replace a receptacle that doesn't have a ground pin socket.  In fact unless you replace like for like you have to use a GFCI receptacle to replace one of these old receptacles.  You don't have to run a bare or green insulated wire from the service panel metal enclosure to the GFCI receptacle.  All you have to do is attach a label stating the circuit isn't grounded.  Stick on labels are include with the packaging.

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Posted (edited)
10 hours ago, J.D. Daily said:

Kind of hard to do when houses built since WWII use cable that contains the line & neutral conductors & starting some time after 1960 a bare ground conductor.  I haven't researched it; however but I have disassembled a bad GFCI receptacle.  They include a zero sequence current transformer; which is a current transformer that all current carrying conductors pass through.  The magnetic fields from each conductor cancel out if there isn't current leakage to ground on load side of the GFCI.  These CT's have a lot of secondary winding turns so that the electronics sense less than a few milliamps of ground fault current.  I suspect they also sense the common mode voltage, voltage difference between neutral & ground.  The neutral is also called the "grounded circuit conductor"; because, the neutral is bonded to ground at the service entrance disconnect (main ckt. bkr. or fuse switch) where the box is also bonded to a ground rod or metal cold water pipe or rebar or reinforcing mesh in the slab.

Note: a GFCI receptacle can be used to replace a receptacle that doesn't have a ground pin socket.  In fact unless you replace like for like you have to use a GFCI receptacle to replace one of these old receptacles.  You don't have to run a bare or green insulated wire from the service panel metal enclosure to the GFCI receptacle.  All you have to do is attach a label stating the circuit isn't grounded.  Stick on labels are include with the packaging.

 

JD Daily, all true.  I was just trying to provide something to check that would cause the scenario the OP had posted in the first post on this thread. 

 

The CT is there to sense any differences in neutral and ground currents.  I don't think there is voltage sensing as there would have to have a PT set up for that.  I think the voltage produced from the secondary of the CT is tied to the tripping sequence for the small breaker inside the receptacle or in the breaker.

 

Kajun

 

Edited by Krazy Kajun

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The house was built in 1984. It was common to use one circuit for the garage, bathroom(s) and exterior receptacles with a GFI receptacle at the "head" of the circuit. Most likely, this would be the closest one to the main electrical panel. I have to guess that this is the case in this instance. I would have to also guess that the reason that there is a GFI receptacle in each bathroom is that the previous owner had nuisance tripping and make it easier to reset rather than go to the other bathroom to reset. As bathroom appliances started to draw more amperage, National Electric Code required that bathroom receptacles be on their own 20 amp circuit with GFI protection. I think that this house was built before that code change. Normally there isn't a problem with two GFI devices on the same circuit. I have replaced bad GFI receptacles and breakers. There is a chance that Angus got the line and/or load mixed up on the replacement receptacle. There is also a chance that the ground (or something grounded) is in contact with the neutral at the receptacle or elsewhere.

 

In the original post, it was stated that nothing else was plugged into the circuit. Does that imply that there is nothing plugged in the garage or exterior receptacles? That would be a rarity as there is usually something like a water softener, cordless tool charger, low volt landscaping light transformer, etc plugged in somewhere at those locations. Was there a heavy rain storm or possible sprinklers spraying on the exterior receptacles?

 

I sounds as if there was one problem that has now become two problems.

 

IMO, this is a job that is better left to a professional. This is the reason that I was hesitant to post on this thread......electrical malfunctions can and, at times will, cause fire and shock hazards.

 

Good luck and I hope the remedy is quick and easy on the wallet.

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On 7/7/2020 at 10:17 PM, Blast Masterson said:

 

 

When they daisy chain outlets to one GFCI, if they put the wires in the wrong place it will not work. It's not just white, black, copper. There is an in and an out.

 

Let them figure it out.

 

What he said.  I had an outdoor GFCI that went bad.  Connected to it were the patio lights and other outlets on the deck.  Replaced it but had the "in" wires in the "out" part of the receptacle.  Once I switched them around all was good.  Later, I disassembled the bad receptacle to learn something.  What I learned is that about a dozen tiny ants can short out a receptacle for good.  They were cooked.  Had a few wood shavings in the receptacle and the box.

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After 20 years with zero problems I had a master bath room GFI trip.  Reset might last a few weeks or instantly trip again.  Simple fix I thought, bad GFI so I replaced it.  Lasted a week before the new GFI started acting like the old GFI.  Started tracing and disconnecting everything I found on that circuit.  Circuit ended at an outside receipt.  I took the cover off the outside receipt and found the black screw terminal was about a 1/8" from the metal box with corrosion.  Appears bugs would periodically bridge between the two causing the GFI to trip.  I wrapped the receipt with electrical tape and centered in the metal box.  Going on a few years and the GFI hasn't tripped again.

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Won't GFCIs fail like this if you have more than one on a circuit?

 

Do the GFCI circuits go into the kitchen?  Appliances like microwaves or refrigerators can randomly mess up a GFCI circuit.  When I say mess up, I'm talking the charred kind of messed up.  

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Posted (edited)

Not surprisingly you guys have passed way above my knowledge of electrical wiring.

 

A couple of your new questions that I understand and can answer:

 

I went around and checked all outlets outside and in the garage unplugging everything.

 

I didn't know anything about "in" and "out" or "line" and "load" sides on GFI circuits.  I used the old GFI as a reference when changing wires onto the new GFI.  I suppose I could have gotten them mixed up.  Also the new GIF is slightly different than the one it replaced.  It has a small light in it.

 

I do have an attic fan.  I haven't checked that.  Haven't used it for at least a couple months.

 

Haven't hung any pictures.  :D

 

I don't know what "PT" or "CT" means.

 

Several heavy rains in the past few weeks.  Not likely rain got into outside outlets, but not impossible.

 

19 hours ago, Krazy Kajun said:

Just a thought.....check the white (neutral) wires coming from the bathrooms into the breaker box.  It may be that the white wire from Bathroom A is wired to Bathroom B's GFCI's breaker and the white from Bathroom B is wired to Bathroom A's GFCI breaker.

 

Kajun

 

I don't know how I would even do this.  The wires run thru the walls, so how would I know which white wire went where?

 

Not affecting anything in the kitchen.  The only outlets affected are the GFI in bathroom B, the garage outlets and the outside outlets.

 

All the above is why I'll be paying a licensed electrician the big bucks to fix the problem.

 

BTW, this is interesting.  Maybe I should have been an electrician.

 

Angus who knows the difference between to, two and too, they're, there and their, then and than, but still has problems with affect and effect.

(sensing a tangent coming on)

 

 

Edited by Black Angus McPherson

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No, multiple GFI receptacles on the same circuit is not normally a problem.

 

GFI protection is required by present day NEC for kitchen counter receptacles and receptacles within 6' of any sink in the kitchen. Having a refrigerator on a GFI protected circuit is not recommended. If the GFI trips for any reason and is not attended to, you'll lose whatever is in the fridge. I've not seen problems with a microwave (that is not faulty) plugged into a kitchen counter receptacle having any affect on a GFI receptacle. The microwave's use in conjunction with another counter top type appliance is another story though, especially if they over amp the circuit for any length of time.

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4 hours ago, Krazy Kajun said:

 

JD Daily, all true.  I was just trying to provide something to check that would cause the scenario the OP had posted in the first post on this thread. 

 

The CT is there to sense any differences in neutral and ground currents.  I don't think there is voltage sensing as there would have to have a PT set up for that.  I think the voltage produced from the secondary of the CT is tied to the tripping sequence for the small breaker inside the receptacle or in the breaker.

 

Kajun

 

 

1 minute ago, Black Angus McPherson said:

Not surprisingly you guys have passed way above my knowledge of electrical wiring.

 

A couple of your new questions that I understand and can answer:

 

I went around and checked all outlets outside and in the garage unplugging everything.

 

I didn't know anything about "in" and "out" or "line" and "load" sides on GFI circuits.  I used the old GFI as a reference when changing wires onto the new GFI.  I suppose I could have gotten them mixed up.  Also the new GIF is slightly different than the one it replaced.  It has a small light in it.

 

I do have an attic fan.  I haven't checked that.  Haven't used it for at least a couple months.

 

Haven't hung any pictures.  :D

 

I don't know what "PT" or "CT" means.

 

Several heavy rains in the past few weeks.  Not likely rain got into outside outlets, but not impossible.

 

 

I don't know how I would even do this.  The wires run thru the walls, so how would I know which white wire went where?

 

Not affecting anything in the kitchen.  The only outlets affected are the GFI in bathroom B, the garage outlets and the outside outlets.

 

BTW, this is interesting.  Maybe I should have been an electrician.

 

Angus who knows the difference between to, two and too, they're, there and their, then and than, but still has problems with affect and effect.

(sensing a tangent coming on)

 

 

PT is the acronym of Potential Transformer.  A PT is used to isolate the AC voltage source from a voltage measuring circuit & also to reduce the measured voltage to less than the maximum allowable voltage of the sensing circuit.  The same voltage reduction can be done with a voltage divider without isolation.  CT is the acronym for Current Transformer.  It does the same thing as a PT however the output of the secondary winding is current not voltage.  PT's and CT's are used in AC power monitoring & protection applications.

P.S.  Every homeowner should have a 120V circuit tester.  The are available at just about every hardware or home improvement store.  It has a pulg & 3 three lights.  When plugged into a 15A or 20A 120V receptacle the lights may or may not be on.  The text on the tester states the condition of the circuit based on light pattern.  Every electrician has one in their tool box.  They will also have a circuit tracer to determine where an open circuit fault is located.

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18 minutes ago, J.D. Daily said:

 

 

P.S.  Every homeowner should have a 120V circuit tester.  The are available at just about every hardware or home improvement store.  It has a pulg & 3 three lights.  When plugged into a 15A or 20A 120V receptacle the lights may or may not be on.  The text on the tester states the condition of the circuit based on light pattern.  Every electrician has one in their tool box.  They will also have a circuit tracer to determine where an open circuit fault is located.

 

+1

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On 7/9/2020 at 3:08 PM, Cypress Sun said:

I've not seen problems with a microwave (that is not faulty) plugged into a kitchen counter receptacle having any affect on a GFI receptacle. The microwave's use in conjunction with another counter top type appliance is another story though, especially if they over amp the circuit for any length of time.

 

I have.  There was a loud pop and then suddenly black stripes appeared on the sheetrock.  The electrician who came out to replace the wiring told us all about it and said that was why circuits intended for microwaves or fridges should never be gfci circuits.  In our case it was a second microwave and we just grabbed the closest outlet.  He said it was the motor kicking on and off slowly wearing it out, then one day (probably 5 years of heavy use later) the current rush hits just right and you have a short.  I found a different outlet for that microwave after this incident. 

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24 minutes ago, Ramblin Gambler said:

 

He said it was the motor kicking on and off slowly wearing it out, then one day (probably 5 years of heavy use later) the current rush hits just right and you have a short.  I found a different outlet for that microwave after this incident. 

The only motor(s) in a microwave oven would be at most less than 1/10 Hp for a turn table & cooling air fan for the magnetron tube.  The magnetron draws al lot of power.

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