Can a load center have a breaker as large as its main?

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ActionDave

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If I understand your description you have the breaker hooked up wrong.

Both of the circuit conductors go to the breaker. The black to the terminal marked load and the white to the terminal marked "Load Neutral" The white wire on the breaker goes to the neutral buss.
 

Leejosepho

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If I understand your description you have the breaker hooked up wrong.

Both of the circuit conductors go to the breaker. The black to the terminal marked load and the white to the terminal marked "Load Neutral" The white wire on the breaker goes to the neutral buss.
You understood correctly, and I am glad my description was clear! I had the circuit's white wire going directly to the neutral bar, and that left the AFI finding no neutral to monitor when a load was applied. I thank you.

Overall, however, I am still wondering whether I yet have the kind of protection I am looking for like when I had the circuit's black shorted directly to ground and no breaker tripped. To test that kind of scenario with this AFI breaker now installed, I just placed a temporary load (a 60W bulb and my 3/8" drill) between the AFI circuit's black wire and the panel's ground, and that did not trip the breaker. Like I had mentioned earlier, I have continuity between the neutral bar and ground even though the panel is not bonded ... but shouldn't that AFI breaker have noticed (during my test) that not all of its current was coming back through its white wire?

Most important of all: I want to reconnect the receptacle out in the yard, and I am wondering whether it would be best (or maybe even required?) to use a GFI outlet out there even though its power will be coming through the AFI breaker ...

The crazy history of all of this is that my father-in-law had put that outlet out in the yard many years ago so he could use it to squirrel-proof his bird feeder, and now I want to keep that outlet out there for the legitimate purpose of a small fountain pump for a birdbath setup, and I want it to be completely safe for squirrels and humans, alike.
 
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ActionDave

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You have a lot going on in that head of yours(reference to profile picture).

Continuity between the neutral and ground bar is a good thing. It has nothing to do with ground rods. It has to do with tripping breakers under fault conditions.

GFCI breakers protect people and do it very well if they are hooked up properly and tested regularly.

AFCI breakers share some of the technology of GFCI but are not intended to protect people from a shock. They are not a substitute for GFCI protection.
 

JWelectric

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Lee

Sorry but I am not at home and my time is very limited on the internet for answering questions like this..

First the ground rod or electrode system does nothing to prevent someone from being shocked or to open an over current device. Forget about the electrode after installing the system. The grounding electrode system be it rod pipe plate or whatever is there in case lightning strikes and nothing more.

It is the connection between the equipment grounding conductor and the neutral at the service that prevents things from happening. In this installation the absence of the equipment grounding conductor with the feeders mandates that the neutral and equipment grounding conductor be bonded together in that small panel or the equipment grounding conductors are useless and just if they weren’t installed.

Either install the bonding screw or run an equipment grounding conductor along with the feeders to the remote panel. Under the 2011 NEC the equipment grounding conductor must be installed with each and every installation
 

ActionDave

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Hey jw, in the photo the feeders are in emt and there is no bond at the sub-panel, which would be correct. Where are you seeing no egc?
 

JWelectric

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Hey jw, in the photo the feeders are in emt and there is no bond at the sub-panel, which would be correct. Where are you seeing no egc?

The breaker did not trip when the connector cut through the conductors. This means that there is no equipment grounding path back to the neutral or the EMT is not electrically continuous from one panel to the other.
 

Leejosepho

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Lee

Sorry but I am not at home and my time is very limited on the internet for answering questions like this..
I definitely appreciate your and everyone else's time spent here, and I thank each of you.

Either install the bonding screw or run an equipment grounding conductor along with the feeders to the remote panel. Under the 2011 NEC the equipment grounding conductor must be installed with each and every installation
I will install the bonding screw for now and then see what the electrician and/or inspector might say (if the inspector even looks at the workshop) when my service entrance at the house is updated.

@ActionDave: I apologize for my first photo and post not being completely clear about the EMT not being electrically continuous back to the main panel.

You have a lot going on in that head of yours (reference to profile picture).
I have Asperger's Syndrome and I am a bit like Temple Grandin: I think in pictures. Hence, and especially when I do not know specific details like when dealing with some of the stuff in this thread, my only option is to verbalize as much as possible and then listen for informative feedback!

AFCI breakers share some of the technology of GFCI but are not intended to protect people from a shock. They are not a substitute for GFCI protection.
Well then, that answers the question about the yard receptacle and I will install a GFCI. I thank you.

If you have a moment to enlighten me a bit, what would be a typical scenario where an AFI breaker would catch a problem? Or, is there really any good reason for my having the AFI breaker for my workshop lights and receptacles?
 
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Leejosepho

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Okay, now what?!

I went out and installed the bonding screw, and now it only takes a 60W bulb to trip the AFI breaker. Prior to bonding the panel, the circuit connected to the AFI worked fine.

Do I still actually have a problem somewhere, or is the AFI just not working well in a bonded sub-fed panel without an equipment ground running back to the main panel at the house?
 

Ballvalve

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As to the picture, I realize well, that life is full of hideous twists and turns that no one deserves.

Not to be rude, but to save a life, wear some heavy rubber stompers when working on this strange panel or picture flames coming out of the top of your head.
 

Cookie

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No, Lee, something, somewhere is really really wrong. I don't mean to be rude either, but, honestly, Lee, it is time to just wait for an electrician. Ballvalve's description of that picture is right this time, Lee. He is right Lee. Time to stop working on it, Lee. I would. So far, you have been lucky Lee. It is time to put away all the tools, call an electrician if you haven't, make an appointment and get him out there as soon as possible. Something is not right Lee. You might get hurt. Put away the tools, go inside and call one, make a cup of coffee and call it good for right now. And, let us all know later, what he did and how it is going. okay?
 
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JWelectric

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It is not the bulb that is tripping the AFCI device but something else. It might pay you to redo some of the things you have done with the installation of the circuits as it sounds like there might be some major issues.

Cookie offers some sound advice. Be sure that it isn’t one of those good old boys that can save you a hand full of dollars as most of them have no more knowledge than you.
 

Leejosepho

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It is not the bulb that is tripping the AFCI device but something else.
Prior to my bonding the panel, the AFI breaker worked fine all the way around. All the light bulbs lit and I could run my drill press, bench grinder or whatever else without tripping the breaker. After I had bonded the panel, the small AC adapter providing power for the speakers for my iPod was all the AFI breaker would/could power before tripping.

It might pay you to redo some of the things you have done with the installation of the circuits as it sounds like there might be some major issues.
With the panel's main breaker off, I have no continuity between any black and the panel's neutral bar or any black and the panel's ground bar. Every box anywhere is grounded, and all connections in any box are twisted and nutted, including ground wires. I remember people complaining about AFI breakers being troublesome a few years ago, and these two I have are older ones from the used panel the electrician is going to install at our house ... and that leaves me far more suspicious of them than of there being trouble in my workshop. In any case ...

Prior to bonding the panel, I did have continuity between the panel's neutral bar and ground, and that did not seem right to me. So I will go out there this morning and try to figure that out. I will turn off the feed breaker at the house and disconnect all white and ground wires in the workshop panel and check for continuity anywhere and report back. Overall, however, the simple question here is this:

What could make an AFI breaker trip when a 60W load is applied after the panel has been bonded?

Cookie offers some sound advice. Be sure that it isn’t one of those good old boys that can save you a hand full of dollars as most of them have no more knowledge than you.
Cookie means well, but we are now way past the matter of safety while working on anything. We are now dealing with a problem that seems to have everyone baffled and we will see who might finally get it figured out! Also, the electrician who has me on his project list is definitely not "one of those good old boys" who cannot be trusted to do things properly ... and at the same time, neither is he one of the arrogant and/or self-righteous types who judge their customers by their own knowledge (or lack of it) and/or the sizes of their wallets.
 
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Cookie

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I don't know what to say.
I hope you get it fixed.
 
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Leejosepho

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I don't know what to say.
I hope you get it fixed.
I thank you, and I have ... and now for a friendly, tongue-in-cheek moment ...

Whew, Cookie, I never could have imagined you had the connections to have the power turned off to the entire city here while I was out looking for that problem this morning! However, and just a few minutes after I had posted, a three-hour blackout began ...

How did you do that?!

**end of tongue-in-cheek moment**

Even though the power was out everywhere here after I had first posted this morning, I still turned off the feed from the house to the workshop and then went to work looking for the neutral-to-ground continuity that should not have been there without the box being bonded ...

... and I did find a white wire in the lighting circuit that was lightly pinched between a porcelain light fixture and the grounded box to which that fixture is attached. So, I have corrected that problem ...

... and now I no longer have any continuity between the workshop-panel's neutral bar and ground unless/until the bonding screw is in place (which it now again is, of course). Overall, however, none of the above directly explains why/how an AFI breaker could/would work fine with plenty of load while the panel was *not* bonded and then trip over a 60W bulb while the panel *is* bonded ...

... and here is my theory: The neutral wire for the feed to the workshop does/did not have a perfect connection at the supply panel at the house -- it has a twisted connection to an extension wire connected to the neutral bar, and I have since added a nut to that years-old twist -- and then the pinched wire under the light in the workshop was not a complete-and-solid connection (such as the actual bonding screw at the panel would have provided if it had previously been there). So then, and prior to my bonding the panel, very little current actually went to ground through the pinched wire in the light box, and that means the AFI breaker detected no problem until I actually bonded the panel and more current actually did go directly to my ground rod rather than back through the feed's neutral wire's poor twist connection at the house.

Does that make sense?!

If so, that might answer my question as to the purpose of even having an AFI breaker.

As an aside here: The EMT misunderstanding at the beginning of this thread initially left me thinking the workshop panel should *not* be bonded, and it was then really a good thing that the ground rod did accept most of the current from the black wire that was inadvertently shorted at the clamp at the top of the panel at that time. Barefooted or not, that EMT misunderstanding and its accompanying comment suggesting big trouble if the workshop panel *was* bonded would have left me receiving a full-voltage shock rather than a mere tingle if the ground rod had not done what it had done by instead taking almost everything on into the ground.

None of us is perfect, of course, but we sure do need to be wary of mere assumptions and non-clear implications, eh?!
 
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Cookie

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How very funny that was and something you should say!

I hailed from a long line of either welders or sparkies. I was 9 when I discharged my first capacitor. I loved playing with my dad's diodes and stripey colored-banded triodes. I learned early that tubes have a pressure which can implode. I knew what a schematic was before I saw the book, See Spot Run. In first grade when the teacher said to take out your reading book, I asked her, where she kept the schematics at. At 16 my dad said, I should take the exam for a third class license, I did. By the time I was 21, I had them all. He used to say, meaning this as a compliment to me, " that you are smarter than you look." I used to look in the mirror and wonder, is it the boobs? or he mascara? Then, I met this man. Who was what? A sparky... And, he was irish... My dad was so happy. He looked like a little leprechaun dancing. He wasn't racist at all, he just liked it he was irish. At my girlfriend's wedding he said, " I was talking to that tall kid, that tall skinny kid with the red hair, I think you should get to know him." And, what happened, I married him.

So, their in the evenings, we would work on our new house. It was bought "as is." And, boy was it as is. My dad ripped out all the electrical in most of the house, and my husband ripped out the kitchen tracing a hot wire. I was out buying the right gauge wire, nuts, and pizzas.

It was a match made in heaven. Between my husband and dad. :)
God they loved him. If we had an argument, I was told, without them even hearing about it, I was at fault, not him!

I rethought this marriage bit, lol. I was getting the shaft.

We were a sparky family. We have sparky children.

When he passed on, I was told by his coworkers and the military that God needed the best sparky so their wouldn't be anymore blackouts.

We lit up the town that night better than any 4th of July Celebration.

So, you see, in essence, I do have connections. That blackout was God's way of saying, " call a sparky!" Things happen for a reason.

Call.
 

JWelectric

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Lee

Arc-fault devices are designed to detect arcs in the circuit. They will have some level of GFCI protection but not enough to protect someone from being hurt. Most will be in the 70 milliamp range or larger.

You made a comment about current going to the ground rod which is not what is happening unless you have a lot of iron in the soil in your area.
then really a good thing that the ground rod did accept most of the current from the black wire that was inadvertently shorted at the clamp at the top of the panel at that time.
Around here most rods will have a resistance of 300 ohms or greater. At 120 volts this would only allow a maximum of 400 milliamps to flow through the rod and would not have any effect on the arc-fault device or any other device. You need to forget about the rod allowing current to flow and remember that the rods are installed to dissipate lightning not for current to flow on. The rod does not have any effect what so ever on the wiring system.

Any and all current must return to its source and not even one electron will be leaked into earth. Earth will and does conduct current when the voltage is great enough to push current through the dirt.
One fact that is always true is Ohm’s Law which states that the voltage divided by the resistance will equal the current that flows. Using the requirement in 250.56 of 25 ohms do the math at 120 volts and then use the voltage on the primary of your transformer to see how much current will flow. If you don’t know what it is in most cases it will be 7200 volts. At 120 it is just over 4 amps but at 7200 it will be over 200 but in any case it is trying to return to its source.
 

Drick

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...and more current actually did go directly to my ground rod rather than back through the feed's neutral...

Your ground rods are for lightning protection. They will not accept power that has been generated by your power company and magically suck it into the ground. The earth is a lousy conductor of electricity.

Arc faults are conceptually fairly simple devices. They monitor the power going out on the hot wire and returning on the neutral wire. This is why you must connect both wires to the arc fault breaker. The amount of power on each wire should be the same. When it is not the arc fault trips.

Now you said you had a pinched neutral wire in a light fixture. This will cause an arc fault to trip because some of the power can now take a detour around the arc fault via the accidental neutral wire to ground wire connection created by the pinched wire. BUT you did not have the bonding screw installed!! SO the power could not make it back to the service conductor neutral. Your ground wires were essentially a dead end road going nowhere and doing nothing. When you installed the bonding screw you connected all the ground wires to the service conductor neutral and suddenly power on the ground wires had a place to go! Now when you turned on the light the arc fault detected that not all the power was returning on the neutral and tripped!


Well I suppose you are still wondering why you have grounded outlets in the house and are thinking that they must have something to do with the ground rods. Well they don't. The ground wiring protects you from electric shock by (hopefully) tripping the circuit breaker. As an example, if the hot wire in your shop light suddenly broke off inside the fixture and came in contact with the grounded metal frame of the fixture it would cause a dead short. All the power leaving the breaker on hot wire would immediately return on the ground wire which is of course connected to the service conductor neutral via the bonding screw. The current would likely be in excess of 1000 amps. Your 15 or 20 amp breaker will trip and you will not be electrocuted by the damaged fixture. If you remove the bonding screw from your panel the breaker will not trip!! Your ground rods will not magically suck up enough power to trip your circuit breaker. Now if you touch the fixture you will be electrocuted!

This is a simplified version of how it all works, but I hope it helps.
-rick
 

ActionDave

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... and I did find a white wire in the lighting circuit that was lightly pinched between a porcelain light fixture and the grounded box to which that fixture is attached. So, I have corrected that problem ...

... and now I no longer have any continuity between the workshop-panel's neutral bar and ground unless/until the bonding screw is in place (which it now again is, of course). Overall, however, none of the above directly explains why/how an AFI breaker could/would work fine with plenty of load while the panel was *not* bonded and then trip over a 60W bulb while the panel *is* bonded ...
AFCI breakers have ground fault sensing incorporated into them. However without a proper bond to the neutral conductor, they cannot sense a ground fault.

... and here is my theory: The neutral wire for the feed to the workshop does/did not have a perfect connection at the supply panel at the house -- it has a twisted connection to an extension wire connected to the neutral bar, and I have since added a nut to that years-old twist -- and then the pinched wire under the light in the workshop was not a complete-and-solid connection (such as the actual bonding screw at the panel would have provided if it had previously been there). So then, and prior to my bonding the panel, very little current actually went to ground through the pinched wire in the light box, and that means the AFI breaker detected no problem until I actually bonded the panel and more current actually did go directly to my ground rod rather than back through the feed's neutral wire's poor twist connection at the house.
Close, but you could have a solid connection, on purpose or just as good as, and no breaker would trip if the circuit is fed from a panel that is missing a proper connection to the neutral. When you added the bond screw you made that connection and the breaker worked. The neutral is more properly known as the grounded conductor not because of anything to do with ground rods but because it is connected to the earth by the power company.

If so, that might answer my question as to the purpose of even having an AFI breaker.
They are intended to sense an arcing condition that could lead to a fire. They incorporate ground fault circuitry but are not to be substituted for gfci protection where required.
As an aside here: The EMT misunderstanding at the beginning of this thread initially left me thinking the workshop panel should *not* be bonded, and it was then really a good thing that the ground rod did accept most of the current from the black wire that was inadvertently shorted at the clamp at the top of the panel at that time. Barefooted or not, that EMT misunderstanding and its accompanying comment suggesting big trouble if the workshop panel *was* bonded would have left me receiving a full-voltage shock rather than a mere tingle if the ground rod had not done what it had done by instead taking almost everything on into the ground.

None of us is perfect, of course, but we sure do need to be wary of mere assumptions and non-clear implications, eh?!
Yes indeed, as I was the one who asked about the bonding screw in the first place; assuming that the emt was continuous.
 
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