Motor run in reverse?

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Re: Motor run in reverse?

Someone care to break down the above post and explain it to me...beacuse I'm lost. :D
 
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.
 
Re: Motor run in reverse?

neutral.JPG
 
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.
 
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!
 
Re: Motor run in reverse?

That's not a limb you're on Crossman, you've only stated the obvious. :p

I'm currently very interested in this topic. Can you find a more challenging example?
 
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?
 
Re: Motor run in reverse?

Looks like a neutral to me, but...maybe I Just am still lacking the understanding to know why that's not a neutral. What's a tap? I'm not too fimiliar with that word yet.
 
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 ]
 
Re: Motor run in reverse?

Originally posted by crossman:
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!
Click to expand...
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
Grounded Conductor. A system or circuit conductor that is intentionally grounded.
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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.
 
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. :D

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. :cool:
 
Re: Motor run in reverse?

Originally posted by physis:
This stuff is pretty fundimental to all of us and therefore also stirs up controversy.
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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. :D Just kidding, I think they just are having a hard time coming up with a rock solid definition.

Roger or Don could elaborate on this.

Now get in bed so you are well rested for work. ;)
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Re: Motor run in reverse?

And it's the equipment grounding conductor that Don wants changed to equipment bonding conductor. Which I fully support if I can have the omission of the word equipment.
 
Re: Motor run in reverse?

Yeah yeah, I'm trying to.

It really is amazing how much thought something that seems so simple takes. A lot of ways of looking at it.

Good night Bob, I'll argue with you more tommorow. :)
 
Re: Motor run in reverse?

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
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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- :cool:

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
 
Re: Motor run in reverse?

Sam,
The word "equipment" in equipment bonding jumper is required because there are other types of bonding jumpers.
Don
 
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?

notneutral.jpg
 
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 ]
 
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. :D
 
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