I have a 20A circuit clearly labeled “outlets” in the panel on the workshop (new home to us).  Everything worked until recently where I noticed two EGO battery chargers not working.  GFCI INSIDE would not reset so I replaced.  Now, it trips immediately which made me consider the OUTSIDE GFCI which I found did not reset.  Have no idea how old the 2 failed GFCI outlets are.  

I’m thinking next step, replace outside GFCI.  Sound right.  

Power is off.

Two GFCIs on the same circuit?

Time to get rid of one.

Are the two GFCI on the same circuit?  There should only be one.  The first outlet past the CB.

If they are tripping, do you have a short somewhere?

GFCI or breaker is tripping?

This.  Maybe go old school with MSpaint.

GFCI  is tripping.  Like I said one is OUTSIDE and one INSIDE.  I’m assuming the OUTSIDE GFCI is first in line from the Panel.

Outside one is low, inside one is chest level, not more than a few feet apart on opposite sides of the wall.

Need more info.   Figure out everything on the circuit, unplug anything on it and try again.  You should NOT have 2 GFCI on the same circuit.

You probably wired the gfci wrong, with the neutral or the load side wired to the line side, or some such. Some brands the line is on the top and load is on the bottom, but others it's the opposite.

So here is the deal: Electrons that flow through a conductor in an AC system alternate back & forth at a rate that is based on the frequency. This is measured in amperes, or amps. An amp is equal to 6.28x10 to the 18th electrons flowing past a given point per second. Think about that. That is a metric fuckton of little negatively charged jobbers being transferred from valence ring to valence ring of the atoms within the conductor.

As a result, work is done based upon the design of the load but heat is also created within the conductor. This is due to friction. As an example, do the Mr Miaggi wax on wax off hand rub thing. The more vigorous you wax it off the hotter your hands get. So from this we can see a limitation of any conductor is heat. The more electrons flowing the larger the conductor needs to be. A 12 gauge copper conductor can, per the NEC code book, can have no more than 25 (I think) amps flow through it. However, it is only allowed to be protected by a maximum 20A OCPD (overcurrent protective device) but that is a different discussion.

A 500kcmil (kilo-or thousand- circular mil) conductor can have up to 380A flow through it per the NEC. This is all based on the 75degree Celsius scale in table 310.15(B)(16). This table was formerly 310.16 up through the 2008 NEC & was changed in the 2011 edition. Reason being is that tables in the NEC are numbered based on the section that refers you to said table. There never was a Section 310.16. But back to the amperage thing...

So, this 75degree scale is what I personally always use, as opposed to the 90degree scale, because damn near all lugs on a breaker are rated for 60/75degrees but not 90. You see, any circuit rating is only as strong as its weakest link. If a conductor is sized based on the 90 scale but the lug isn't, than the lug will potentially get hotter than it is rated for and fail. Now some of you are saying that there are lugs rated for 90degrees and you would be correct but many circuit breakers are not made with these lugs. Always check the temp rating of your termination lugs. Look for a marking like 'AL9CU' or 'CU9AL. The letters mean that it is rated for both copper & aluminum while the 9 means that it is 90degree rated. If the '9' was a '7' than it is only rated for 75degrees.

Okay, where was I...oh yeah ---> amperage flows from the source, through the load, & than back to the source. Amperage, or current, should NOT flow within the grounding system. All of the green wires in the system are there for safety. There are different names for different parts of a grounding system based on where it is within the system. The part that makes the physical connection to the earth is the grounding electrode. 250.52 allows for the following types of electrodes: rod, pipe, plate, ring, concrete encased (commonly called a ufer, named after some guy named Ufer because he founded the use of this type of electrode), steel structure of a building, underground metal water pipe, and probably a couple more that I can't remember right now. There are restrictions to material type, install method/rules and such but I ain't going there right now.

The conductor that connects this electrode to your panel/switchgear is the grounding electrode conductor. This is sized based on the equivalent size of the service entrance conductors and isn't required to be larger than 3/0 ( that's 3-ought or 000). You see, on the American Wire Gauge scale the larger numbers are smaller wires and as the wire gets bigger it's AWG number gets smaller. Example being numbers going as such:12, 10, 8, 6, 4, 3, 2, 1, 0(1/0 or 1-ought), 2/0, 3/0, and finally 4/0. From here, the size is simply the circular mills of the conductor starting with a 250kcmil, 300, 350, 400, 500, 600, 750 and so on up to 2000. 750 is a big bitch, I couldn't imagine pulling 2000's!!! Who of you still call a 500 like this---> 500MCM? This is old terminology that means the same thing as kcmil. The first M is the Roman numeral for 1,000 just like k is the metric prefix. The CM than means circular mils.

What is this unit of circular mils that I speak of? It is an area measurement specific to conductor sizing. A mil is a linear measurement equal to one/thousandth of an inch. A circular mil is mils times mils. This formula is not like the area of a circle measurement which is (pi)(r)(squared). Why does the area of s conductor differ from the area of a circle you ask? I ain't sure except to probably get to a much more specific number for it value. A 12awg is 6530 mils, a 10awg is 10,380 mils & I don't remember any others right now. We can talk raceway fill (based on area) and box fill (based on volume) but that's a whole different discussion so back to grounding.

The conductor that connects the grounding conductor to the grounded conductor at the service is the main bonding jumper (system bonding jumper at a seperately derived system such as a transformer). This can be a wire, bus bar, or screw depending. I'm sure you are wondering what this 'grounded' conductor is that I spoke of? This is the system conductor that is intentionally grounded & is commonly called the neutral. It isn't always a neutral and could be a corner of a corner grounded delta but... This neutral is identified by white or gray insulation or black insulation with white or gray tale at its termination points. The neutral IS a normally current-carrying conductor. In your house on a 120v ckt the black, ungrounded 'hot' wire is where the current starts to flow through the circuit conductor toward the load. The neutral is the return path for this current back to the panel to the neutral bus, through the grounded service entrance conductor and finally back to the source or transformer winding(s).

The grounding conductor is the conductor that is continuously performing the grounding, or making the connection to, the metal non-current carrying parts n pieces of all the things. There should NOT be any current flowing on this conductor. This is the green, or bare conductor. What is the purpose of this grounding conductor? It's three fold actually: to put all non-current carrying metal parts at the same potential as the earth (remember the grounding electrode, grounding electrode conductor and main bonding jumper), to perform bonding duties & to be able to safely carry ground fault current to help facilitate the operation of the OCPD. Ground faults are typically high current faults that can be 1,000's of times higher than normal current values. During a ground-fault LARGE amounts of current flow from the source, through the circuit breaker, through the grounding system and back to the source. This is why the secondary windings of a transformer are grounded & why the main bonding jumper is what it is. The main bonding jumper provides a path for this fault current to flow back to the transformer. The circuit breaker says OH SHIT THIS IS WAY TO MUCH CURRENT!!!!! I NEED TO OPEN MYSELF UP!!!! Hopefully it does, as opposed to blowing the fuck up. You see, any OCPD has a rating called its AIC (amps interrupting current). This is the amount that an OCPD can safely have flow through it before it blows the fuck up.

Gear has an SCCR rating (shirt-circuit current rating). Kinda the same but more specific to the bussing in the gear. The higher the rating the more, stronger the bracing for the bussing. I mentioned that heat is created when current flow but one more thing happens. A magnetic field is created when current flows. Copper is non-ferrous (can't be permanently magnetized) but can become an electro magnet. Basically to magnetize a material you need to align many many of the atoms within it. During current flow some of the atoms, specifically electrons, all flow the same direction and work together so that their individual magnetic fields add to each other. The higher the current, the stronger the magnetic field. High faults can easily cause wires to slap around in conduits or for bus bars to be physically attracted to each other (bent like a motherfucker) until they possibly touch each other and blow the fuck up!!! KA-FUCKING BOOM!!!!

I can get deeper into this, explain how transformers and motors work, what voltage, resistance & power are, how to bend conduit in every way, and a bunch of other shit but I need to stop typing so I can get back to chugging my Keystone Lights.

TL:DR OP doesn't understand electricity.........

What I though.  There is a light circuit, (overhead flourescents) two different higher voltage circuits and outlets. Attached File


Outside GFCI Attached File

Inside GFCI (literally the other side of the wall and stomach level. Attached File


Then clockwise around the shop. Attached File
Attached File

Attached File
Attached File

GFCI is wired backwards

This and you can have 2 GFCI's on the same breaker.  Read the instructions you can wire them so that if one trips the other still has power.

Attached File

Attached File

One thing to look at is the amperage rating of the GFCI, there are 15 and 20 amp GFCIs. A 15A will not work on a 20A circuit and vice versa.

It looks like he has white to silver, but hard to tell for sure......

Attached File
Attached File
Attached File

The guy who owned my house liked to overdo things.  And really liked labeling them.  Like, when he wired the shed for electrical service, he labeled the incoming lines as "hot", "neutral", and "floating ground". After I finished crapping my pants and cutting power, I looked closer and he apparently meant "unbonded ground tied to the ground in the main panel" (which is how it should be done).  

They also remodeled and rewired the kitchen.  The counter top outlets are on two circuits, alternating A and B.  And every one of them is its own GFCI outlet.  Not GFCI-protected, with the GFCI in the outlet closest to the panel.  Every one of them is its own GFCI.

I would check the line and load on the gfi also check that you have the same white and black wires paired together

Attached File

Thanks for the help and advice.  I replaced the new GFCI as upon further checking I was given a 15A rather than a 20A.  Thought I asked for 20A.  Bought a 20A ..... Anyway it all works now.  Even the outside GFCI.

Really?

I have actually grabbed a 15A GFCI by mistake and it would not work on a 20A circuit.

Attached File


Old one in brown that failed.  New one on right that happened to be 15A but more importantly had the line and load switched causing it to not work...yes someone warned me but I assumed (incorrectly) that “they’re all the same”...funny, that’s what the person at the electrical supply said.  Got another GFCI at Ace Hardware and made sure it was 20A and voila, it worked...because it had the same line and load orientation as the original.  Outside GFCI was ok.

Learned something