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Old 03-17-2010, 05:14 PM   #31
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Bonded = electrically connected.
A switch yoke may be bonded to the neutral bus in the panel by being connected to a series of bare ground wires in Romex cables daisy chained through other outlet boxes. As in "the thigh bone is connected to the knee bone is connected to the calf bone ..."

Grounded = Making electrical contact with the ground as in earth as in dirt or bonded to some object making such contact.
So the switch yoke is grounded when it is bonded to the neutral bus bar which is also the ground bus bar in the main panel and a wire connects said bus bar to a ground rod.

Grounding conductor = Conductor that is supposed to be bonded to ground, that is supposed to render safe to the touch any object bonded to it by (as a conductor) providing a path to ground of lesser resistance compared with the body of someone touching that object, and that is not supposed to carry current between source and load.

Grounded conductor = Conductor that carries current between source (such as a pole transformer) and load and that is supposed to be bonded to ground.
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Last edited by AllanJ; 03-17-2010 at 05:58 PM.
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Old 03-17-2010, 05:49 PM   #32
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I know a lady who went off to college to become a newspaper reporter.

She learned a lot of big fancy words in college...

Her first day at a newspaper job, they told her to *forget* all those big fancy words she learned in college and to not use them in her newspaper stories!

They told her they wanted *all* their readers to be able to understand what she was saying and she should write with words which everyone would understand.

They said that is communicating. When the person who is listening to what you are saying understands what is being said.

Same thing with a medical doctor. Best that they not use "medical terms" when talking to a patient...

Doctor: Would you prefer a transumbilical laparoscopic cholecystectomy?
Patient: Huh?
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Old 03-17-2010, 06:25 PM   #33
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At least we haven't gone Latin! What is the Latin word for Earth?
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Old 03-17-2010, 08:12 PM   #34
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I can do latin. But would we go with the idea of bonding, grounding, and earthing.
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Old 03-17-2010, 08:14 PM   #35
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Quote:
Originally Posted by jlmran View Post
At least we haven't gone Latin! What is the Latin word for Earth?
Terra or...humus



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Old 03-17-2010, 08:37 PM   #36
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Quote:
Originally Posted by AllanJ View Post
Bonded = electrically connected.
A switch yoke may be bonded to the neutral bus in the panel by being connected to a series of bare ground wires in Romex cables daisy chained through other outlet boxes. As in "the thigh bone is connected to the knee bone is connected to the calf bone ..."

Grounded = Making electrical contact with the ground as in earth as in dirt or bonded to some object making such contact.
So the switch yoke is grounded when it is bonded to the neutral bus bar which is also the ground bus bar in the main panel and a wire connects said bus bar to a ground rod.

Grounding conductor = Conductor that is supposed to be bonded to ground, that is supposed to render safe to the touch any object bonded to it by (as a conductor) providing a path to ground of lesser resistance compared with the body of someone touching that object, and that is not supposed to carry current between source and load.

Grounded conductor = Conductor that carries current between source (such as a pole transformer) and load and that is supposed to be bonded to ground.
This is exactly why I think the term 'grounding' is a confusing one. Tell me if I'm wrong here: Based on these definitions, ALL conductors in a service or circuit are grounded. Some conductors are grounded continuously, and some are grounded intermittently. When a light switch is turned to the on position, the hot or energized conductor (black) is now electrically connected to the bulb's element, which is connected to the white conductor, which is connected to the electrical source, as well as the earth. Accordingly, the energized conductor is 'a grounded conductor' when the switch is on. It is a grounded conductor that will shock you! But it is not the connection to the earth that allows the bulb to shine brightly. Likewise, it is not the earth connection that provides an exclusive measure of safety to equipment structures. The earth connection only provides a measure of safety if the 'neutral' conductor between the transformer and the service panel becomes compromised (open). There are also implications with lightning...but lets not go there now.

Last edited by jlmran; 03-17-2010 at 08:47 PM.
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Old 03-17-2010, 09:28 PM   #37
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Quote:
. Some conductors are grounded continuously, and some are grounded intermittently.
. I understand what you are saying but it is simply wrong to consider a hot conductor as being grounded due to it feeding through a load.

and just to really confuse your statement:

what about a 240 volt feed. Is it ever grounded?

is there ever a time where a hot conductor is not grounded in your screwed up way of looking at things?


Quote:
The earth connection only provides a measure of safety if the 'neutral' conductor between the transformer and the service panel becomes compromised (open)
and how is that?

Quote:
But it is not the connection to the earth that allows the bulb to shine brightly
I don't think anybody has claimed that

.
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Likewise, it is not the earth connection that provides an exclusive measure of safety to equipment structures.
actually, that isn't true. by earthing one point of the supply, it allows that source to have a 0 potential to anything bonded to it as well as to earth. If you remove the earth bond, you could get shocked on a neutral. Bond that neutral to earth and you remove the potential between the neutral and earth.

Quote:
There are also implications with lightning...but lets not go there now.
why? that is one of the prime reasons you earth ground a point of the supply.

from the NEC 250.4 (A)(1)

Electrical system grounding. Electrical systems that are grounded shall be connected to earth in a manner that will limit the voltage imposed by lightning, line surges, or unintentional contact with higher-voltage power lines and that will stabilize the voltage to earth during normal operation.
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Old 03-17-2010, 09:43 PM   #38
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I'm not saying its right to 'consider' an energized conductor as grounded, I'm saying it fits the definition.

240V circuit? True...hot conductors are not grounded through the circuit in question (example: certain motors, heating elements)

Screwed up way of looking? I'm simply following the definitions.

Nap - Could you provide an example of a potential between neutral and earth?
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Old 03-17-2010, 10:03 PM   #39
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Quote:
=jlmran;416272]I'm not saying its right to 'consider' an energized conductor as grounded, I'm saying it fits the definition.
but it does nothing but confuse the situation.

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240V circuit? True...hot conductors are not grounded through the circuit in question (example: certain motors, heating elements)
well, if this is a residential service, are not both of those conductors connected to ground via the neutral? After all, the neutral is a center tap of the windings that supply the 240 volts. The neutral is earth grounded and since the winding is one continuous wire, both of the 240 legs are grounded in your unique way of looking at this. Wouldn't that mean that every conductor is s grounded conductor all the time? (in a split single phase power supply)

see what happens when you start such an odd way of looking at things?


btw: the other question: 3 phase ungrounded delta supply

Quote:
Screwed up way of looking? I'm simply following the definitions.
No, you are attempting to alter the definition by using the strictest interpretation of the terms and the physical design of an electrical system.

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Nap - Could you provide an example of a potential between neutral and earth?
Huh? if the neutral is earth grounded, there would be no potential. Thats the point (or at least one of them) of earth grounding the neutral.
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Old 03-17-2010, 10:13 PM   #40
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Huh? if the neutral is earth grounded, there would be no potential. Thats the point (or at least one of them) of earth grounding the neutral.
Wait...go back to your earlier post where you stated: "If you remove the earth bond, you could get shocked on a neutral. Bond that neutral to earth and you remove the potential between the neutral and earth."

If you remove the earth bond, then how is there a potential between neutral and earth?

Maybe you're thinking of removing the earth bond only at the service entrance, and I'm thinking of removing the earth bond at the service entrance as well as the power supply (utility poles, etc.)

Maybe that is our confusion.

If the distribution system wasn't bonded to earth, then our houses wouldn't need a bond to earth. But as we both stated earlier, lightning ruins that idea.
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Old 03-17-2010, 10:18 PM   #41
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I should qualify bonding as something done at construction or installation time, as opposed to during utilization. Also, bonding refers to making an essentially resistance free connection which would rule out bonding of a hot conductor to ground by switching a light on.

In a household 240 volt circuit, neither current carrying conductor is grounded.
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Last edited by AllanJ; 03-17-2010 at 10:22 PM.
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Old 03-17-2010, 10:21 PM   #42
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BTW, Nap...you are correct. That which is practical and that which is academic are often two separate worlds. I often am criticized for pushing the academic angle too far. Thanks for corraling me in.

But, surely you can admit that the definitions maybe could use some modifications? If anything to help folks like me?
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Old 03-17-2010, 10:23 PM   #43
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Quote:
Originally Posted by AllanJ View Post
I should qualify bonding as something done at construction or installation time, as opposed to during utilization. Also, bonding refers to making an essentially resistance free connection which would rule out bonding of a hot conductor to ground by switching a light on.
FINALLY...someone introduced resistance. Thanks Allanj. That is the ultimate qualifier.

Definitions versus intentions...its a human flaw.
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Old 03-17-2010, 10:36 PM   #44
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Quote:
Originally Posted by jlmran View Post
BTW, Nap...you are correct. That which is practical and that which is academic are often two separate worlds. I often am criticized for pushing the academic angle too far. Thanks for corraling me in.

But, surely you can admit that the definitions maybe could use some modifications? If anything to help folks like me?
I'm glad you came to your senses. As I said several times, I do understand where you were coming up with your definitions. It is just not how the NEC and the rest of the world define those terms.

it doesn't really matter what you call something as long as everybody else calls it the same thing.

hear is something for you to think about ;

the color blue

define it
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Old 03-17-2010, 10:48 PM   #45
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Originally Posted by nap View Post
hear is something for you to think about ;

the color blue

define it
Very ironic you should ask. The following is a document we use at work quite often to define colors. I didn't just go find this, we really do use it.

http://www.hunterlab.com/appnotes/an08_96a.pdf

When I was young, I would drive my parents nuts by asking them, "If I had your eyes in my head, would I see colors the same way?" Seriously.
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