Motor run in reverse?
- Thread starter midget
- Start date
- Status
crossman
Senior Member
- Location
- Southeast Texas
Re: Motor run in reverse?
Okay, I'll take a shot!
Someone up there said something about "you should never connect a neutral to a motor".
I disagree. There are 120 volt motors connected to neutrals all over the place.
Then someone said something about "neutral" carries unbalanced current, otherwise it is only a grounded conductor. I can agree with that.
I was going to go to bed, but let me draw a picture... give me ten minutes. I'll be back.
Okay, I'll take a shot!
Someone up there said something about "you should never connect a neutral to a motor".
I disagree. There are 120 volt motors connected to neutrals all over the place.
Then someone said something about "neutral" carries unbalanced current, otherwise it is only a grounded conductor. I can agree with that.
I was going to go to bed, but let me draw a picture... give me ten minutes. I'll be back.
crossman
Senior Member
- Location
- Southeast Texas
Re: Motor run in reverse?
physis
Senior Member
Re: Motor run in reverse?
It is exactly that. Symantic.
When there are only two wires present they, by themselves, behave exactly as if there is no neutral in the circuit.
On the other hand, if one of them is, in actuality, a neutral, if for any reason additional outside factors become introduced into the circuit then the fact that one of the conductors is a neutral will again have meaning.
Personally, the way I'm used to dealing with it is that the nature of the source is never ignored.
It is exactly that. Symantic.
When there are only two wires present they, by themselves, behave exactly as if there is no neutral in the circuit.
On the other hand, if one of them is, in actuality, a neutral, if for any reason additional outside factors become introduced into the circuit then the fact that one of the conductors is a neutral will again have meaning.
Personally, the way I'm used to dealing with it is that the nature of the source is never ignored.
crossman
Senior Member
- Location
- Southeast Texas
Re: Motor run in reverse?
I'm going to go out on a limb and say that the above motor IS INDEED connected to the neutral of a multi-wire branch circuit and it is perfectly safe and legal.
All semantics aside!
I'm going to go out on a limb and say that the above motor IS INDEED connected to the neutral of a multi-wire branch circuit and it is perfectly safe and legal.
All semantics aside!
crossman
Senior Member
- Location
- Southeast Texas
Re: Motor run in reverse?
Thorry!
I was just interested in that "never connect a neutral to a motor" statement from up above. And I did not see a satisfactory answer so I brought it up again.
I'm happy now.
So what else would interest you about the subject?
Thorry!
I was just interested in that "never connect a neutral to a motor" statement from up above. And I did not see a satisfactory answer so I brought it up again.
I'm happy now.
So what else would interest you about the subject?
physis
Senior Member
Re: Motor run in reverse?
Crossman,
I'm just not happy with NEC conductor names all of a sudden and I'm sort of gathering perspectives on the issue.
It's mostly interesting where there's disagreement because that's where the language problems are.
It's not electrical theory, that works fine.
[ January 04, 2005, 03:20 AM: Message edited by: physis ]
Crossman,
I'm just not happy with NEC conductor names all of a sudden and I'm sort of gathering perspectives on the issue.
It's mostly interesting where there's disagreement because that's where the language problems are.
It's not electrical theory, that works fine.
[ January 04, 2005, 03:20 AM: Message edited by: physis ]
- Location
- Massachusetts
Re: Motor run in reverse?
I disagree with it being called a neutral in your drawing. A neutral caries only the imbalance between two or more ungrounded conductors.
In a two wire circuit there is no neutral, it is the grounded conductor.
Article 100
Would we call that wire at the motor a grounding conductor? It is connected to the grounding conductors.
In causal conversation I would call it a neutral, in technical discussions like we have here on this board I call it the grounded conductor. At least until the NEC changes to bonded.
Sorry Sam.
Of course it is safe and legal and yes eventually it is connected to a neutral
I disagree with it being called a neutral in your drawing. A neutral caries only the imbalance between two or more ungrounded conductors.
In a two wire circuit there is no neutral, it is the grounded conductor.
Article 100
You call it a neutral because it connects to the neutral bus. Well that neutral bus also connects to the grounding conductors and grounding electrodes.
Would we call that wire at the motor a grounding conductor? It is connected to the grounding conductors.
In causal conversation I would call it a neutral, in technical discussions like we have here on this board I call it the grounded conductor. At least until the NEC changes to bonded.
Sorry Sam.
physis
Senior Member
Re: Motor run in reverse?
Bob, I was going to bed. Now I have to convince you that only one of us can be right and I think it should be me.
Actually I've decided that debating when and where and why you should or shouldn't call a neutral a neutral isn't really necessary at least as far as NEC conductor terminology.
It hasn't taken me long to see that there are some significant and also well founded fellings related to the use of the term "neutral".
This stuff is pretty fundimental to all of us and therefore also stirs up controversy.
Any wonder the CMP's would rather leave it out. I now agree.
Bob, I was going to bed. Now I have to convince you that only one of us can be right and I think it should be me.
Actually I've decided that debating when and where and why you should or shouldn't call a neutral a neutral isn't really necessary at least as far as NEC conductor terminology.
It hasn't taken me long to see that there are some significant and also well founded fellings related to the use of the term "neutral".
This stuff is pretty fundimental to all of us and therefore also stirs up controversy.
Any wonder the CMP's would rather leave it out. I now agree.
- Location
- Massachusetts
Re: Motor run in reverse?
After thinking on it it became clear in my mind it was only a grounded conductor.
Very true, I agree entirely, the first time this issue was brought to my attention I said "What the ^%# of course it is a neutral"
After thinking on it it became clear in my mind it was only a grounded conductor.
Originally posted by physis:
Any wonder the CMP's would rather leave it out. I now agree.
Roger or Don could elaborate on this.
Now get in bed so you are well rested for work.
Ed MacLaren
Senior Member
Re: Motor run in reverse?
How would one person know which wire the other was talking about?
Now that the subject of the definition of a neutral conductor has come up-
The adjective "Neutral" is most commonly used to denote some "thing" that is "between" at least two others, and "favoring" neither, such as a country that does not support any of the combatants in a war.
Some other examples ?
1. Someone that does not side with either party in a controversy.
2. The center ice zone in a hockey arena.
3. Not in any gear in a manual auto transmission.
A neutral conductor -
"A conductor (when one exists) of a polyphase circuit, or a single phase 3-wire circuit, which is intended to have a voltage such that the voltage differences between it and two or more ungrounded conductors are approximately equal in magnitude and equally spaced in phase."
Ed
Exactly! It is impossible to have a productive discussion in a forum like this if the participants are using different "languages".
How would one person know which wire the other was talking about?
Now that the subject of the definition of a neutral conductor has come up-
The adjective "Neutral" is most commonly used to denote some "thing" that is "between" at least two others, and "favoring" neither, such as a country that does not support any of the combatants in a war.
Some other examples ?
1. Someone that does not side with either party in a controversy.
2. The center ice zone in a hockey arena.
3. Not in any gear in a manual auto transmission.
A neutral conductor -
"A conductor (when one exists) of a polyphase circuit, or a single phase 3-wire circuit, which is intended to have a voltage such that the voltage differences between it and two or more ungrounded conductors are approximately equal in magnitude and equally spaced in phase."
Ed
- Location
- Illinois
- Occupation
- retired electrician
Re: Motor run in reverse?
Sam,
The word "equipment" in equipment bonding jumper is required because there are other types of bonding jumpers.
Don
Sam,
The word "equipment" in equipment bonding jumper is required because there are other types of bonding jumpers.
Don
crossman
Senior Member
- Location
- Southeast Texas
Re: Motor run in reverse?
This is getting amusing!
Okay, my last post on the subject, but just to make sure we are on the same page:
Is this what we are talking about? If so, I can agree with this.
And we can pretty much say that the light bulb in the drawing is not connected to the neutral either. In fact, no utilization equipment is ever connected to the neutral, not just motors?
This is getting amusing!
Okay, my last post on the subject, but just to make sure we are on the same page:
Is this what we are talking about? If so, I can agree with this.
And we can pretty much say that the light bulb in the drawing is not connected to the neutral either. In fact, no utilization equipment is ever connected to the neutral, not just motors?
Ed MacLaren
Senior Member
Re: Motor run in reverse?
When I made my statement on Page 1 - "You should never see a neutral wire connected to a motor." - I was thinking in terms of a real motor.
You know, on it's own branch circuit, with a disconnecting means, and starter, etc. Code legal.
Of course, it is possible in theory to connect a motor with a light to a multi-wire circuit as Crossman has depicted above, and it is indeed connected to the neutral.
But, out in the real world - - - -
Ed
[ January 04, 2005, 10:41 AM: Message edited by: Ed MacLaren ]
When I made my statement on Page 1 - "You should never see a neutral wire connected to a motor." - I was thinking in terms of a real motor.
You know, on it's own branch circuit, with a disconnecting means, and starter, etc. Code legal.
Of course, it is possible in theory to connect a motor with a light to a multi-wire circuit as Crossman has depicted above, and it is indeed connected to the neutral.
But, out in the real world - - - -
Ed
[ January 04, 2005, 10:41 AM: Message edited by: Ed MacLaren ]
- Location
- Massachusetts
Re: Motor run in reverse?
A truly Canadian example.
peter d
Senior Member
- Location
- New England
Re: Motor run in reverse?
Crossarm, (or any other drawing savvy person )
Could you tell us how you are making your drawings? It looks like Word to me, but I could be wrong.
Crossarm, (or any other drawing savvy person
)Could you tell us how you are making your drawings? It looks like Word to me, but I could be wrong.
- Status