another electricution - metal street pole-baltimore!

[hurk27]

Re: another electricution - metal street pole-baltimore!

While I'll agree that it is allowed if the pole which the fixture is mounted is considered a separate structure. I feel it is a bad design and can cause problems if the neutral is lost.
Thank's for the responce's

 

[physis]

Re: another electricution - metal street pole-baltimore!

Why was the word neutral stricken from the NEC English language anyway? Wasn't it because of the 1/10 of a percent of the cases where there's no neutral or it has to be handled differently.

Neutrals still exist you know. I might be a complete novice to the NEC but I think pretending there's no such thing as a neutral is causing some confusion. Banishing the word neutral seems like the wrong answer to me.

 

[bphgravity]

Re: another electricution - metal street pole-baltimore!

The term "neutral" is in the NEC several times. There was going to be an actual definition in Article 100 added to the 2005 edition, however I believe it is was tabled for futher review and consideration. I feel it is likely to be in the 2008.

 

[apauling]

Re: another electricution - metal street pole-baltimore!

Charlie: you misunderstand my question. In the first paragraph that i was talking about, you talk about a system that is not connected to earth at all, not just not bonded. my question is...if the earth is not part of the loop of potential, how can there be a difference of potential. it's like a giant cap. needs to be connected at least at one end for a difference of potential to exist.

 

[physis]

Re: another electricution - metal street pole-baltimore!

it's like a giant cap

It is, and the ionosphere is the other plate. Capacitors store static charges. There are a good hand full of static sources.

Ok I wont say Tesla. But I'll say Shuman resonance.

 

[charlie]

Re: another electricution - metal street pole-baltimore!

Paul, please reread my last answer. You are correct in that their is no difference until something puts a potential on the floating system. That can be a higher voltage to ground (our primary system is grounded), lightning, or a static charge.

 

[apauling]

Re: another electricution - metal street pole-baltimore!

Charlie: reread post and answers, my mistake in assuming, in first mention of isolated, that you meant entire system when you said isolated system, not just an end user.

paul

 

[physis]

Re: another electricution - metal street pole-baltimore!

By Bryan:

There was going to be an actual definition in Article 100 added to the 2005

That's a weird thought. You'd have to define it. I can't even imagine what it would mean after being adapted for the NEC. Would we have "neutral conductors"? "Bonding conducters"

I already like it better, the earth could be ground again, stop calling the energized conductor an ungrounded conductor. Things could be grounded with a bonding (or grounding) conductor. And we could all go back to thinking of wires in relation to the system instead of to the ground.

 

[iwire]

Re: another electricution - metal street pole-baltimore!

It's not as easy to describe the conductors we use as I thought it would be.

Originally posted by physis:
stop calling the energized conductor an ungrounded conductor.

Energized conductor?

The grounded conductor and the grounding conductor are as 'energized' as the ungrounded conductor.

When I wire a transformer I could just as easily 'ground' phase A (X1) as I could ground the 'neutral' (X0)

 

[charlie]

Re: another electricution - metal street pole-baltimore!

Bob, that is interesting that you brought that up. I used to tell my apprentices the same thing, you may ground the secondary of two winding transformer or a 3? transformer one time and one time only anywhere and it will still work. It may not meet the requirements of the Code, but it will still work.

For instance, a 480Y/277V, 3?, 4w transformer could have one of its phases grounded and used in that manner. You would measure 480V between each phase and 277V to the neutral, no different than any other 480V system of the same configuration. However, from the grounded conductor to the neutral, you would measure 277V and also from the other two phase to ground would be 480V. </font>

• <font size="2" face="Verdana, Helvetica, sans-serif">Will it work? Yes</font>
• <font size="2" face="Verdana, Helvetica, sans-serif">Does it meet Code? No</font>
• <font size="2" face="Verdana, Helvetica, sans-serif">Is it safe? No, because you have set up a trap that would kill someone and equipment is not made for that configuration.</font>

<font size="2" face="Verdana, Helvetica, sans-serif">Then I went on to explain how a 480Y/277V, 3?, 4w transformer can have one of the phases grounded in the same manner and still meet Code by not bringing out the neutral conductor to be used as a neutral or grounding it (it must be ungrounded). Since only the three phase wires are available, it can be used as either a three wire delta or a grounded phase delta if you ground one of the phases.

 

[physis]

Re: another electricution - metal street pole-baltimore!

Supply conductor then, now don't tell me the neutral's gonna be jealous because it's a supply conductor too.

 

[iwire]

Re: another electricution - metal street pole-baltimore!

Originally posted by physis:
Supply conductor then, now don't tell me the neutrals gonna be jealous because it's a supply conductor too.

LOL over both the ungrounded and grounded conductors role of normally carrying current.

But yes the neutral is as much a supply conductor as the ungrounded conductor.

The only property that the ungrounded and the grounded do not have in common is a connection to earth.

[ January 01, 2005, 12:40 PM: Message edited by: iwire ]

 

[physis]

Re: another electricution - metal street pole-baltimore!

When I wire a transformer I could just as easily 'ground' phase A (X1) as I could ground the 'neutral' (X0)

 

[physis]

Re: another electricution - metal street pole-baltimore!

So you'd have a grounded supply conductor, and it shouln'd be called a neutral because it's not.

Isn't that the reason the NEC changed all the wire names to "anything that has the word ground in it". Because this concept is just too advanced for electricians.

So now if there is a grounded ungrounded conductor we pretend that there's nothing unusual here, everythings just like everything else, nobody needs to know, don't get yourself all confused.

Edit:

By Bob:

It's not as easy to describe the conductors we use as I thought it would be.

I'll certaily give you that. There is a need to be rather maticulous.

[ January 02, 2005, 05:58 PM: Message edited by: physis ]

 

[iwire]

Re: another electricution - metal street pole-baltimore!

Your confusing me Sam.

The white conductor in a 2 wire cable is never 'neutral', so why would we call it a neutral?

 

[iwire]

Re: another electricution - metal street pole-baltimore!

By the way all this grounding, grounded and ungrounded may change to bonding, bonded and unbonded in 2008.

Maybe Don or Charlie could fill us in a little more on where that is going.

 

[physis]

Re: another electricution - metal street pole-baltimore!

It is to neutral. If you don't know that, it doesn't change the system. In order to see the supply neutral as one conductor of a two wire system you first have to become miopic.

Is it not possible for an electrician to fathom the idea that if you only have two wires you might not be able use them as a multiwire cicuit?

 

[physis]

Re: another electricution - metal street pole-baltimore!

I'm hep to that and have mixed feelings. But I already been there on this thread. That's how we got here.

 

[iwire]

Re: another electricution - metal street pole-baltimore!

Originally posted by physis:
It is to neutral.

It is also 'to' the grounding electrodes, that does not make it a grounding electrode.

 

[physis]

Re: another electricution - metal street pole-baltimore!

It is also 'to' the grounding electrodes, that does not make it a grounding electrode.

It's funny you point that out because that's where the this and that ground ing or ed language is loosing the ability to convey a clear picture of the system. It's foggin it all up.

If you go back some pages, I got onto this because lot's of people in the trade just don't understand grounding. And it's too simple to not get.

Edit: I say the vending machine goes into table 3.2.1 Of the style manual

[ January 02, 2005, 06:29 PM: Message edited by: physis ]