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240v only system - neutral ground bond

The definition of neutral is "the grounded conductor".
It's called neutral because it poses no Hazzard in regards to exposed grounded metal parts.
If it's not grounded, it's just another circuit conductor.
I'm not trying be a douche. But that's just not true. I'll let the NEC define it.
 

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So when a system is required to be grounded, and that system contains a neutral, the neutral is the point to be grounded. But ungrounded systems exist, and some have neutrals. For example, a center tapped transformer may not be grounded, but the mid point of the winding is still the neutral.

On the other hand, say you have a 2-wire 120 volt service, like was common in the 1920s. That circuit would have no neutral but one of the wires would still be grounded. 250.26 details it pretty good.
 

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The NEC is slowly trying to remove the word "neutral" from the code. Because of the confusion it creates.
It's mostly referred to as "the grounded conductor" because of this. But, they are having trouble doing so. Because all neutrals are grounded conductors. But not all grounded conductors are neutrals. (Example is a corner grounded delta system)
 
The NEC is slowly trying to remove the word "neutral" from the code. Because of the confusion it creates.
It's mostly referred to as "the grounded conductor" because of this. But, they are having trouble doing so. Because all neutrals are grounded conductors. But not all grounded conductors are neutrals. (Example is a corner grounded delta system)
Again, though, just because most neutrals we encounter are grounded, doesn't mean that a neutral has to be grounded to be a neutral. A neutral in a 3 wire single phase system is a neutral whether it is grounded or not. The center point in a 3-phase 4-wire wye system is neutral whether it is grounded or not.
 
Again, though, just because most neutrals we encounter are grounded, doesn't mean that a neutral has to be grounded to be a neutral. A neutral in a 3 wire single phase system is a neutral whether it is grounded or not. The center point in a 3-phase 4-wire wye system is neutral whether it is grounded or not.
That's only if you are reading the 2023 revision of the NEC. This is the latest attempt to make it less confusing. But is only creating more confusion. It will undoubtedly be changed again. But we are stuck with it for 3 years. Not many jurisdictions are going to adopt the 2023 edition. (Except maybe California. But we won't count them)
But for now, we have a 3 year mess coming.
You're just one of the first people to step in the dodo. lol
 
Picture this: Let's pretend that you get 120 volts from a single battery. Putting two batteries in series gives you 240 volts. The mid point between the two batteries is called the neutral and is grounded. So if you measure from the neutral to the "end" pole of either battery, you'll see 120 volts, but if you measure between bothe end poles, you'll see 240 volts. Following? The 240 volt circuit is protected by virtue of being grounded in the middle. You can then connect any end pole to ground because that would be the same as shorting one battery.

Keep in mind this is just a simplified analogy using batteries. Here's a diagram of how a utility transformer makes the hots and neutral. The neutral is grounded and you can see why no other line can be.
This is very helpful information. Thanks.
 
Think of the neutral as the drain. The hot is the power source or faucet. The ground is the emergency overflow drain.
 
Think of the neutral as the drain. The hot is the power source or faucet. The ground is the emergency overflow drain.


I thought that's how it works with DC , power comes from neg ( - ) and goes to pos ( + )

but with AC (alternating current) doesnt the power come down both sides , one then the other, at 50hz ?
 
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Thanks for this explanation.

So then how come one at least one hot leg is not bonded?

Bonding the neutral protects the 120v circuit but what protects the 240v circuit? The same bonded neutral?
H1 + H2 + Ground/bare/green is 240V
If the Ground/bare/green gets to participate it trips the breaker.
 
That's only if you are reading the 2023 revision of the NEC. This is the latest attempt to make it less confusing. But is only creating more confusion. It will undoubtedly be changed again. But we are stuck with it for 3 years. Not many jurisdictions are going to adopt the 2023 edition. (Except maybe California. But we won't count them)
But for now, we have a 3 year mess coming.
You're just one of the first people to step in the dodo. lol
Sorry, the doodoo is on your shoe! This has nothing to do with the version of the code, because that is largely unchanged as far back as I have code books, which is the 1984 edition. I'm not confused about this in the slightest.

Let's try this: Say you have a generator producing 120/240 volts on 3 wires, black, white, and red. It is sitting on a truck, insulted from the ground and no wire is grounded. What do you call the white wire that is equipotential between the black and red wires?
 
Sorry, the doodoo is on your shoe! This has nothing to do with the version of the code, because that is largely unchanged as far back as I have code books, which is the 1984 edition. I'm not confused about this in the slightest.

Let's try this: Say you have a generator producing 120/240 volts on 3 wires, black, white, and red. It is sitting on a truck, insulted from the ground and no wire is grounded. What do you call the white wire that is equipotential between the black and red wires?
That is a floating neutral possibly. It still might have ground and neutral bonded in the generator.

For some reason you are being argumentative, quite possibly because you think like most when it comes to 240V AC split phase systems.

Let's ask this question first to determine your thought process. Is 240V AC split phase 2 phases operating 180 degrees apart?
 
Sorry, the doodoo is on your shoe! This has nothing to do with the version of the code, because that is largely unchanged as far back as I have code books, which is the 1984 edition. I'm not confused about this in the slightest.
Neutral has always been the grounded conductor.
Until 2023. Which is why it will create all the confusion. Luckily it won't be widely adopted. And hopefully the code board will do better in 2026.
Sometimes it seems like they change things just to justify their jobs.
Let's try this: Say you have a generator producing 120/240 volts on 3 wires, black, white, and red. It is sitting on a truck, insulted from the ground and no wire is grounded. What do you call the white wire that is equipotential between the black and red wires?
Common
It's the Common point between the two.
It's not a neutral because it's an ungrounded system.
At least not until "you're" jurisdiction adopts a code edition that says it is.
Could also be called the center tap. But that's mostly used when describing transformer output.

It's one thing to quote from a book that doesn't actually apply anywhere yet. And a completely different thing to speak from 40 years of knowledge and experience. I don't blame you for your position. Given what resources you have to go on.
For now, we'll just have to agree to disagree.
 
That is a floating neutral possibly. It still might have ground and neutral bonded in the generator.

For some reason you are being argumentative, quite possibly because you think like most when it comes to 240V AC split phase systems.

Let's ask this question first to determine your thought process. Is 240V AC split phase 2 phases operating 180 degrees apart?
I'm not being argumentative. I'm stating facts backed by definitions from sources. You are right, it is a floating neutral. A NEUTRAL. My point is that a neutral is a neutral whether it is floating or grounded. Grounding does not factor into the definition of a neutral. But most neutrals are grounded.

And no, 240 VAC "split phase" is not actually two phases 180 degrees apart. It is one single phase tapped in the middle. If striving for accuracy in electrical terminology is argumentative, then I'll be that.
 
Neutral has always been the grounded conductor.
Until 2023. Which is why it will create all the confusion. Luckily it won't be widely adopted. And hopefully the code board will do better in 2026.
Sometimes it seems like they change things just to justify their jobs.

Common
It's the Common point between the two.
It's not a neutral because it's an ungrounded system.
At least not until "you're" jurisdiction adopts a code edition that says it is.
Could also be called the center tap. But that's mostly used when describing transformer output.

It's one thing to quote from a book that doesn't actually apply anywhere yet. And a completely different thing to speak from 40 years of knowledge and experience. I don't blame you for your position. Given what resources you have to go on.
For now, we'll just have to agree to disagree.
It is a common and it is a neutral. It is called "neutral" because it is in between the other two wires.

And I agree with you that most neutrals are grounded. I'm not arguing against that. 99.99973% of every neutral you see in the wild is grounded. My contention is that though most neutrals are grounded, grounding is not what qualifies it to be called neutral. It is a neutral if it fits the definition of I posted earlier. That was the 2020 code, but it is unchanged as far back as you want to go.
 
It is a common and it is a neutral. It is called "neutral" because it is in between the other two wires.

And I agree with you that most neutrals are grounded. I'm not arguing against that. 99.99973% of every neutral you see in the wild is grounded. My contention is that though most neutrals are grounded, grounding is not what qualifies it to be called neutral. It is a neutral if it fits the definition of I posted earlier. That was the 2020 code, but it is unchanged as far back as you want to go.
Funny enough a lot of folks also do not know what a ground is.
 
Grounding and bonding is the least understood concept in electrical practice. A huge part of the problem comes from using the word "ground" when the word "bond" is what is meant. The Canadians fixed this is their code, but the NEC still hangs on.
 
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