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

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Leejosepho

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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.
Maybe I do. While the black wire of the receptacle circuit was shorted in the clamp at the top of the panel and the panel was not bonded, that incoming leg showed no voltage when measured across to the neutral bar and the panel (and its ground bar) did show 120V when measured against the neutral bar ... and then measuring across the other incoming leg and the panel (ground bar) showed 240V ... and during all of that, I was only getting a small tingle between the panel and my bare feet when I touched the panel with my finger. So while I do understand the ground rod is not intended to be a catchall for stray current, it certainly did protect me from a full-voltage shock while that one incoming leg was directly shorted to the panel.

As an overall recap here ...

I came asking whether I could install a 30A breaker next to a 30A main;
I was told I could and my mis-belief that my panel should not be bonded was confirmed;
I shorted a wire in a clamp and my ground round spared me from a great shock;
I corrected that problem (the short) and installed an AFI breaker incorrectly;
Someone straightened me out about that and the breaker did not trip since the panel was not bonded;
I bonded the panel and eventually found a shorted white wire under a light and a weak connection for the feed's neutral at the house;
I still do not know precisely why the AFI had tripped, but it has been removed and we all agree my service entrance at the house definitely needs some work.

I have ordered a retainer for the back-fed breaker in the workshop panel;
I have installed a 30A receptacle for the welder and I have ordered a 30A breaker for that circuit;
I have ordered a GFI breaker for the 20A circuit in the workshop so I can re-connect the outdoor receptacle;
I will likely call the electrician again next week to see how far down his project list I might yet be.

I thank everyone for the time spent being informative and helpful here ... and yes, Cookie, especially you!
 
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JWelectric

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I shorted a wire in a clamp and my ground round spared me from a great shock;

This is a very untrue statement and has no merit at all. The ground rod did nothing to protect you from any shock unless there was a lightning strike at the time you touched the panel.

The only thing that kept you from getting a bad shock was the resistance between the source and you.
 

Leejosepho

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This is a very untrue statement and has no merit at all. The ground rod did nothing to protect you from any shock unless there was a lightning strike at the time you touched the panel.

The only thing that kept you from getting a bad shock was the resistance between the source and you.
If what you are saying is true, then I should be able to go out there and put my finger on one of the incoming legs while standing barefoot on the concrete floor and still only feel a small tingle ... unless, of course, the pinch at the clamp was so very slight at the time that the breaker would not have tripped even if the panel *had* been bonded. The things I know for certain, however, are that the shorted leg showed no voltage at all when measured against the neutral bar, and that I had 240V between the other incoming leg and ground. I clearly understand you do not want people mistakenly depending upon a ground circuit to protect them from stray voltage, but the power from that shorted leg was going somewhere other than through its connected receptacle circuit (just beyond the pinch) that showed absolutely no voltage at all for the duration of the short.

Tell me where you happen to believe I am wrong if that is all you can do, but help me understand if you can and will! Are you meaning to suggest all power coming in on that shorted leg simply stopped flowing at the point of the pinch except for "just enough" to give me a small tingle and to show voltage on my meter?
 

BobL43

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If what you are saying is true, then I should be able to go out there and put my finger on one of the incoming legs while standing barefoot on the concrete floor and still only feel a small tingle ... unless, of course, the pinch at the clamp was so very slight at the time that the breaker would not have tripped even if the panel *had* been bonded. The things I know for certain, however, are that the shorted leg showed no voltage at all when measured against the neutral bar, and that I had 240V between the other incoming leg and ground. I clearly understand you do not want people mistakenly depending upon a ground circuit to protect them from stray voltage, but the power from that shorted leg was going somewhere other than through its connected receptacle circuit (just beyond the pinch) that showed absolutely no voltage at all for the duration of the short.

Tell me where you happen to believe I am wrong if that is all you can do, but help me understand if you can and will! Are you meaning to suggest all power coming in on that shorted leg simply stopped flowing at the point of the pinch except for "just enough" to give me a small tingle and to show voltage on my meter?

Interesting questions, but you need to be awayre that it only takes a few milliamps (maybe 5 or so ma) passing through the heart of the average person to be a widow maker. 5ma is almost nothing otherwise. not even enough to light up a little 4 watt incandescant nightlight bulb.
What you felt can be measured with a meter
 

Leejosepho

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Interesting questions, but you need to be awayre that it only takes a few milliamps (maybe 5 or so ma) passing through the heart of the average person to be a widow maker. 5ma is almost nothing otherwise. not even enough to light up a little 4 watt incandescant nightlight bulb.
What you felt can be measured with a meter
I do understand that, and I am trying to be careful about not being deceived by a sensitive meter. For example: After I had found and relieved the second pinch (a white wire in a lighting box) while trying to get rid of continuity between my neutral bar and ground (prior to the panel being bonded), I sometimes saw continuity between the neutral bar and ground and I sometimes did not. I could disconnect the neutral wire coming in with the feed and see no continuity between my neutral bar and ground, but then continuity would again eventually show up a little while after I had reconnected that incoming neutral wire ... and at the time, the only "cause" I could detect/suspect anywhere was the ever-changing cloud cover occasionally blocking the sun! But of course, I do not really believe the presence or absence of direct sunlight was affecting/effecting continuity there. Rather, I just cannot imagine a 5ma leak/short stopping *all* power from being available in the thereafter circuit connected to that incoming leg.
 
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Cookie

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I am still waiting to see a post, saying, you made that call... :)
Sometimes, we just got to do what we just got to do, bite the bullet, spend the hard cash we don't want to part with to hire in a pro...
... this is why, I am poor, but, alive!

I don't do my own surgeries and cook up my own brew to stay alive. Sometimes, Lee, it is what it is.

When in doubt, don't do it.
 

JWelectric

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If what you are saying is true, then I should be able to go out there and put my finger on one of the incoming legs while standing barefoot on the concrete floor and still only feel a small tingle ... unless, of course, the pinch at the clamp was so very slight at the time that the breaker would not have tripped even if the panel *had* been bonded. The things I know for certain, however, are that the shorted leg showed no voltage at all when measured against the neutral bar, and that I had 240V between the other incoming leg and ground. I clearly understand you do not want people mistakenly depending upon a ground circuit to protect them from stray voltage, but the power from that shorted leg was going somewhere other than through its connected receptacle circuit (just beyond the pinch) that showed absolutely no voltage at all for the duration of the short.

Tell me where you happen to believe I am wrong if that is all you can do, but help me understand if you can and will! Are you meaning to suggest all power coming in on that shorted leg simply stopped flowing at the point of the pinch except for "just enough" to give me a small tingle and to show voltage on my meter?

The resistance between the black wire and the short in the clamp was high enough that it would take most of the voltage drop when you come in series with that resistance. Remember that the voltages across the resistors in a series circuit will equal the total voltage applied and the total current of each node of a parallel circuit will equal the total current of the entire circuit.

When you walk up and put your finger to a leg of the feeder supplying the building barefoot then the conductors, you, and earth are the three resistors in series with the connection to earth at the transformer supplying your service therefore all the current is flowing through you back to the source and the amount of voltage across your body will be equal to the differences of the total of the resistance of the other two.

In order for you to have 240 volts between one leg and ground the ground must be energized by the other leg. If there was proper bonding then the shorted leg would have tripped the breaker instead of energizing the grounding conductor.
 

Leejosepho

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I am still waiting to see a post, saying, you made that call...
That is not what any of this is about, Cookie. This is about trying to understand how I was *not* injured when one leg of the power coming into my workshop was directly shorted to ground (at least lightly) and I happened to touch the outside of the panel like anybody at all might have done on any day while just flipping a breaker either on or off for any reason at all.

The resistance between the black wire and the short in the clamp was high enough that it would take most of the voltage drop when you come in series with that resistance.
While you might be completely right there, that statement does not make any sense to me. Resistance somewhere -- something somewhere not receiving all the power available -- is what made it possible for a trickle to come through to me ... and that leaves me wondering why no voltage at all was available to the shorted circuit while I was only feeling a small trickle from the feed to that circuit. Where was the remainder of that power going? Either the pinch had blocked it from going out to the workshop's receptacle or else that power was going into the ground.

When you walk up and put your finger to a leg of the feeder supplying the building barefoot then the conductors, you, and earth are the three resistors in series with the connection to earth at the transformer supplying your service therefore all the current is flowing through you back to the source and the amount of voltage across your body will be equal to the differences of the total of the resistance of the other two.
I think I understand that, and that supports my theory that most of the shorted voltage/power was flowing directly to ground rather than through me. For example:

If I were to go out there right now and touch one of the service legs (and, of course, I certainly will *not* be doing that), then all of that leg's available current (subject to my physical conductivity, of course) would then flow directly through me and to the concrete floor (earth) and I would would likely be gravely injured and the breaker would not trip. But when I did essentially the same thing while that leg was shorted to the panel (and the breaker did not trip because the panel was not bonded), I only felt a small tingle.
 

Ballvalve

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Can you explain that photo with the tarped camper and the well[?] pipe in the air and a tree [?] propping it up?

Is that about leaking electricity?
 

Leejosepho

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Another anecdote here:

One of my brothers used to work in maintenance at a large campground, and one of his first calls ever was related to a camper getting "tickled" by current at one of the campsites. At that particular campground, there were five transformers supplying their respective panels located around the perimeter of the park, and all the neutrals from those five transformers were tied together like a large spider web overhead. Throughout the park, cloth-cover "Romex" was stapled to trees to supply power for night lights, and "arcing to the bark" could be seen whenever those trees were wet (such as with dew in the morning). Worst of all, however, campers who were not carefully standing (as warned) on the insulating mats in the showers were getting serious jolts whenever they touched the shower valves ...

... and no electrician in that area would even come out again and try to do any more corrective work on that overall mess.

My brother is not a "real electrician", of course, but he was all the park owner had available at the time ...

Loosening the staples on the trees (since the owner would not take those wires down altogether) took care of the bark-arcing, and bonding all the boxes at the campsites -- each site had a ground rod -- virtually (but not quite) eliminated the shockings going on there. One observation my brother made was that all the even-number sites were pulling power from one incoming leg of a given transformer -- only 120V available at any site -- and the odd-numbered sites were pulling power from the other, and that factor was causing a persistent imbalance at each transformer since campers were typically assigned to every other site whenever possible in order to afford them a bit more privacy when the park was not full.

In the end, my brother somehow figured out one of the five transformers was bad and convinced the power company to replace it, and nobody was getting shocked at any campsite the last time he was there. The point here, however, is that bonding the camping sites' panels to ground to send stray current there is how he rightly or wrongly shunted the shocking current.
 
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Leejosepho

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Can you explain that photo with the tarped camper and the well[?] pipe in the air and a tree [?] propping it up?

Is that about leaking electricity?
Yes, I can explain the photo, and no, that photo has nothing to do with electricity. That photo came into this thread after someone tried to take a cheap shot and I called him on that.
 

JWelectric

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one leg of the power coming into my workshop was directly shorted to ground
It was not shorted to ground. Nothing and I repeat nothing is ever shorted to ground period. A short is from one conductor to another conductor. From hot to earth is a fault to ground.
While you might be completely right there, that statement does not make any sense to me.
and until it does then there is no way for me to get you to understand anything. The first thing you need to learn is that the ground rod does nothing at all to protect any one
I think I understand that, and that supports my theory that most of the shorted voltage/power was flowing directly to ground rather than through me. For example:
again it does not go to ground it goes back to its source.
would then flow directly through me and to the concrete floor (earth)
and through earth back to the pole which the transformer is mounted on, up the copper wire to the transformer but not to earth itself.
 

Leejosepho

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From hot to earth is a fault to ground ... through earth back to the pole which the transformer is mounted on, up the copper wire to the transformer but not to earth itself.
That I definitely understand, and I thank you. I have heard some of the debates/discussions about "returning power to the earth" or whatever, and I did not mean to be getting into that. So then ...

The short to my panel that is connected to my ground rod made it possible for that mis-directed current to flow back to wherever best rather than through me, and that flow is what essentially robbed my workshop's receptacles of the power they otherwise would have had available. However, and as Jadnashua (sp?) had cautioned early-on here: A ground rod should never be dangerously assumed to always be a never-failing safety shunt.

Please accept my apology: I was not meaning to say "Mother Earth" or whoever/whatever had protected me from the shorted power any more than I believe the outage we had here the other day was any kind of "act of God" ... and I say that with all due respect, dear Cookie! Rather, a trucker somewhere had simply knocked a pole over and caused a lot of trouble for a lot of people, and I just cannot believe God had anything to do with that!

Question: Two neighboring farmers pray ... one for rain for his beans, and the other for no rain so he can harvest his wheat. Whose prayer gets answered?!
 
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Cookie

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Lee, I guess it is hard on these things, via these means to note when someone is just making a joke about something. I was joking about having connections from up above, but, I am not joking, when I say, I think you are out of your element here, not expert enough, and risking your life. That is not funny. On the job training does not apply to electricity. It takes classes, and alot of them to be safe enough.

If you feel you are safe enough then, I call it good. But, I don't agree.

But, what I said about your loss of power being related to my special connections above was just a joke.

I know where my limitations lay and most people do Lee.
 

BobL43

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That I definitely understand, and I thank you. I have heard some of the debates/discussions about "returning power to the earth" or whatever, and I did not mean to be getting into that. So then ...

The short to my panel that is connected to my ground rod made it possible for that mis-directed current to flow back to wherever best rather than through me, and that flow is what essentially robbed my workshop's receptacles of the power they otherwise would have had available. However, and as Jadnashua (sp?) had cautioned early-on here: A ground rod should never be dangerously assumed to always be a never-failing safety shunt.

Please accept my apology: I was not meaning to say "Mother Earth" or whoever/whatever had protected me from the shorted power any more than I believe the outage we had here the other day was any kind of "act of God" ... and I say that with all due respect, dear Cookie! Rather, a trucker somewhere had simply knocked a pole over and caused a lot of trouble for a lot of people, and I just cannot believe God had anything to do with that!

Question: Two neighboring farmers pray ... one for rain for his beans, and the other for no rain so he can harvest his wheat. Whose prayer gets answered?!

In your post #35, you said the white neutral wire was pinched, touching the metal box. A decent load in the garage would cause a measurable voltage on the Neutral due to some voltage drop in the wiring, at the garage end, and probably enough to give you that tingle. If the conduit ground were complete, maybe no shock would be felt, but the pinched neutral would cause a ground fault if carried through a GFCI or
AFCI.
 

JWelectric

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That I definitely understand, and I thank you. The short to my panel that is connected to my ground rod made it possible for that mis-directed current to flow back to wherever best rather than through me, and that flow is what essentially robbed my workshop's receptacles of the power they otherwise would have had available.

Okay then if you understand help me out here.

I bought me a CB radio to put in my truck. I ran a wire from the battery to the red wire on the CB but it won’t come on.
What is that black wire?
Where does it hook up to?
 

Chad Schloss

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lol, nope, trick question. no black wire. chassis is metal and hanging bracket is metal, must be grounded. :) don't you have those dangly straps hanging from the back of your truck to ground it? lightning strips? lol :)
 

BobL43

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lol, nope, trick question. no black wire. chassis is metal and hanging bracket is metal, must be grounded. :) don't you have those dangly straps hanging from the back of your truck to ground it? lightning strips? lol :)

toll collector protectors:D
 
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