uninsulated overhead grounded conductor

[iwire]

Re: uninsulated overhead grounded conductor

Originally posted by bgisborn:
However, you guys are dead wrong on the field use of the term "220 volt service".

Sorry Bob, your dead wrong. I know my background and that of almost all the others that have posted here to your thread.

I do not know anything about you, you have not told us what you do and I will stick with my first impression.

Your use and instance on '220 volts' tells me volumes about you experience with electrical systems.

In this area anyone that says 220 is not in the electrical trade.


As far as the safety issue you want to discuss, you have not provided any information that insulating the grounded conductor will add to safety.

All you have repeated is that with the large number of installations the probability exists for an accident. That is hardly a news flash. :roll:

 

[roger]

Re: uninsulated overhead grounded conductor

Bgisborn, your link list the same voltages (even less) that the tables in 430 (that I pointed you to in an earlier post) list, so what is your point?

As Iwire points out, the use of the term "220v" in this forum (forget outside of the forum) is a reason for the real question, and that is, what is it that you do, and why want you tell us? :roll:


Roger

 

[George Stolz]

Re: uninsulated overhead grounded conductor

In this area anyone that says 220 is not in the electrical trade. [[Big Grin]]

Well, back to flipping burgers I guess. Or maybe I'll tattoo it on my hand...
Talk about much ado about nothing!

 

[hurk27]

Re: uninsulated overhead grounded conductor

If anyone has experience with ordering motors for a job will know the importance of getting the voltages correct as it could cost big money if you order a 240 volt motor for a 208 job. I have yet to see a motor that is intended to be used in the USA to have a rating of 220v I have seen 230 volt and 200 volt but not 220 volt. Of course I have seen foreign equipment that had motors rated at 220 but also had a 50 Hz rating. You will notice that motors that have a 220 volt rating will have it at 50 Hz @ 60 Hz it will have a 230 volt rating just like a 200 volt rated motor @ 50 Hz will be 212 volts @ 60 Hz. Which will work on a 208 system. and while there are motors that will run from 240 to 208 it will only do so at a reduced HP.
I have seen VHO ballast that have a 220 volt rating in tanning beds that allow them to be buck or boost to control the UV output as the lamps get older but these also state 50Hz which would put them as intended for the European market just side stepped to our market to be used in these beds.

But the original question with the uninsulated neutral is unfounded as here in the US we have to bond most metal in a building to this neutral ( grounded conductor) in which having a insulated neutral would serve no purpose as every grounded item in a building would have to be insulated also. If a bare neutral is that much of a problem then why not require a break away connection in the service drop so all of the conductors would be unenergized? But even that would not be cost efficient to impose upon the utilities, which would end up costing us.

By the way: A lost neutral on a service will cause other problems that are much more dangerous that the unbalance neutral voltage. as in Ed's diagram the 180 volts on half of the building could cause a fire over heating lights, transformers Etc... and even this would not be prevented by having a insulated neutral.

 

[petersonra]

Re: uninsulated overhead grounded conductor

I don't get all that worked up about this kind of thing. I hear people say 110/115/120 or 220/230/240 for the common house voltages. i think we all know what is meant.

Its like when someone refers to 3 phase as 230/240 or 460/480. Although I can't recall ever hearing someone refer to a three phase 220V.

Interestingly, 208 always seems to come out 208V.

 

[Ed MacLaren]

Re: uninsulated overhead grounded conductor

Its like when someone refers to 3 phase as 230/240 or 460/480.

Sure, but I would be a little hesitant to pay much attention to someone who was still referring to a 480 volt system as "440 volts", which it was commonly called back in the 1940s. A 4-to-1 stepdown gave 110 volts.

On a forum like this, one of the few ways we have of judging whether an individual knows what they are talking about, is how they use the "technical jargon."

I'm thinking most of us form opinions, over time, about which contributors posts to read and which ones to skip.

Ed

[ December 16, 2004, 11:10 AM: Message edited by: Ed MacLaren ]

 

[rattus]

Re: uninsulated overhead grounded conductor

Ed, there are a number of us oldsters who remember 110, 115, 117, etc. and sometimes slip back in time. It is somewhat like the old timers speaking of "cycles" instead of "Herz". It says little about what they know. I know a brilliant Phd. who still says "cycles". In my case, I know the theory and a little of the practice but have never worked in the trade, so forgive me if I use the wrong buzz words now and then.

I find it very interesting and educational to read the posts of those who actually do the work and deal with the multitude of problems encountered in the real world.

 

[Ed MacLaren]

Re: uninsulated overhead grounded conductor

there are a number of us oldsters who remember 110, 115, 117, etc. and sometimes slip back in time

Yes, ain't that the truth!

Ed

 

[charlie]

Re: uninsulated overhead grounded conductor

I wonder how old you have to be to be considered an oldster?

 

[bgisborn]

Re: uninsulated overhead grounded conductor

Charles, if you're much under 70 your not an oldtimer.
Basically, it's this way. Us oldtimers were pulling wires when you kids were wetting diapers. We have seen a lot of changes over the years and many changes in terminology. I, as many oldtimers, use terminology that is dated and not literally accurate. Sure, I still call it 440 when it is 480 or refer to hot legs and a neutral. I've worked all over the United States, in the Middle East and Europe and I never have had trouble being understood. I admit to having an occassional "senior moment", but I usually am able to recall my lapse and correct myself.
I've got some advice for you kids-and that includes those of you in your fifties: Stop playing Mike Holt. I met Mike, and I can tell you he's a great guy, highly knowledgeable, and a great teacher-but I thank the Good Lord there is only one of him.

Bob

 

[charlie]

Re: uninsulated overhead grounded conductor

Bob, I am past my 50's and into the 60's but I would rather be in my 40's.

 

[peter d]

Re: uninsulated overhead grounded conductor

Originally posted by bgisborn:
Basically, it's this way. Us oldtimers were pulling wires when you kids were wetting diapers.

And your point is? I'm pretty young myself, (under 30), and right now, as I'm pulling wire, future electricians are in their diapers too. Nothing's changed there. :roll:


"110/220" are laymans terms and will remain that way, whether you like it or not.

 

[bgisborn]

Re: uninsulated overhead grounded conductor

Peter you are as wrong as a person can be and I can give you all the evidence you want. 220 was a common voltage in the United States when I began work in the early fifties. 220/440 volt 60 cycle motors were as common as mud. 220 feeders were as comon as mud. Evidence? Here's a link to a used motor supply house and a 220/440 slip ring motor. Believe me I don't expect you to know what a trolly car starter or a slip ring motor is, but you can read the tag. 220/440 volt 60-not 50- cycle for the US market. Now, just as we had 440/220 motors and transformers we had 220 volt panels. 110 was a common residential voltage and was refered to as simply that-110. the voltage was understood.
Oh, the link.
http://www.surplusrecord.com/cgi-bin/adpop.pl?23979
If I gave you links to a thousand 220 volt motors would that convince you?
I'm just wondering if any of you guys know what a trolly car starter is or how to start a motor with one or why that's important with a crowned pully. Not that you should or need to know.
I make errors, but when I'm shown hard evidence, I correct the error. I've given you documented evidence on what we have been discussing and the have received personal insult from a few of you. I sorry this whole discussion has had to break away from safety and the subject I was discussing about a possibly unsafe practice. You are apparently a younger group and I may be a little behind the curve.

Bob

 

[bgisborn]

Re: uninsulated overhead grounded conductor

Peter, I made an error. I wish to apologize. I did not mean you were wrong just that 110/220 or 220/110 quote you had in your post. Sorry about that. It was what was implied in that quote that really ticked me off. Because older electricians did so much work with 220 many of us began applying it to all services in that range while understanding that is was only a nominal representation. We did the same with 440 when 480 became common.


Bob

 

[charlie]

Re: uninsulated overhead grounded conductor

I have made the assumption that everyone knew this but my assumption may not be correct. The correct voltage at one time was 110, then it changed to 115, and it is now 120. I don't know when those changes were made but all of the other voltages changed with it.

 

[peter d]

Re: uninsulated overhead grounded conductor

bgisborn,

No need to apologize. I think the issue here is "What are you used to?" I don't doubt that at one time 110 and 220 may have been standard voltages, but they are no longer.

All myself and the others have tried to point out is how once standardized terms have now become terms used by non-electricians and DIYers.

[ December 16, 2004, 10:04 PM: Message edited by: peter d ]

 

[rattus]

Re: uninsulated overhead grounded conductor

May I say that this exchange about the jargon is more ado about something trivial and has nothing to do with the topic.

 

[charlie]

Re: uninsulated overhead grounded conductor

Rattus, I think the original question has been answered. The rest of this is just conversation. It all boils down to a couple of things.</font>

• <font size="2" face="Verdana, Helvetica, sans-serif">Service drops are reasonably safe the way they are</font>
• <font size="2" face="Verdana, Helvetica, sans-serif">Using 220 or 110 instead of 240 and 120 is not much different than saying don't instead of doesn't when it is needed. It kind of identifies you as unknowledgeable whether you are or not.</font>

<font size="2" face="Verdana, Helvetica, sans-serif">I know that the service drop neutrals are not going to be insulated and I know people the use poor code language. The service drop neutrals are fine and so is the language.

 

[bgisborn]

Re: uninsulated overhead grounded conductor

Please, let me give a bit of information that may help you. The electrical service voltages in the United States vary from 220 to 240. Nominal 230 volts with the exception of New York and other areas where 208 volts is still used. Most appliances used in the United States designed for resisential service are designed for 230 volts. This allows them to work well on 220 to 240 with some loss on 208 (I would not for a heavy inductive load). This is the reason you'll see small single phase motors with a 230 volt tag.
My mention of 220 volts in my scenario was an inadvertant reference that had nothing material to do with my thesis. I corrected this reference in the next post. The use of a 220 volt designation comes from an old habit developed when 220 volts was widely used. This nominal desigation is as accurate for this example as the nominal 230 volt used by the industry. I did make a mistake in typing wye wye for the source of 240-which someone caught. Everything else I said was factually correct.
I think I can safely assume most of you have little experience with 220 volt feeders, which got an impulse to be replaced by 240 during the big run up of copper prices in the 60's. That is also when aluminum wire- oh, excuse me-conductor, became popular.
Now, once more and for the last time: A single overhead service with an uninsulated conductor is safe with little chance of causing an electrocution, but this tiny chance becomes far more probable when there are millions of installations.
In regards to safety practices, in general, a statistical study is made over many cases. An extension cord is safe. We use them every day. But there are small inherent dangers with their use that become considerable when taken over a large number and variety of uses.
Someone mentioned the greater danger of breaking just the neutral. That's something every electrician knows-or better know. My scenario did not say only the neutral was broken-it excluded this. Those of you who insulted me did so on the basis of what you understood to be correct jargon in your little corner of the world and your short experience in the industry.

Bob

 

[Ed MacLaren]

Re: uninsulated overhead grounded conductor

I've been told that, even for a retired instructor, I have an unnatural obsession with accuracy.

Ed

[ December 17, 2004, 11:52 AM: Message edited by: Ed MacLaren ]